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RULES OF PLAY

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Table of Contents 1.0 Introduction ��3

[7.12] DECK GUN/AIRCRAFT REMOVAL AND KAITEN ��15

2.0 How to Play the Game ��3 OBJECT OF THE GAME ��3

[7.13] SPECIAL MISSION COMPLETION ��15

CONDUCTING PATROLS ��4

[7.15] AIRCRAFT LAUNCH AND RECOVERY ��15

3.0 Game Equipment ��5

[7.17] THE AIRCRAFT MODULE ��16

GENERAL OVERVIEW ��4

[7.14] MAJOR EVENT MARKERS ��15

END GAME ��5

[7.16] THE MIDGET SUBMARINE MODULE ��15 [7.18] THE KAITEN MODULE ��17

[3.1] SUBMARINE DISPLAY MAT ��5 [3.2] ATTACK MAT ��5

8.0 Combat �� 17

[3.4] CHARTS AND TABLES ��6

[8.2] ENCOUNTERS WITH SHIPS: ATTACKS AGAINST SHIPPING ��18

[8.1] GENERAL PROCEDURES ��17

[3.3] THE PLAYING PIECES ��5 [3.5] THE PATROL LOG SHEET ��6

[8.3] AIRCRAFT ENCOUNTERS ��21

[3.6] GAME SCALE ��7

[8.4] “FOLLOWING” A CONVOY OR SHIP ��22

[3.7] PARTS INVENTORY ��7

[8.5] SUBMARINE DAMAGE ��22

4.0 Game Set-Up ��7

[8.6] PATROL ABORT ��24

GENERAL RULE ��7

[8.7] CREW SKILLS AND ADVANCEMENT ��25

[4.1] SUBMARINE MODEL SELECTION ��7

[8.9] PROMOTIONS ��26

[4.2] START DATE ��7

9.0 Reassignment to a Newer Boat ��27

[4.3] PREPARE PATROL LOG SHEET ��8

[9.1] REASSIGNMENT DUE TO HOSPITAL STAY ��27

[4.4] SUBMARINE DISPLAY MAT SETUP ��8

[9.2] REASSIGNMENT DUE TO REFIT ��27

PROCEDURE ��9

[9.3] UPGRADE DUE TO UPGRADE MARKERS ��27

[4.6] AMMO MARKERS ��9

10.0 Multi-Player/Tournament Rules ��27

[4.7] BASING ��10

[10.1] TWO PLAYER GAME

[4.8] TRAINING SCHOOLS ��10

��27

[10.2] TOP TONNAGE TOURNAMENTS ��27

5.0 How to Win the Game ��10

[10.3] SURVIVAL TOURNAMENTS ��27

[5.1] ENDING THE GAME ��11

[10.4] MIXED BOAT TOURNAMENTS ��27

[5.2] DETERMINING VICTORY ��11

11.0 Optional Rules ��27

6.0 Sequence of Play ��11

[11.1] STANDARD TONNAGE AMOUNTS ��27

GENERAL RULE ��11

[11.2] INCREASED HISTORICAL TARGETING ��27

GAME PLAY OUTLINE ��11

[11.3] EVASIVE MANEUVERS ��28

7.0 Special Missions and Major Events �� 13

[11.4] VARIABLE ESCORT QUALITY ��28

[7.1] RECONNAISSANCE ��13

[11.5] VARIABLE AIRCRAFT QUALITY ��28

[7.2] PICKET LINE ��13

[11.6] HISTORICAL SUBMARINE I.D. ��28

[7.3] MIDGET SUBMARINE ATTACK ��13

[11.7] OPTIONAL SPECIAL ABILITIES ��29

[7.4] TRANSPORT ��13

[11.8] OPTIONAL NAME GENERATOR ��30

[7.5] STRATEGIC TRANSPORT (EUROPE) ��14

12.0 Example of Play �� 30

[7.6] EVACUATION ��14

Designer’s Notes �� 31

[7.7] BOMBING MISSION ��14 [7.8] KAITEN ATTACK ��14

Selected Bibliography �� 31

[7.10] MINE-LAYING ��14

RULES INDEX ��32

Credits: �� 31

[7.9] SHORE BOMBARDMENT ��14 [7.11] PASSENGER DELIVERY ��15

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1.0 Introduction

IF YOU ARE NEW TO OR UNFAMILIAR WITH HISTORICAL GAMES, DON’T PANIC! First look at any of the Submarine Display Mats, the Submarine Attack Mat, and the playing pieces, then give the rules a quick read through. Please don’t try to memorize them. Follow the setup instructions for play and then read Section 2.0 that describes the general course of play. Section 4.0 provides the framework to help you get started. As questions arise simply refer back to the rules. After a few minutes of play, you will find yourself becoming familiar with the game mechanics. You need to also realize most of the charts in the game are not even used in some games, or referred to only once. Don’t feel overwhelmed by all the charts, as very few will be utilized depending on which submarine you have chosen.

Japan started World War II with 64 submarines; of these, 21 were older, obsolete types that would be of little use other than training. Still, with over 40 firstline submarines, they posed a significant threat to the American Navy. Japanese doctrinal use of their submarines, however, never allowed them to fulfill their true potential. Forced into picket line duties, reconnaissance, and in launching aircraft to bomb mainland America to little effect, the effort mainly dwarfed the meager results. It is interesting to think of what their submarine force could have achieved had it been wielded more like the Americans submarine force. Japanese prewar doctrine was that the submarine’s main purpose was to conduct surprise attacks on the enemy’s main force, to act as an advance force while again, attacking the enemy’s main force and providing reconnaissance. There was never a real mention of using submarines for what they do best – interdicting an enemy’s lines of communications and logistics by destroying shipping.

Online game support is available. There are several options to choose from: Visit us on the Web: compassgames.com (Compass Games Home page)

Sensuikan: Japanese Fleet Submarines, 1941-45 is a solitaire, tactical level game placing you in command of a Japanese fleet submarine during WWII. Your mission is to destroy as much Allied shipping and as many capital ships as possible, but primarily you will be conducting special missions as assigned by the Combined Fleet. You will be advancing your crew quality and increasing your commander’s rank and awards—all while remembering you have to make it home amidst diminishing odds of survival as the war progresses.

Players will find it challenging to survive an entire tour from 1941 to 1945, at which time, if still alive, you will surrender at port, having done your part on the front lines. If desired, a player may start with a more advanced model of submarine, which may actually increase the chance to survive but give you less time to obtain a better score. You may start at any month/year you wish, but notice that while some submarines are available right away, others are not available until later. Players may be reassigned to a newer model of submarine under some circumstances, but typically will stay in the same boat until the end of game or until sunk. The rules are numbered and presented in sets of major sections, each section divided into numerous major and secondary cases. The rules cross-reference other rules using (parentheses), so for example you will see, “The total number of torpedoes loaded will always equal the boat’s capacity. Exception: (7.10) Mine-laying Special Mission.” meaning Case 7.10 is related to this rule. The rules of this game have been arranged both for ease of comprehension on first reading and for ease of reference later.

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General customer service and game parts support are provided by Compass Games (see rule 3.7). Throughout the rules you will see numerous indented sections such as this one. These sections are filled with examples, clarifications, play hints, design notes and other assorted wisdom in order to help ease you along.

2.0 How to Play the Game OBJECT OF THE GAME

The object of the game is to conduct numerous patrols as a Japanese submarine commander, conduct special missions, and sink enemy ships. The success of each patrol is reflected by the total tonnage of ships sunk or any special mission completed, which can result in promotion and crew advancement—culminating in receiving the highly coveted award of the Order of the Golden Kite. Your submarine and crew will face relentless risks as each patrol becomes more hazardous due to the increased Allied ASW

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fire. While unescorted ships are relatively easy targets, if you do not sink them quickly, you run the risk of escorts appearing on the scene when attempting additional rounds of combat to finish them off.

effectiveness as time passes. The ultimate success you achieve rests considerably on the decisions you make while conducting patrols during the course of your career. Overall victory level is determined at the end of the game based on total tonnage sunk modified by successful special missions (which can also be determined posthumously if you as Captain are killed in action).

Combat engagements against escorted ships, typically when engaging a convoy, are fraught with risks—especially should you decide to engage at close range (in which case the escorts can attempt detection before you can fire any torpedo salvo). The escorts will have an opportunity to detect your Submarine, and once detected, your Submarine may come under repeated depth charge attacks until you are able to escape further detection. You may even attempt to exceed test depth to try and shake free of the escorts. Damage results, including crew injury, put you at greater risk while under attack and trying to escape escort detection.

The key game components used to facilitate play are the Submarine Display Mat to track the status of your submarine and crew along with tracks for each patrol assignment, the Attack Mat to resolve ship encounters, and the Patrol Log Sheet to track the activity and success of each patrol. The various Player Aid Cards are used to resolve game functions.

GENERAL OVERVIEW

Once you escape escort detection, you will attempt to repair any damaged systems, with failed repairs resulting in inoperable systems, which could potentially cause you to abort the patrol. Once an engagement ends against escorted ships, you have the option to automatically follow any damaged ships, or attempt to reengage the entire convoy.

In general, play revolves around conducting numerous patrol assignments and resolving any encounters at sea until safely returning to port. Upon completion of each patrol, you assess the success achieved by consulting your log sheet, which may result in a promotion/award for yourself as Captain or possible crew advancement. Between patrol assignments, your submarine will be refitted for one or more months based upon damage incurred. You may also need time to recuperate from any personal injury before being able to conduct your next patrol.

If given a special mission, players will, at the travel box where the mission is to be conducted, possibly consult one of the three game modules of play. These modules may be considered temporary “subroutines” to the game (no pun intended) where special rules apply for dealing with midget subs, on-board aircraft launch and recovery, and kaiten “suicide torpedo” operations. Some special missions simply use normal game routines, such as “Picket Line” duty.

CONDUCTING PATROLS Your Submarine Display Mat shows the overall status of your submarine and crew, including armaments. When conducting patrols, your submarine progresses through the Travel Boxes on the Patrol Track, checking for possible encounters in each Travel Box entered, including the possibility of a random event.

Enemy aircraft encounters put your submarine at immediate risk, as you attempt to crash dive to avoid imminent attack. Should an air attack be successful, you will engage your AA gun(s) in the hope you can damage or take down the enemy aircraft. If you fail to damage or destroy the aircraft, you run the risk of undergoing additional air attacks, or even having escorts arrive on the scene to hunt you down.

Typically encounters involve ship encounters or aircraft encounters. Ship encounters specify whether the enemy ships are under escort, which plays a significant role when engaging them, as your submarine may be detected and come under repeated depth charge attack. For each ship encounter you decide to engage in combat, you will make decisions to determine time of day, whether you will conduct surface or submerged combat, and at what range you will engage the target ships and fire your torpedoes. You will also record all ships you engage during combat on the log sheet, noting whether you damaged or sunk them. When conducting surface engagements against unescorted ships, you can also employ your deck guns if so equipped.

SUBMARINE REFIT

As you conduct combat, you will roll for the amount of damage incurred against targeted ships with your torpedoes (as long as they were not duds) and/or deck gun

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Once your submarine completes its patrol assignment by returning to base (after any possible encounter in the last Travel Box on the Patrol Track), it undergoes a refit. The length of refit depends on the class of the submarine and the amount of hull damage and inoperable systems requiring repair. Furthermore, convalescence for the submarine Captain (you) can result in delays. The possibility exists that you may be assigned a newer submarine or lose some of your crew (as they need more time to recover from their injuries). During refit, you are

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also able to evaluate the relative success of your patrol, which can result in crew advancement or promotion, including various awards. Following refit, before your submarine begins its next patrol assignment, all systems will be operational and you will be fully stocked with armaments and a full crew. Your submarine might also be bombed during refit starting in January 1944.

[3.2] ATTACK MAT The Attack Mat [H1] is used to resolve combat against shipping targets and is typically set beside your Submarine Display Mat during play. The use of this mat is explained in the appropriate rules section.

END GAME Once all patrol assignments have been carried out through July 1945, the game ends. Also, should you as Captain be killed in action or be captured, or should your submarine be sunk, scuttled, or captured, the game immediately ends. Whether you survive until your final patrol or not (ending after July 1945), tally the total tonnage of ships sunk to determine your level of victory achieved and adjust it by special missions successfully performed. Typically, to record an entire career, you will want to note all ships sunk (including any capital ships), your final rank, and any awards achieved. Of course, if you have gone down with your ship, any accolades and results are recognized posthumously.

[3.3] THE PLAYING PIECES

3.0 Game Equipment

The Sensuikan playing pieces come on two die-cut sheets. These playing pieces are referred to as markers (or counters) and are placed on either the Submarine Display Mat to track status of your submarine and crew, or the Attack Mat when resolving combat. Markers are provided for individual ships, aircraft, crew members, individual torpedoes, ammo rounds, random events, and the status of crew and systems.

[3.1] SUBMARINE DISPLAY MAT The 9 Submarine Display Mats (doubled-sided, for 18 total mats) provided correspond to each Japanese submarine class available to players, along with Patrol Tracks containing individual Travel Boxes to track the progress of your patrol. This mat helps track the status of your crew and systems, including available armaments at your disposal. Select the appropriate Display Mat corresponding to the submarine type you have selected for play. This mat is the centerpiece when conducting game play and carrying out patrol assignments. The use of this mat is explained in the appropriate rules section.

Note: extra markers— (additional torpedo markers, for example)—have been printed as spare parts should any become missing or damaged.

[3.3.1] HOW TO READ THE MARKERS The Sensuikan counter mix provides markers to track the status of your submarine and for resolving engagements. These markers may include information, such as die-roll modifiers, to facilitate play. An explanation of each marker type is explained below.

[3.3.2] GAME MARKERS Submarine: The submarine marker corresponds to the type you have selected and is placed on the Submarine Mat to track progress of your assigned patrol. Each of the 17 submarine markers lists its corresponding type.

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Officer Rank:

Crew Status:

Three numbered Officer Rank markers are provided (from 1, the lowest, to 3, the highest) to track your promotion level as submarine Captain.

Crew status markers are provided to track severity of injury or KIA results. Specialized crew members can also rise to “Expert” level (11.1) which provides certain benefits during play.

Medal & Rewards:

Attack Mat Markers:

Various medals, awards, and badges may be bestowed on you based on your career success.

Markers are provided for the Submarine Attack Mat [H1] when resolving encounters. These markers include Day/Night, range of engagement, type of ships targeted, and markers for Escort and Aircraft Quality. Please note that Torpedo and Ammo markers will be expended and moved from your Submarine Display to the Attack Mat when resolving combat.

Crew Quality: The crew quality corresponds to the experience and performance of your crew. Your crew begins at “Trained” level. It may rise to “Veteran” then “Elite” or may drop to “Green” Random Event:

Note on Terminology: “drm” stands for “die roll modifier” or “dice roll modifier” and is used throughout the game rules and charts to indicate an integer which modifies the result of a die or dice roll upwards or downwards. Anytime a result is modified to go above or below the listed results due to a drm, it should be considered to be the maximum or minimum result possible, respectively.

While most Random Events are resolved immediately, some can be used later during play and these markers should be placed on the Submarine Display Mat until used. Skills:

[3.4] CHARTS AND TABLES

Skill markers increase the player’s chances of survival and success, and are earned from submarine school or by the player’s choice every third successful mission.

Thirteen two-sided and one single-sided Player Aid Cards are provided to facilitate game play and resolve game functions. The use of these charts and displays are explained in the appropriate rules section. Specific charts and tables are referenced by their ID in [square brackets].

Armaments: Torpedo markers represent individual torpedoes by type. These are: Type 89 (Steam,) 6th Year Type (Steam,) Type 95 (Oxygen) or Type 92 (Electric). Midget Submarines use a smaller 18” torpedo, the Type 97. Ammo markers track the number of rounds available for each Deck Gun.

When a die roll is called for, each table specifies the die roll combination necessary, which in some cases may include each die representing a different place value. In such instances, use a colored die to distinguish place values. For example, for a roll of “1d10+1d10,” the first d10 represents the tens’ place value and the second d10 the ones’ place value. Treat a result of “00” as “100,” not “0.”

Additional markers include Supplies, Midget Submarines, Kaiten, Aircraft, and a host of other objects.

[3.5] THE PATROL LOG SHEET

Additional markers:

The Patrol Log Sheet is used to record for each game session your submarine type, ID, and Captain’s name, along with individual patrol assignments, damaged or sunk ships, and length of refit following each patrol. Feel free to photocopy these sheets as needed.

Damage:

Markers are provided to track Hull Damage, Flooding Level, and any possible damage to Engines and other systems. These markers are only placed on your Submarine Display Mat when damage occurs. Note: both named markers for specific systems are provided, as well as generic markers. We recommend you use the named damage markers to better track what system(s) are Damaged or Inoperable (which is helpful should your Display Mat accidentally be disturbed with markers becoming displaced).

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[3.6] GAME SCALE

[4.1] SUBMARINE MODEL SELECTION

Each Travel Box on the Submarine Display Mat represents roughly four to six days on patrol. Generic crew boxes represent several crewmen of the approximately 70-100 on-board. Select markers represent individual ships, aircraft, specific crew members, individual torpedoes, and ammo rounds.

Begin by selecting one of the seventeen submarine types that you wish to captain and place the corresponding Display Mat in front of you. Only one submarine type should be selected. See 4.2, Start Date, to see what submarine types are available at different dates. Earlier start dates allow for more patrols, but later start dates have more advanced submarines available. Game play consists of being the captain of a single submarine rather than simulating control of multiple submarines on patrol.

[3.7] PARTS INVENTORY

Note: you can start with a more advanced submarine model, such as the Type A (Modified) but it does not become available until May 1945, which means you will not have the early months of the war to rack up a larger score.

A complete game of Sensuikan includes the following components: •

Two full-color counter sheets

•

13 Player Aid Cards, 2-sided

• • • • • • • • •

[4.2] START DATE

One Rules Booklet with Designer’s Notes

[4.2.1] Your first patrol will be in December 1941 unless you choose a Type not available until later in the war.

One Player Aid Card, single sided

[4.2.2] Available dates are given for the entire war and are listed in chronological order for each submarine type:

One Patrol Log Sheet pad

Nine Submarine Display Mats (17 submarine classes and one Midget Submarine), 2-sided

Submarine Types Type Kaidai KD. 3 Kaidai KD. 4 Kaidai KD. 5 Kaidai KD. 6 Kaidai KD. 7 Junsen J. 1M Junsen J. 2 Junsen J. 3 Kirai-Sen Type A Type B Type C Type C. 3 Type B. 3 Sen-Toku Sen-Taka Type A (Mod)

One Operations map One Attack Mat

Two 6-sided, one 20-sided, and two 10-sided dice One Game box with lid

One set of Sequence of Play cards (7 cards total)

If any of these parts are missing or damaged, please contact our publisher: Compass Games, P.O. Box 271, Cromwell, CT, 06416 E-Mail: support@compassgames.com

4.0 Game Set-Up GENERAL RULE Game setup consists of selecting your submarine type, preparing your log sheet, and placing the corresponding Display Mat in front of you for initial marker placement prior to conducting your first patrol. You should also have the Attack Mat [H1] set nearby, as it will be referenced when resolving engagements against enemy shipping.

Available Date December 1941 December 1941 December 1941 December 1941 September 1942 December 1941 December 1941 December 1941 December 1941 December 1941 December 1941 December 1941 May 1944 July 1944 December 1944 July 1945 May 1945

Note: When a rule specifies Type A or B subs, it refers only to Type A and Type B specifically, not variants Type A (Mod) or Type B.3.

Chart [K1] keeps track of the status of your Captain and crew, and any skills they may have, which affect game play. The Operations Map shows the different areas of the Pacific in which your submarine will be operating, along with any extra travel time required to reach distant patrol zones.

[4.2.3] You may be reassigned or elect to choose a newer model of submarine under some circumstances, but typically you will remain and captain the same boat until the end of game or until sunk.

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[4.3] PREPARE PATROL LOG SHEET

[4.4] SUBMARINE DISPLAY MAT SETUP

[4.3.1] Prepare a narrative of your submarine career by recording the following information in the header of the Log Sheet:

[4.4.1] Place in front of you the Submarine Display Mat that corresponds to the submarine type selected (see example below). You will be referencing this display continuously while conducting patrols to record the status of your boat and crew.

Submarine Type: this is the submarine class (type) you have selected.

[4.4.2] Place the following markers on your Display Mat:

ID: this is generally designated as “I-###.”

1. Place the Trained Crew Quality marker in the Crew Quality box. This is your starting Crew Quality.

Captain: this is the name you select as Captain of the submarine.

2. Place your Submarine marker in the At Port (Refit) box (located on the left side of the mat) and the current patrol marker on the map at your port.

Note: the ID and Captain’s name have no impact on game play other than building a narrative around your career to enhance your game session or after-action reports. Optional: see 11.6 for Historical Boat IDs.

3. Place the appropriate Torpedo and Deck Gun Ammo markers in the armaments section of your Display Mat (4.5 and 4.6).

[4.3.2] The Log Sheet is used to capture information about each patrol assignment, including which target ships may have become damaged or sunk, in helping determine your victory level (5.2).

4. Place starting Base marker on the mat.

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and Aft Reloads Boxes. Note the total capacity for the Reloads Boxes and make sure the number of torpedo markers equals the capacity value.

[4.5] TORPEDO LOAD Commentary: Japanese submarines normally carried a full load of 21” Type 95 oxygen-driven torpedoes. These were the submarine version of the dreaded “Long Lance” ship-borne torpedo, and left a minimal trail. However, at the start of the war, stocks of older Type 89 and Type 6 steam torpedoes needed to be used up. During the war, an electric torpedo, the Type 92, was developed. The old steams and the oxygen driven torpedoes ran faster than the electrics, and were therefore a bit more accurate. The electrics were slower, and therefore a bit less likely hit at longer ranges, but left no telltale wake of steam bubbles to lead the escorts back to the submarine. This made them much better than the steams and a bit better than the oxygens for use during the day in order to decrease the possibility of detection by escort. The electrics, while seemingly inferior to the oxygen driven Type 95s, were cheaper and easier to make. Midget submarines used a scaled down torpedo of 18” diameter, the Type 97.

8. The total number of torpedoes loaded will always equal the boat’s capacity. Exceptions: (7.4) Transport Special Mission, (7.6) Evacuation Special Mission, (7.10) Mine-laying Special Mission. 9. Torpedoes, once loaded and placed on the Display Mat, may never be swapped out or transferred between Forward and Aft positions. Only reloading is possible. 10. Once torpedoes are fired from the Forward/Aft Tubes the tubes may be reloaded after combat. Forward Torpedo Tubes are reloaded with torpedoes contained in the Forward Reloads Box. Likewise, the Aft Torpedo Tube is reloaded with torpedoes contained in the Aft Reloads Box. 11. Midget submarines always carry two x Type 97 18” torpedoes. There are no reloads for midgets. Reloading can only occur if torpedo markers remain in the corresponding Reload Box. Once the Reload Box for a given section is spent, no more reloads are possible while out on patrol.

PROCEDURE 1. Consult the initial Torpedo Load information in the Submarine Display Mat.

[4.6] AMMO MARKERS

2. Select a total number of torpedo markers that corresponds with the total torpedo load count. 3.

Until 7/42, all Kaidai (KD) classes and Type B classes must load 12 x Type 6 torpedoes. The rest of the load will be Type 95 oxygen torpedoes.

Until 7/42, all other submarine classes must roll 1d6. On a result of 1-3, they must load 12 x Type 89 torpedoes with the rest of the load being Type 95. On a result of 4-6, they will load all Type 95 oxygen torpedoes.

[4.6.1] The Display Mat is used to track the total number of Ammo rounds available for the Deck Gun, up to its stated capacity. [4.6.2] Initially place sufficient Ammo markers in the Ammo box for the Deck Gun so the point value equals the total Ammo capacity listed. [4.6.3] Each Ammo marker point value represents one Ammo round for gunnery combat. Up to two Ammo points (or Ammo rounds) can be expended per combat round per deck gun.

Starting in 7/42 the stocks of older torpedoes are assumed to be used, but the electrics are now available in quantity. All classes may load up to 6 x Type 92 torpedoes with the rest of the load being Type 95.

Note: Each “round” of deck gun ammo in the game represents roughly 25 actual rounds. [4.6.4] Bomb markers represent the small bombload sometimes carried by the float-planes, available on certain classes of submarine. These are only loaded on the Aircraft Display Mat if the submarine has been given a bombing mission.

Example: Type A Class carries a total load of 18 torpedoes. Of these, the starting mix by torpedo type before 7/42 would be 12 x Type 89 torpedoes and 6 x Type 95 torpedoes if a 1-3 was rolled. It would be 18 x Type 95 torpedoes if a 4-6 was rolled. Starting in 7/42, the load would be up to 6 x Type 92 (player’s choice) and the rest Type 95.

[4.6.5] Ammo markers are not used for AA guns since they have unlimited ammunition supply (for game purposes).

6. Place the individual torpedo markers in the numbered Forward and Aft Torpedo Tube boxes. Only one torpedo marker may be placed per box. 7. Place the remaining torpedo markers in the Forward

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Note: AA guns do not have an Ammo box associated with them; only the status of the gun is tracked on the Display Mat.

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[4.7] BASING

[4.8] TRAINING SCHOOLS

Players will be based at one of five bases throughout the game:

Players will attend the Submarine School at Kure (and possibly Midget Submarine School and the Kasumigaura Naval Air School) before starting the game. The schools provide possible skills to start the game for the various crew members and captain.

[4.7.1] YOKOSUKA

This was one of Japan’s major naval bases. All starting boats are considered to begin here.

[4.7.2] PARAMUSHIRO

Set up Chart [K1] with your starting Rank (LT Cdr, 8.9.1) and any relevant markers gained from the appropriate training schools.

This was the major northern Japanese base. It was the base that Aleutians patrols generally originated from. If assigned to an Aleutians patrol and not currently based in Paramushiro, a boat is first reassigned here, then goes on patrol. All further patrols will be to the Aleutians until 7/43, at which time any submarine stationed here is then reassigned to Truk.

[4.8.1] KURE SUBMARINE SCHOOL – CHART [F1]

The player should roll for training for himself, his XO, and his engineer. Any skill markers earned are placed on Chart [K1]. Additionally, the player must choose one of three ways to spend his spare time at school, each of which gives a different game benefit. You can only choose one of the three options.

[4.7.3] TRUK Truk was arguably Japan’s key central base in the Pacific. It ceases to be a base on 3/44, any boats stationed there must re-base to Yokosuka if their patrol would end on 3/44 or later. If refitting at Truk when 3/44 occurs, the boat is assumed to be lost and the player loses one month while he travels to Yokosuka and receives a new boat of his choice (if available yet).

[4.8.2] MIDGET SUBMARINE SCHOOL – CHART [F2]

The player should roll here, but only if his submarine is equipped with a midget submarine (Type C Class). The skills actually pertain to the Midget Sub commander who travels on board your submarine until the midget is launched, but are tracked on the [K1] Captain and Crew Skill Status Chart. If your midget commander is killed or lost, you get a replacement during your next refit. He will also attend school first. The midget submarine is only carried if the current patrol has a Major Event marker and that marker has a Midget Sub mission on the back.

[4.7.4] NEW GUINEA There were several bases that serviced submarines in the New Guinea area, most notably Rabaul and Shortland. Bypassed by the Allied strategy of “Island Hopping,” they remain active until the end of the war.

[4.7.5] DUTCH EAST INDIES (DEI)

[4.8.3] KASUMIGAURA NAVAL AIR SCHOOL – CHART [F3]

Japanese forays into the Indian Ocean were staged from the Dutch East Indies. Several bases were active, and “DEI” represents any of them, including Singapore, Penang and Sabang.

[4.7.6] AIR RAIDS ON PORTS Starting in Jan 1944, during Refit, you must check for air raid damage while in any port except Paramushiro. Roll 2d6: Air Raids on Ports Roll Air Raid Result 2 Boat destroyed in an air raid. Spend one month to transfer to a new boat at Yokosuka. 3 Boat heavily damaged in air raid. Add 2 months to current refit. 4 Boat damaged in an air raid. Add 1 month to current refit. 5-12 No effect.

The player should roll here, but only if his submarine is equipped with aircraft. The skills pertain to the aircraft pilot(s), but are tracked on the [K1] Captain and Crew Skill Status Chart. If you have several aircraft, roll separately for each one’s pilot. If any pilots are lost, replacement pilots arrive during your next refit, but again, attend school first.

[4.8.4] KAITEN TRAINING SCHOOL – CHART [F4] The player should roll here, but only if going on a Kaiten mission. Additionally, as these were suicide missions, you roll for a new set of possible skills before each Kaiten patrol, as your previous Kaiten operators are all dead.

5.0 How to Win the Game GENERAL RULE A full game consists of completing numerous patrols up to and through July 1945. The game may end early if your

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submarine is sunk, or if you as Captain are killed in action or taken prisoner after scuttling your submarine.

and commanders. You are often mentioned in the nation’s papers and are offered command of a Sen-Toku Class in 1945.

While the results of each patrol may result in promotion and crew advancement (or conversely, a drop in crew quality due to poor performance,) the overall victory level is determined at the end of play based on total tonnage of ships sunk.

DECISIVE VICTORY—100,000+ tons sunk: You are the scourge of the seas and the pride of the entire Navy. Your legendary exploits place you at the top of the submarine elite and are mentioned prominently in propaganda efforts. Your peers are amazed at your bold successes. After the war, you return to the fire-bombed ruins of your home city and wonder what it was all for.

[5.1] ENDING THE GAME [5.1.1] The game ends upon completion of your final patrol leading up to or through July 1945—no patrol assignments are conducted after July 1945.

[5.2.3] Your level of victory is shifted up one level for every 10 successful special missions you have accomplished.

[5.1.2] If it is determined after calculating the Refit Period that your next patrol assignment would commence after July 1945, the game ends.

[5.2.4] Should you be killed in action as captain, you still (posthumously) determine your victory level. The same applies if you are taken prisoner.

[5.1.3] The game immediately ends, regardless of date, should you as Captain be killed in action or taken prisoner.

6.0 Sequence of Play

[5.1.4] Once the game has ended, you can determine victory.

GENERAL RULE

[5.2] DETERMINING VICTORY

Sensuikan adheres to a discrete sequence of play for conducting numerous submarine patrols. At its most abstract level, the sequence revolves around conducting patrols with a Refit action at the end of each patrol. While there are no discretely numbered “game turns” as with other turn-based systems, game play is broken down into monthly increments of time, as reflected by the Log Sheet. The game begins on the availability date of the submarine type selected (first patrol assignment) and patrols are carried out up through 7/45. Each patrol takes at least one month to complete, while the number of months required to complete refit can vary by circumstance (Submarine class, amount of damage, and/or crew injury).

[5.2.1] Consult your log sheet at the end of play and add up the total tonnage of ships sunk during your career. [5.2.2] Based on the total tonnage of enemy warships and shipping sunk, your victory level (adjusted by special missions) and performance as submarine captain can be determined below. DEFEAT—0-9,999 tons sunk or your submarine is captured due to unsuccessful scuttle attempt: Note: the moment your submarine is captured due to unsuccessful scuttle attempt, this results in an automatic “Defeat,” regardless of tonnage amount for ships sunk and special missions performed.

The following game play outline begins once a submarine has been selected and the corresponding Display Mat has all markers placed (4.0, Game Setup).

You are a disgrace to the Emperor, your ancestors, your family, and yourself. If you have survived, you return home to the fire-bombed ruins of your home and contemplate your mistakes.

GAME PLAY OUTLINE

DRAW—10,000-19,999 tons sunk:

1. DETERMINE ACTIVE MAJOR EVENTS AND PATROL ASSIGNMENT

You have fulfilled your obligations to the nation. Your neighbors cast sideways glances at you times.

MARGINAL VICTORY—20,000-49,999 tons sunk: You have enjoyed a modicum of success as a submarine captain. Your crew respects your abilities. SUBSTANTIAL VICTORY—50,000-99,999 tons sunk: You are one of the Imperial Japanese Navy’s top submarine elite, and have gained the respect of your peers, your crew,

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A. Place any active Major Event markers on the map on the appropriate areas. For a game starting on December 1941, these would be Pearl Harbor, Dutch East Indies, Malaya, and the Philippines. Remove any Major Event Markers that have expired. B. Consult Patrol Assignment Table [A1] for your current assignment.

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C. Enter patrol assignment on the Log Sheet (on row corresponding to patrol start date) and check for special mission assignment if the patrol is to an area with an active Major Event marker. If your submarine is capable of performing that type of special mission, that is your assignment. If your submarine cannot perform any of the listed special missions, it simply is on patrol to that area. Special Missions are listed on the back of each Major Event marker. D. Place submarine Marker on the map at the first Travel Box of assigned patrol.

B. Check for encounters for each Travel Box occupied by consulting the [A3] Encounter Chart.

RESOLVE ENCOUNTER a. Determine Random Event (if rolled, Chart [B11]), or resolve Air or Ship Encounter (8.0). Engaging enemy ships in combat is always voluntary. b. You may perform additional rounds of combat as necessary against unescorted ships (8.2.8) or attempt to “Follow” escorted ships or Convoys (8.4) until the encounter is completed, reloading torpedoes between instances.

CONDUCT PATROL

A. Patrols consist of traveling a number of travel boxes, possibly conducting a special mission, and then returning to base. Travel boxes come in two types: “Transit Boxes” (traveling long distance with low chance of contact) and “On Station” boxes. Every patrol starts (and ends) with one Transit Box, as shown on the Submarine Mat. Any special mission will be performed in the first On Station travel box.

c. Additional rounds of combat may also occur should your submarine be detected and undergo repeated depth charge attacks. This cycle repeats automatically until your submarine escapes Escort Detection, or is sunk. d. Attempt to repair any damaged submarine systems once all combat rounds are completed (8.5).

Some patrol areas are fairly distant from Japan, and travel there will entail additional Travel Boxes (shown on the Operations Map, but not shown on the Submarine Mats). These areas are Pearl Harbor, the West Coast of the US, Australia, the Panama Canal, and Europe.

Note: Following damaged ships is still allowed once you escape detection, even if you have been in many rounds of depthcharging.

Important Note: These additional Travel Boxes on the Operations Mat decrease the number of On Station boxes for that patrol, and are divided in half to the front and end of the patrol (if there are 3 extra Transit Boxes, it divides as 2 in the front and 1 at the end). Example: A Type C Class is starting the war by heading to Pearl Harbor. The Type C mat has a Transit Box, five On Station boxes, and a final Transit Box. Because of the extra transit boxes to Pearl Harbor, this patrol actually works out to be two Transit Boxes, three On Station boxes (the first of which is when the Midget Sub is deployed) and then two final Transit Boxes. Had the Type C been sent to the West Coast of the US, the patrol would be three Transit Boxes (1 normal +2 extra), followed by two On Station boxes, followed

As a final example, if the Type C starts the war going to the Dutch East Indies, the patrol looks exactly like the submarine mat, as there is no additional transit time. Therefore it would be one Transit Box, five On Station box, and a final Transit Box.

If no encounter occurs, repeat this step for next Travel Box entered. If encounter is rolled, follow steps below:

Map Note: Several patrol areas on the map involve a much lengthier transit to arrive at than others. (Australia, Europe, Hawaii, US West Coast, etc). The map shows additional transit boxes for these areas. Players should check for encounters for these on map-transit boxes in addition to the transit boxes on his Submarine Display Mat.

by the final 2 Transit Boxes (1 normal +1 extra).

C. Proceed to next Travel Box and repeat until your submarine enters and resolves any possible encounter for your final Travel Box. Upon completion, place the submarine marker in the In Port (Refit) Box. Note on Terminology: All boxes on the map are travel boxes. However, some travel boxes are referred to as “transit” boxes – they occur at the start and end of a patrol. The travel boxes at the mission patrol area can be referred to as “on station travel boxes.” The first non-transit travel box is sometimes called the “Mission box.” Regardless, they are all still travel boxes.

REFIT SUBMARINE

A. Assess submarine damage and duration required (8.5.10) to complete all repairs. Record refit duration on Log Sheet by placing an “R” on each refit month, to determine when next patrol will begin. Notice that different classes of submarine have different lengths on patrol – some are two-month patrols, some are

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three-month patrols. To reflect this, add a “P” in the month below your patrol assignment month for boats with 2-month patrols, and add another “P” in the month below that one for boats with 3-month patrols. This indicates the boat is still out on patrol for those months. After the bottom “P” month, place an “R” for each month of refit required. Normally this is one month, but may be longer due to damage to the boat.

on the counter. Some Special Missions (those involving aircraft, midget submarines, or kaiten) require use of the appropriate module.

[7.1] RECONNAISSANCE A reconnaissance mission requires an aircraftequipped submarine (only) to launch its aircraft and conduct reconnaissance (notionally) in the area. Not all classes, therefore, will be able to conduct this mission. Resort to the Aircraft Module when you arrive at the first non-transit patrol box (the “Mission” box). After resolving your aircraft’s mission per the module’s rules, the mission is successful if one or more of your aircraft survives (whether it is recovered or not). It is considered to be recovered in the same travel box if it passes the recovery roll.

Note: if the next patrol start date is after 7/45, the game ends. B. Check for Crew Recovery and possible replacement (8.5.9.1). C. Check for Crew Advancement (8.7).

D. Check for Awards and/or Promotion (8.8 and 8.9). E. Check for possible submarine Reassignment (9.0).

[7.2] PICKET LINE

F. Replenish and set Torpedo Loads (4.5) and replenish Ammo markers (4.6) in anticipation of the next patrol. All damage and crew injury markers should be removed from the submarine Display Mat in anticipation of the next patrol assignment.

This mission requires the submarine to be part of a picket line, hoping to intercept American forces heading toward or away from an area. Essentially, the submarine remains stationary, hoping to find a warship target. In game terms, the major impact of being on a picket line is the submarine is not permitted to engage or follow any merchant shipping it may encounter. Success for picket line duty requires one warship or Capital ship to have been engaged (not necessarily sunk).

G. Check for possible Deck Gun/Aircraft Removal and Kaiten installment (7.12).

H. Check for possible damage from bombing starting Jan 44 (4.7.6).

Game play is conducted per the above sequence and is repeated until the game ends (5.1, Ending the Game), at which time victory can be determined (5.2, Determining Victory). The precise activities performed as outlined above are covered in the appropriate rule sections.

[7.3] MIDGET SUBMARINE ATTACK

7.0 Special Missions and Major Events There are numerous special missions in the game, reflecting the Japanese high command’s concepts on the use of their long-range submarines. These missions are tied to the active Major Event markers on map. If assigned to a patrol where a Major Event is currently active, the submarine will have a special mission, which occurs in the first non-transit travel box of the patrol. If a submarine’s patrol assignment is to an area where there is not a Major Event ongoing, or it is incapable of conducting the type of special mission required, then it conducts a normal patrol. Special Missions, when completed successfully, count as TWO successful patrols, not just one, for the purposes of skill purchase and crew advancement. This also applies to a patrol to an area with a Major Event marker if that marker says “Patrol” even though such a patrol is not technically a Special Mission. If a submarine is capable of performing more than one Special Mission that is listed on the back of a Major Event marker, it is assigned the first mission listed that it is capable of, working from top to bottom

This mission requires the submarine to drop off its midget submarine close to a harbor, whereupon it conducts an attack against warships moored there. This mission is considered a success if the midget submarine is dropped off and at least attacks one ship – any damage it may or may not inflict is immaterial for success. It does not need to survive. However, any tonnage the midget submarine manages to sunk IS added to the submarine’s total for victory point and awards purposes. The mission is also a failure if the midget submarine is unable to be deployed (due to damage to the midget themselves, or death/serious wounds on the midget crew before arrival to the mission box). Whether or not the midget submarine actually damages any shipping or warships is, again, immaterial for the purposes of calculating mission success. It only matters that it at least deployed and engaged something. Midget submarine attacks are processed by consulting the Midget Sub Module.

[7.4] TRANSPORT Successful accomplishment of this type of special mission requires delivery of supplies (to Guadalcanal or New Guinea, for example). When assigned to transport supplies, a submarine has its torpedo tubes loaded, but carries no reloads. Place the “Supplies” marker in the

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reload area. To deliver the supplies, the submarine must roll on the Special Missions Encounter column of Chart [A3] upon arrival in the first non-transit patrol box (similar to the process for a reconnaissance mission). If there is no encounter, the supplies are delivered and the mission is successful. If there is an encounter, it is resolved then the player rolls again until there isn’t an encounter and the mission is completed.

[7.8] KAITEN ATTACK This mission requires a player to drop off its kaiten close to a harbor, whereupon they conduct an attack against warships moored there. This mission is considered a success if the kaiten are dropped off without the player’s submarine having been detected – any damage they may or may not inflict is immaterial. The mission is also a failure if no kaiten are able to be deployed (due to damage to the kaiten themselves, or death/serious wounds on the kaiten crew, before arrival to the mission box). However, any tonnage kaiten manage to sunk IS added to the submarine’s total for victory point and awards purposes. Kaiten attacks are resolved by using the Kaiten Module. As a suicide weapon, the kaiten and crews are considered lost regardless of any targets hit or missed. Kaiten missions are performed by consulting the Kaiten Module once the submarine arrives at the Major Event marker location.

[7.5] STRATEGIC TRANSPORT (EUROPE) This mission only applies to Type A and Type B submarines, all others re-roll. These were codenamed “Yanagi” (translated as Willow) missions. You have been chosen to deliver strategic minerals and supplies to a German-controlled port in France. Head to the Transit Boxes in the Indian Ocean pointing toward Europe, then roll once per box for an encounter on the Special Mission/ Additional Round of Combat section of Chart [A3]. You have now arrived in Europe. Reverse the process to return to Japan. This patrol is assumed to last 3 months in each direction. The patrol is considered a success if the supplies are delivered to Europe.

[7.9] SHORE BOMBARDMENT

[7.6] EVACUATION Evacuation missions require the submarine to travel to the Aleutians and help evacuate Japanese personnel from the islands. When assigned to an evacuation mission, a submarine has its torpedo tubes loaded, but carries no reloads. The submarine must roll on the Special Missions encounter section of Chart [A3] upon arrival in the Aleutians, as they are more vulnerable while loading. If there is no encounter, the passengers are loaded and the patrol is a success assuming you arrive back at base with the passengers in an unwounded status. If there is an encounter, it is resolved then the player rolls again until there isn’t an encounter and the mission is completed. The Passenger counts as a Pilot on the Crew Injury Chart.

[7.7] BOMBING MISSION Although somewhat ill-conceived, some forests in Oregon were bombed by submarine launched aircraft in the hope of causing large forest fires. Late in the war, a plan to bomb the Panama Canal was also considered. To conduct either mission, the submarine must travel to either the West Coast or the Panama travel box as appropriate, then launch their aircraft and conduct the bombing run per the Aircraft Module. The mission is a success if bombing occurs, even if no ships were sunk on the rest of the patrol and even if aircraft are lost. If no bombing occurs, the mission is considered a failure, even if other ships were sunk on the patrol. Only the Type A (modified) and the Sen-Toku classes will ever be assigned the mission to bomb the Panama Canal.

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Shore bombardment requires the submarine to surface within deck gun distance off the US West Coast and expend all deck gun ammunition (this is notionally achieved by simply removing all deck gun ammunition markers) and is successful if the submarine returns to base. Again, like most other special missions, a roll on the Special Mission section of the [A3] Encounter chart occurs before the attempt, and any encounter must be survived before the shelling may occur. If there is an encounter, it is resolved then the player rolls again until there isn’t an encounter and the mission is completed.

[7.10] MINE-LAYING This mission requires that mines are carried loaded in the torpedo tubes. This reduces the boat’s torpedo load by as many tubes as it has. Once the mines have been successfully delivered, the tubes may be reloaded with torpedoes. Notice that the Kirai-Sen class is a specialized minelayer, and has special mine-laying compartments with the mines laid out the back of the boat from an aft dispenser. This class does not reduce its torpedo load on a mine-laying patrol, and in fact, every patrol with a Kirai-Sen class is automatically a mine-laying mission, regardless of what the Patrol Assignment chart says. Kirai-Sen class submarines do NOT get credit for two successful patrols for conducting mine-laying, unlike other classes. To conduct a mine-laying mission, the submarine travels to the first on-station travel box. When it arrives, it rolls on the Special Mission section of the [A3] Encounter chart. If no aircraft arrives, it is assumed to lay the mines. If an encounter occurs, the player conducts it, and rolls again until it is finally clear and the mines can be laid. After the mines are laid, the rest of the patrol is

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conducted normally, and the patrol is considered a success whether or not any tonnage is sunk.

[7.11] PASSENGER DELIVERY This mission requires the drop-off of a V.I.P. passenger to a location (either New Guinea or India). To conduct a Passenger mission, the submarine travels to the first on-station travel box. When it arrives, it rolls on the Special Mission section of the [A3] Encounter chart. If no aircraft arrives, it is assumed to have successfully dropped the passenger via rubber boat. If an encounter occurs, the player conducts it, and rolls again until it is finally clear and the passenger can be dropped off. After the passenger is dropped off, the rest of the patrol is conducted normally and the mission is a success. If by bad luck the passenger is killed or seriously wounded before drop-off, the mission is a failure. The Passenger counts as a Pilot on the Crew Injury Chart.

[7.12] DECK GUN/AIRCRAFT REMOVAL AND KAITEN As the war progressed, the Japanese were taking desperate measures to turn the tide of events. One such measure was the installment of “Kaiten” suicide manned torpedoes to the decks of some submarines, which would carry them close to American ships at harbor and then release them as sort of a manned torpedo “kamikaze.” In order to make room for them, certain classes had their deck guns and/or aircraft removed. These classes have notations on their Submarine Display Mats to indicate the date on which this occurs. Once removed, deck guns are not reinstalled, even if later missions do not involve kaiten operations.

[7.13] SPECIAL MISSION COMPLETION If completed, a Special Mission counts as two Successful Patrols for the purposes of crew advancement, whether or not any ships were sunk that patrol. Failure to complete the special mission results in no credit for a successful patrol, even if ships were sunk at some point. This double credit for Special Mission completion does not apply Kirai-Sen class minelayer, which has a mine-laying mission every patrol.

[7.14] MAJOR EVENT MARKERS There are 27 Major Event Markers for use during the game: Front

Back

At the start of each patrol, new markers that are active are placed on the map (by date) and markers that have expired are removed. The front of each Major Event has the historical title (Pearl Harbor, Indian Ocean, Midway,

etc). along with the dates by month and year that the event is active. The back of the markers includes a listing of one to three special missions available for that Major Event. Submarines assigned to patrol an area with an active Major Event Marker will, instead of conducting a normal patrol, conduct one of the special missions above that is listed on the back of the event marker. The player will check the special missions in order on the Major Event marker and conduct the first one listed, from top to bottom, that it is capable of performing. It is possible a submarine cannot conduct such a special mission. For example, a marker listing a “Midget Submarine Attack” cannot be performed by a submarine class that does not carry a midget. A “Bombing” special mission cannot be performed by a submarine that does not have an aircraft, etc. If none of the listed special missions on the back of the Major Event Marker can be conducted by your current submarine, the event marker is ignored and the submarine conducts a normal patrol. However, some Major Event markers have a Patrol mission listed on the back. Despite the fact any submarine can conduct those, they still count as a Special Mission for the purposes of earning two successful patrols.

[7.15] AIRCRAFT LAUNCH AND RECOVERY Aircraft can be launched in the game from hangar-equipped submarines (Types A, A (Modified), B, B. 3, Junsen J. 2, Junsen J. 3, and SenToku). They were kept disassembled in watertight hangars topside, assembled, and launched. Normally, they will be launched and recovered in the same Travel Box. However, several issues may arise to preclude this. An aircraft cannot launch if its Pilot is SW or KIA. An aircraft cannot launch if the hangar is damaged or inoperative. Each time a hangar is damaged, it is assumed to destroy one of the submarine’s aircraft (some Japanese submarines carried up to 3 aircraft). If the hangar is repaired, any surviving aircraft can be then launched. A damaged or inoperative crane does not preclude launching an aircraft, it simply means the aircraft cannot be recovered. Aircraft launch requires a die roll per the Aircraft Module, even if you are not on a Special Mission and are just using the aircraft for scouting. Aircraft can be launched even if not on a Special Mission, for the purposes of scouting. If you do so, you get an “extra” encounter roll for this Travel Box. If, however, the encounter roll is an aircraft encounter and your aircraft is aloft, it is automatically considered lost. Launch and Recovery are not automatic, and are rolled with Charts [P1] and [P2] respectively, from the Aircraft Module.

[7.16] THE MIDGET SUBMARINE MODULE This module only applies if a submarine is equipped to carry a midget submarine, and is

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assigned to conduct a midget submarine attack as listed on a Major Event marker.

5. Once the final Transit Circle has been checked for encounters, roll 1d6 to recover the midget submarine. On a roll of 1-3 it is considered lost; on a roll of 4-6 it has been recovered (see Chart M7).

If carrying a midget submarine, conduct Midget Submarine Training School, Chart [F2], for the commander of the midget before setting off on patrol. Do this every patrol you have a new commander, if the previous one is killed in action.

6. After the recovery attempt, the player should revert back to his standard Submarine Display Mat and the Patrol Map, and continue his patrol.

There are 4 midget attacks in the game: Pearl Harbor (M1), Sydney Harbor (M2), Diego Suarez (M3, in Madagascar) and Guadalcanal (M4). When assigned to conduct this mission, the submarine heads to the Major Event marker’s location normally, rolling for encounters along the way. At the Major Event location, play then switches to one of the four harbor maps (Charts M1 through M4) and play continues with the Midget Sub Display Mat. Notice the harbor maps have Travel Circles (as opposed to Travel Boxes) which merely serves as a reminder to the player he is now operating at a smaller scale. Once at the Major Event Marker, plays continues according to this sequence: 1. Place the Midget Sub Display Mat in front of you, with 2 Type 97 torpedoes and any other applicable markers on the mat earned from the training school. Also place the midget sub counter in Transit Circle 1, on Chart M1 through M4, as appropriate for the current mission.

Note: The term “Escorts” used above in the Midget Submarine Module technically refers to any of a variety of small AntiSubmarine Vessels (ASVs) but I use the term “Escorts” to match terminology in the main game’s combat rules to reduce confusion.

[7.17] THE AIRCRAFT MODULE This module only applies if your class of submarine is equipped with one or more aircraft on the deck, disassembled in watertight hangars. If you do, the first step, if you have not already done so, is to roll for your pilot(s) to attend Flight School (Chart [F3]). This may allow them special skills or abilities for use while on missions. An aircraft mission may occur if assigned to an area with Major Event Marker and it has either Reconnaissance or Bombing as a listed Special Mission. Once at the Major Event Marker, plays continues according to this sequence: 1. Place the Aircraft Display Mat in front of you, with any other applicable markers earned from the training school. Also place the appropriate aircraft counter in transit circle 1, on Map P7 through P12, as appropriate for the current mission. (The numbers on the back of the Major Event markers for Bomb and Recon missions tie to these maps).

2. Move from circle to circle, rolling on the Midget Sub Encounter table once for each Transit Circle (including the first) and once in the Target Circle, and resolve encounters in each circle before moving to the next. In some harbors, there are detector loops (which may generate an escort attack after moving past it) and/or antisubmarine nets (which may also generate an escort attack, or possibly ensnare the midget).

2. Take off by rolling 2d6. On a roll of 2 or 12, roll on Chart [P1], the Mishap/Malfunction table.

3. Midget Subs have their own encounter tables for use with Transit Circles and Target Circles. Transit Circle encounters will sometimes require you to consult Chart [M6], the Midget Submarine Event Table. 3. All midget submarine attacks occur while submerged, regardless whether it is day or night. Additionally, midget submarines cannot utilize the “exceeding test depth” game mechanic. All attacks and detection rolls are made using the standard game rules otherwise, with the exception that attacks against stationary targets (in the Target Circle) are made with a -1 “to hit” drm on Chart B1, and a -1 damage drm on Chart B3.

3. Move from circle to circle, rolling for encounters in each one (starting with Transit Circle 1). Use the encounter results listed on either the Transit, Recon, or Target column on Chart [P3] as appropriate. An aircraft damaged by another aircraft or AA fire must abort. Bombing occurs in the Target Circle on a bombing mission by utilizing Chart [P6]. 3. After rolling for an encounter in the final transit circle (and resolving it, if need be) you then roll for recovery by the submarine on Chart [P2.] If the recovery fails, the crew and plane are lost. If the boat’s crane is inoperable, the plane cannot be recovered; however, if the recovery roll succeeds in this case, the crew is recovered (they are fished out of the water and the plane left behind).

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4. If your pilot is killed (or missing in action) roll a new pilot through Flight School the next time you are in port and pick up a new aircraft. KIA/SW rear gunners are simply replaced at port. 5. The Type A (Mod) class of submarine has two aircraft. For air operations with that class, you would conduct Flight School two times, and each pilot would be awarded separate skills depending on your choices. The same procedure applies to the Sen-Toku Class with its three aircraft. Note on Terminology: “A/C” stands for “Aircraft” when found in the rules or on the charts.

[7.18] THE KAITEN MODULE Another difficult-to-translate word, “kaiten” means literally “turn the heaven” but is more closely translated here as “turn of the Heaven’s will” or “the Heaven Shaker.” Kaiten were manned suicide torpedoes. Similar to the concept of “Kamikaze” aircraft, kaiten were specially modified torpedoes, with extra-large warheads, guided by a trained suicide operator to the target. Several classes of submarine were modified to usually carry six on the deck, although some carried less. Sounding good in theory, kaiten were not very successful in practice. Difficult to steer and operate, many had mechanical issues and flaws, which sometimes led to failure to launch, and, more unpleasantly, early detonation. A few harbor penetrations did lead to successes, but, overall, it was a wasteful program. Only 3 American ships were confirmed sunk or damaged by kaiten, for a loss of over 100 kaiten pilots. This module only applies if a submarine is equipped (or can be equipped) to carry kaiten, and is assigned to conduct a kaiten attack as listed on a Major Event marker. There are five kaiten events in the game: three against Ulithi Harbor (K2) and two considered to be in open water (K3) near Iwo Jima and Okinawa. When assigned to conduct this mission, the submarine heads to the Major Event marker’s location normally, rolling for encounters along the way. For each of the kaiten, conduct the Otsujima Kaiten Training School, Chart [F4] by choosing a benefit for each pilot. The chosen benefits apply to only that kaiten pilot; they do not need to all be the same benefit. At the Major Event location, play then switches to one of the two kaiten maps (Charts K2 and K3) and play continues with the Kaiten Display Mat. Notice the kaiten maps have Travel Circles (as opposed to Travel Boxes) which merely serves as a reminder to the player he is now operating at a smaller scale. Once at the Major Event Marker, plays continues according to this sequence:

1. Place the Kaiten Display Mat and one of the two Kaiten map (K2 or K3, as appropriate) in front of you. Attempt to launch your kaiten one by one, by rolling a 1d6 1-3 for success. On a 4-6 the kaiten fails to launch for mechanical reasons. Next, check for premature detonation. On a 1d6 roll of 6, the kaiten explodes early and is removed from the map. Place each kaiten that launches and survives the early detonation roll on the Transit 1 circle. 2. Move from circle to circle, rolling on the Kaiten Encounter table once for each Transit Circle (including the first) and once in the Target Circle, and resolve encounters in each circle before moving to the next. If attacking Ulithi Harbor, each kaiten must roll to cross the atoll reef, with success on a 2d6 roll of 9+. Failure results in a lost Kaiten. Perform this check first upon arriving in the Target Circle, then roll for an encounter. 3. Roll for escort detection upon reaching the Target Circle. If the kaiten is undetected or survives any detection, roll for targets. Then choose your target. Any Kaiten that have survived this far roll to hit. If they hit, they have one final check, a dud check per chart [B2]. Kaiten that explode do +2 points of damage (meaning anywhere from 3 to 6 points). Note: Kaiten warheads were significantly larger than the Type 93 Long Lance torpedoes they were based on. 4. Once all Kaiten have exploded or failed to launch, the mission is complete and play reverts to the main game’s maps and charts. The player now must roll on the Additional Round of Combat section of the main game’s Encounter Chart. After resolving any encounters, the player should continue his patrol.

8.0 Combat [8.1] GENERAL PROCEDURES [8.1.1] Combat Rounds. Combat is resolved for each travel box in rounds, with each round composed (possibly) of several turns. There MAY be additional rounds of combat as well, if the encounter is not completed in the first round of combat. This is at the submarine captain’s whim; he is not forced to continue chasing a damaged ship, for example. [8.1.2] No Encounter. If there is no encounter rolled for a particular travel box on Chart [A3], then nothing occurs. Move the submarine one travel box ahead on the map and roll again. Radar-equipped submarines get a second chance for an encounter if the first roll was a “5” if the radar is operational.

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[8.1.3] Ship Encounters. If a SHIP is rolled for the encounter, roll 1d6 to determine size. This is the easiest encounter for the Submarine to handle...a ship traveling alone. 1-4 is a small ship, 5-6 a large ship. It is possible also to roll “SHIP(S)+ESCORT” in which case it is a lone ship or two, but does have escort. After size is determined, roll on the appropriate target chart (T1 or T2) to determine the exact ship(s) encountered. [8.1.4] Capital Ship Encounters. If a CAPITAL SHIP is rolled for the encounter, roll on Chart [T4] to determine which capital ship it is. Capital ships encountered in the Dutch East Indies, Malaya, Indochina, or Indian Ocean are rolled from the British sublist. Such encounters always have escort. Unlike “The Hunters” ALL of these Capital ship targets automatically confer the Order of the Golden Kite (4th or 5th Class, depending on the commander’s rank) if sunk; therefore, they are quite lucrative targets! Capital ship escorts were normally quite heavy, and accordingly capital ships receive a “+1” on the detection chart against you. Also, not all of them are five damage points. Several of the larger battleships require six or seven points of damage to sink. Additionally, like warships targets, some are “Fast Targets” meaning they are harder to hit due to their high speed, and you receive a +1 drm when shooting torpedoes at them. The capital ships which are “Fast Targets” have an indicator on their counter to denote this. [8.1.5] Warship Encounters. If a WARSHIP is rolled for the encounter, roll on Chart [T3] (or [T5] if in the Indian Ocean, Malaya, Indochina, or Dutch East Indies) to determine which warship it is. Warships are always considered to be escorted. Warships are all considered to be are “Fast Targets” meaning they are harder to hit due to their high speed, and you receive a +1 “to hit” drm when shooting torpedoes at them. Additionally, DE, DD and generic escort targets receive an additional +1 “to hit” drm when shooting torpedoes at them due to their small size. This is in addition to their +1 drm for being fast. [8.1.6] Convoy Encounters. If a CONVOY is rolled for, roll three dice to determine the size of the targets closest to your attack position. Then roll for each ship to determine the exact ship encountered. Convoys are also always considered to have escorts. (NOTE: Convoys normally had many more ships in them than a single Submarine could attack. Therefore, only three of the many ships are represented as being in your boat’s “window of opportunity” for that encounter).

[8.1.7] Aircraft Encounters. If Aircraft is rolled as the encounter, roll on Chart A4 and apply any appropriate modifiers. Resolve aircraft encounters as described below in section (8.3). [8.1.8] Random Events. The first natural “12” rolled in a travel box per patrol is not the listed encounter - it is instead a Random Event. Go to the Random Event chart, roll again, and resolve the Random Event. There can only be one random event per patrol, so any further rolls of “12” for a travel box are resolved as the normal listed encounter on the patrol chart. Note: Early in the war, the transit boxes will give no encounters. However, you should still roll to see if a “12” is rolled, which would trigger a random event for that patrol. [8.1.9] Time of Day. Roll one die to determine the time of day: 1-3 is day, 4-6 is night. Night surface attacks can only be performed at night, naturally. During the day, it is also easier to see the tracks of steam driven torpedoes, therefore, a “+1” detection modifier is applied to those attacks. [8.1.10] Switching from Day to Night. If you want to prosecute a contact in the day and you rolled for “night” or vice versa, you may do so by taking a small risk of losing contact. Roll 1d6: 1-4 is successful, 5-6 means the target contact is lost (and so is your encounter for that travel box). You CANNOT switch from day/night or night/day versus a Capital ship (they are simply too fast). Having an operational radar gives the switching roll a -1 drm.

[8.2] ENCOUNTERS WITH SHIPS: ATTACKS AGAINST SHIPPING Once the time of day has been identified and the targets have been identified, the Submarine commander must decide how to attack: [8.2.1] Range Decision. He chooses what range to use, each with some advantages and disadvantages. If he chooses medium or long range, he fires first, with a lesser chance to hit. If he chooses to attack at close range, he must first make a Detection roll on chart [B4], with a 2d6 roll of “9” or less (no modifiers except if the commander holds the Order of the Golden Kite, he gets a -1 to this roll). If still undetected, he may then still fire first. If detected, he is unable to attack and suffers an attack roll on chart [B5]. However, there are no detection rolls made for unescorted ships, so there is no downside to firing from close range in that case. [8.2.2] Night Attacks. If the encounter is at night, the player must also decide if he is prosecuting a night surface

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attack. Although this allows for slightly better torpedo calculations due to the use of optics on the bridge, he will suffer a +1 penalty modifier on the detection die roll. This represents the increasing Allied availability of surface radar. A night surface attack also suffers from a +1 modifier on chart [B5] during the first round of combat, and the boat cannot implement the “exceed test depth” game mechanic in that round, as they are essentially still too close to the surface at that point.

the damage is applied to the Submarine, and additional flooding is checked for on chart [B6], the cycle continues. Roll AGAIN for detection, now applying the “+1” for previous detection AND any new modifiers such as dive plane or fuel tank damage, and if detected again, roll again on Chart [B5]. Rounds of combat continue with detecting/attacking until the Submarine finally escapes detection on chart [B4] or is sunk. Players will notice it can be more difficult to evade detection in subsequent combat rounds, especially if a lot of damage occurs.

A Submarine may fire a “second salvo” from the other end of his boat if he is conducting a night surface attack. However, these torpedoes are fired at +1 to hit. For example, a player can fire all torpedo tubes at a convoy, with the first salvo (normally the front tubes) fired normally, and the aft tubes fired at +1 to hit (additional to any other to hit modifiers).

In “Sensuikan” each cycle of depth-charging may involve a “Special Attack” instead of a normal depth charge attack. On May 1944 or later, before the escort attacks, roll 1d6. On a roll of “1-5” the normal depth charge attack occurs. On a roll of “6” a “Special Attack” occurs instead. If a special occurs, roll the attack using the Hedgehog section of chart [B5]. A special attack does not occur more than once per encounter.

Historical Note: second salvos were not practical while submerged as the submarine would take too long to spin 180 degrees underwater. This is why they are only allowed while conducting a surfaced attack.

[8.2.3] Attack Procedure. The player can choose to fire any/all of his fore or aft torpedoes at any target, but all must be from the same end of his boat (unless firing a ‘second salvo” (8.2.2). All shots are declared before rolling, then roll to see if the torpedoes hit. After hitting, roll to see which torpedoes are duds on chart [B2]. (I use the term “Dud” to represent any malfunction which causes the torpedo to not explode or causes them to explode early. Although fairly reliable, torpedoes were still an imperfect weapon at times). Any torpedoes that hit, and are not duds, then roll for damage inflicted on chart [B6]. It takes different amounts of damage to sink different size ships. NOTE: All Capital ships (regardless of actual tonnage) take 5 to 7 damage points to sink, as listed per ship. [8.2.4] Deck Gun Firing. In addition to torpedo fire in first turn of combat, the Submarine may fire two deck gun shots per deck gun against unescorted ships (each “shot” from a deck gun actually represents about 25 rounds in real life). Notice that deck gun ammunition is limited per patrol. The results of deck gun firing may be assessed before firing the next shot (fire one shot at a time as needed/desired). [8.2.5] Escort Detection. Escorted ships, after the first volley of torpedoes, now have their escorts roll on chart [B4] to try to find the Submarine and attack it. If undetected, the combat turn is ended. If detected, the Submarine immediately undergoes an attack on Chart [B5]. For each “hit” on chart [B5], roll once on chart B5 to determine the damage from the depth charges. After

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Although the Submarine “sneaks” to close range at by rolling an “9” or less on the detection chart, all rolls after combat starts are made at +1 if the boat is at close range. Close range against escorted targets is extremely dangerous, if not outright suicidal, at the later stages of the war. Proceed with caution. [8.2.6] Exceeding Test Depth. Submarines may attempt to slip away from the escorts by declaring they are exceeding test depth... but this is a risky procedure. Before the escort detection roll on table [B4] the player must decide if he is going to attempt to increase his chances to slip away by exceeding test depth and diving deeper than is safe. The Submarine automatically takes one hull damage and then rolls 2d6. If he rolls lower than his current # of damaged hull boxes, the boat implodes and sinks. If he rolls = to his current # of damaged hull boxes, he takes an additional hull damage, and immediately rolls again. (If he only has the single box of hull damage he still has to roll, despite the fact it is impossible at this point for the boat to implode. In that case, if he rolls a “2” he takes another box of hull damage, and immediately rolls again). If he rolls greater than his current number of damaged hull boxes, there is no effect, and the escort detection roll gets a -1 modifier. The Submarine must take an additional hull damage and make a roll for EACH combat round it wishes to get a -1 modifier. You cannot exceed test depth on the first turn after a night surface attack.

Designer’s Note: Taking your boat deeper than it was designed to go is obviously dangerous if you’ve already suffered significant hull damage. However, there may be situations when you have little or no hull damage yet, but have suffered leaking fuel tanks, battery damage, etc. In that case you may wish to consider using this option. Although some players may think they can abuse this by constantly using it, the mandatory 1 Hull Damage means they

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player then rolls for an additional round of combat or disengages per 8.2.9.4. After this “surprise attack” by the enemy sub, the Submarine gets to fire first in any subsequent rounds of combat. Notice the range will be medium in this case.

will always be refitting for at LEAST one extra month per patrol, reducing their time at sea in the long run.

[8.2.7] Automatic Escape. Regardless of how bad the die roll modifiers get for the detection cycle, a roll of a natural “2” (snake eyes) results automatically in a result of “not detected” and the Submarine escapes. [8.2.8] Additional Rounds of Combat. If for whatever reason, an unescorted target was not sunk (or completely missed), the player may choose to initiate an additional Round of Combat by reloading his torpedo tube(s) if desired, and rolling on Chart [A3] under “Additional Round of Combat”. -If no escorts or aircraft arrive, he may again fire torpedoes and/or up to 2x deck gun shots from close range per the normal combat procedure. -If an escort arrives, he immediately must roll for detection on chart [B4]. -If undetected, he may attack per the normal combat rules, and roll for detection again after the attack. He is essentially starting from scratch against the now escorted target. -If detected, he cannot attack and undergoes the normal escort attack procedure. -If an aircraft is rolled for, he must abort his attack, dive immediately and roll per the aircraft encounter rules. Players may have two additional rounds of combat in the same travel box. If they require (or desire) a third additional round of combat, they must first advance the travel box by one and then continue. The same applies for each subsequent travel box (only 3 rounds of combat total per box) although such an occurrence would be extremely rare. You cannot initiate an additional round of combat if that would require you to advance into a transit box, as you need to head to port at that time due to fuel limits. Additional Rounds of Combat are not allowed versus escorted ships, once a combat round is complete. Instead, the player may choose to try to finish off any ships by using the “Following” game mechanic instead. [8.2.9] Special procedure for encounters with enemy submarines. [8.2.9.1] Initiative Roll. The enemy submarine has a good chance to attack first. Roll 1d10. On a roll of 1-3, the player’s submarine has the initiative, and may either attack or avoid contact. On a roll of “4-0” the enemy submarine has detected you and attacks first, and the enemy submarine fires four torpedoes at your Submarine. This is from medium range. The

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[8.2.9.2] Player Attacking First. Sometimes the player’s submarine will attack first. To attack an enemy submarine, the player goes through the normal procedure of deciding to attack from medium/long, or risks a detection roll by going to close range. You may not attack enemy submarines with your deck gun. Notice an enemy sub is harder to hit, as it receives the “+1” warship modifier when you try to hit it with torpedoes. If you are detected while attempting to get to close range, your attack will be aborted and the enemy sub attacks you first instead from close range. If the player’s submarine has the initiative (1d10 roll of 1-3) it may also simply decline combat and the encounter ends. [8.2.9.3] Player Sinks the Enemy Sub. If the player sinks the enemy sub in the first round of combat, the encounter ends with no further action required. Only ONE point of damage is required, so any non-dud hit sinks the sub. [8.2.9.4] Player Misses the Enemy Sub. If the player misses the enemy sub, the enemy sub rolls for detection using appropriate modifiers. If detection occurs, it fires four torpedoes at the Submarine, hitting on a 2-4 at close, 2-3 at medium, or 2 at long range (2d6). Enemy submarines have duds on a roll of “1”. Any non-dud torpedo hit by an enemy sub will sink a player’s sub. At this point, assuming the enemy sub has not sunk the player’s sub, the player has the option of rolling for an additional round of combat, or to disengage. If he disengages the turn is ended and he moves to the next travel box. If he opts for an additional round of combat, he reloads, then rolls for encounters, with an aircraft or escort result meaning the enemy sub gets away (and he has to deal with the new problem). If no aircraft or escort arrives, he then starts a new round of combat against the enemy sub from scratch. [8.2.10] The Attack Mat. The Attack Mat (chart [H1]) has been provided to assist during ship and convoy combat, if desired. Its use is not mandatory, but players may find it helpful in keeping track of which torpedoes are heading toward which target, etc. [8.2.11] Combat against Escorts. Unlike the Atlantic war, combat against escorts (or just warships in general) happened with more regularity in the Pacific, for a variety of reasons. To represent this, players ARE allowed (but not required) to attack an escort that is with the target

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ship(s). To attack an escort, add a generic Escort target (2000 tons). This ship can now be added to the other available ship targets and is attacked normally per the attack rules. (Although there is more than one escort, just like there are more than 4 cargo ships in a convoy, it is assumed there will only be one in your “window of opportunity” to attack when you start). Escorts are significantly faster than cargo ships, and smaller, and get an automatic +2 drm to torpedo hit rolls against them (+1 because they are fast, and +1 because they are small, for a total of +2. This is the same drm given to DD and DE warship targets).

-If the aircraft is shot down, any second attack (if a modified “1” was rolled on chart [A4]) does NOT occur. No further actions are taken this travel box except possibly repairs. -If the aircraft is only damaged, any second attack (if a modified “1” was rolled on chart [A4) DOES occur. However, no further action is taken this travel box except possibly repairs. The aircraft, being damaged, must immediately return to base and the encounter is complete. -If the aircraft was missed completely by the AA attack, it shadows the Submarine after completing its own attack. The Submarine is considered to have dived at this point. Roll on the “Additional Round of Combat” section of the Encounter Chart [A3]. This may result in either an escort arriving which rolls for detection on chart [B4] (from medium range) or a new aircraft that arrives and attacks via chart [B5]. Notice an aircraft attack may generate another aircraft attack and so forth, if the player is extremely unlucky on the “Additional Round of Combat” rolls. Escorts must roll to detect the Submarine, but do receive the “previous detection” +1 modifier. However, new aircraft generated by “Additional Round of Combat” table go immediately to the attack chart and attack the Submarine. NOTICE: aircraft subsequent to the first one do not generate an automatic crew casualty, as the boat is considered to have already dived. After any combat is resolved, the Submarine advances one travel box on his patrol track.

[8.2.12] Sinking an Escort. If the escort is sunk, detection rolls for the rest of the combat are made at -1 (and of course you receive credit for that escort’s tonnage if sunk). If the escort survives your salvo, even if damaged, detection rolls are made at +1 for the rest of the combat. If you are using optional escort quality rules, you do not re-roll quality. If only damaged, the escort may still be attacked at a later time. Designer’s Note: Although this seems like a really good deal, players should realize that they are spending (probably) several torpedoes on a ship that has extremely small tonnage, and that several torpedoes might not even hit it, given it has a built-in +2 to hit, being a small, fast warship. Think twice before gratuitously attacking escorts. It might be better to just deal with the potential depth-charging, since if you don’t sink or damage the escort, the escorts counterattack you with an extra +1 to the detection roll.

[8.3] AIRCRAFT ENCOUNTERS [8.3.1] Roll to Crash Dive. Once an encounter with aircraft is rolled, the player rolls to see if any combat occurs on chart [A4], by rolling 2d6 and applying any appropriate modifiers. If a modified 6 or higher is rolled, there is NO combat. The aircraft was seen in time, the boat crash dives, and nothing further occurs. [8.3.2] Aircraft Attack. If a modified 5 or less is rolled, one (or possibly 2) attacks are rolled on chart [B5], with a “+2” modifier applied for an aircraft attack (for a normal attack). If the date is 5/44+ the aircraft rolls 1d6 to see if a “Special” attack occurs instead of the normal depth charge attack. On a roll of a “6” the special attack occurs, and the aircraft is assumed to have been armed with a special attack weapon (See 8.3.3 below). Damage is applied (or the Submarine is sunk outright). Also, one crew injury result is rolled for in addition to any other damage that occurred (but not for a special attack). The Submarine gets to fire AA guns. Combat is considered simultaneous, so it is possible for a Submarine to shoot down an aircraft that sinks it (which happened several times historically). Several outcomes now occur based on the AA attack on the aircraft:

[8.3.3] Aircraft Special Attacks. Similar to the escorts having a Hedgehog special attack, aircraft may also use a “special” weapon attack (in this case, a FIDO homing torpedo). A FIDO attack means the aircraft has dropped a homing torpedo. The good news is, this type of aircraft attack does not generate an automatic crew casualty. The bad news is, if the FIDO hits the Submarine and detonates, it is automatically sunk or takes 7 hits per the chart. Historical Note: Players may think the FIDO chart understates their effectiveness. It does not, as it is based on historical results. When you consider the fact that this is a first-generation homing torpedo, the results make more sense.

[8.3.4] “Hunted to Exhaustion.” If any combination of aircraft/escorts occurs 4 times with the additional round of combat cycle, you have been considered to have been “Hunted to Exhaustion.” With almost no air and no battery power remaining, you must surface and scuttle. [8.3.5] Specific AA modifiers. On many boats, there were two or more AA guns, so if at least two are still

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operational, it receives a “-1” to hit modifier. If one has been knocked out, it fires without the modifier. Obviously, if any type of Submarine has all AA guns inoperable, it cannot shoot at aircraft. Deck guns cannot fire at aircraft. For the purposes of the game, AA ammunition is unlimited. Submarines do not normally “fight it out” on the surface with aircraft...if they are unfortunate enough to have to fire their AA guns, they are considered to dive immediately thereafter. Both dual and triple 25mm mounts count as a single system (gun) for the purposes of Chart [A2].

[8.4] “FOLLOWING” A CONVOY OR SHIP [8.4.1] General. After all combat is complete in a round, a player advances his Submarine marker one travel box in the appropriate patrol track. However, if he wishes to continue to attack an escorted ship or convoy, he may stay in the same travel box and attempt to “follow”. [8.4.2] Following Damaged Ships. If any escorted ships were damaged previously but not sunk, the “following” is automatic. If escorted, they are still considered escorted on a 1d6 roll of 1-4, and normal combat rules apply, with previous damage on the ship retained. On a roll of 5-6 the ship is now an unescorted “straggler.” If you were following two ships (or possibly more) and you roll a 5 or 6, they are unescorted but “scatter” and you must choose which ship to go after. If you “follow” a damaged escort (and possibly another ship) it becomes, essentially, just another target. It is itself still escorted on a 1d6 roll of 1-5, just like any other damaged ship. If it is NOT escorted, you may attack it with impunity, but not with a deck gun. You would have to use torpedoes while submerged. If a Capital ship was damaged, following is NOT automatic, as they were quite fast compared to a submarine. In the game, it depends on the amount of damage inflicted, as it is assumed that more damage will slow the ship to the point where you can catch it. Roll 1d6. A modified roll of “1” means you have successfully followed the Capital ship. This die roll is modified by “-1” for each point of damage on the Capital ship and by -1 for having an operational radar. Example: a player attacks a Capital ship but only manages to inflict 2 points of damage. He wishes to follow the Capital ship and attack it again. His die roll to follow is -2 for the damage, meaning he follows on a roll of 1-3. [8.4.3] “Stragglers.” If any ship(s) were part of a convoy and damaged per (8.4.2) above, they “stay together” if escorted (1d6 roll of 1-5) but become separate stragglers if unescorted (1d6 roll of 6). If they separate, the player must choose which one he wishes to “finish off.” If they are together but still escorted, the player can attack any or

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all of them per a normal encounter, except that they are already damaged. In any case, if the player chooses to attack previously damaged ship(s), he loses contact with the original convoy and may NOT follow it again. The implication here is, it may be profitable, depending on the situation of the boat, to attempt to follow the convoy instead of going for the automatic “following” against a single damaged ship. [8.4.4] Following a Convoy. If a player simply wishes to continue to follow a convoy (or two ships with escort) he attempts to “follow” with a die roll. With a roll of 1-4 he is successful, and he may attack this convoy as if he had rolled a convoy on the Encounter Chart [A3]. A roll of 5-6 means the convoy or ships have slipped away, and the round has ended. Advance the Submarine marker one travel box and continue the patrol. (NOTE: A convoy in the hand is worth two in the bush, so to speak. It is almost always advantageous to try and follow a convoy unless you strongly desire some other type of encounter. Since convoys are automatically escorted, having a highly damaged Submarine may influence this decision). Having an operational radar gives the “following” die roll a -1 drm. [8.4.5] Multiple Attempts to Follow. A convoy or escorted ship(s) may be “followed” up to 2 times (for a total of 3 attack rounds) during the same travel box. If a player wishes to follow the convoy or ship again, he advances his Submarine marker one travel box and attempts to follow via the normal procedure, instead of rolling for an encounter normally for that travel box. If unsuccessful, there are no other encounters for that travel box. You cannot follow into a transit box, as you need to head to port at that time due to fuel limits.

[8.5] SUBMARINE DAMAGE [8.5.1] General. Submarines will receive nonlethal damage during the course of operations that may possibly be repaired at sea. Additionally, damage has combat effects as listed on chart [B7]. Further explanations of the effects are listed below. [8.5.2] Repair after Combat. At the end of a round of combat (NOT a combat turn), the Submarine crew under the direction of the Engineer can attempt to repair any damage the Submarine has received. Remove all “DMG” markers from fixed equipment/systems. Flip all “DMG” markers to their “INOP” sides for any item that failed the repair roll. If the Engineer is an Expert all rolls are made at “-1”. If the Engineer is dead or seriously wounded, all repair rolls are made at “+1” instead. [8.5.3] Flooding. During combat, at the end of each turn, the Submarine must check for additional flooding ONLY if it had received one

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or more flooding damage boxes that turn. It does not have to check, for example, if flooding had occurred 3 combat turns previously. On a roll of 5-6 an additional flooding damage point is taken. If the Engineer an Expert all rolls are made at “-1”. If the Engineer is dead or seriously wounded, all additional flooding rolls are made at “+1”. If ALL flooding boxes are full, the Submarine must blow ballast, immediately surface, and roll for scuttling. Unlike other damage, all partial flooding is completely removed without having to roll after combat is complete, assuming the Submarine survives. It is assumed to be pumped out eventually.

[8.5.5] Hull. Hull damage is non-repairable at sea. If the boat has every hull damage box with a damage marker on it, it is considered sunk with a loss of all hands. Upon return to base, every three hull damage markers (or fraction thereof) adds one month of refit time before the next patrol can be started. This is in addition to any normal refit time. [8.5.6] Fuel Tanks. If the fuel tanks are damaged and fail the repair roll, the boat must immediately abort at the end of combat. There are also significant combat penalties as the boat is easier to detect. Note: Having INOP Fuel Tanks does not mean they do not function or are empty. Rather, it means the leak could not be repaired and will continue to leak for the rest of the patrol. [8.5.7] Batteries. Having damaged batteries has negative effects on chart [B5]. Note: Having INOP Batteries means they have suffered significant damage that cannot be repaired and will not operate at full capability for the rest of the patrol. It does not mean they are completely dead and non-functional. [8.5.8] Radar. Having an operational radar set gives benefits to switching day/night, following, and encounter rolls. If it is inoperative these benefits are lost.

Three results may happen from crew injury: Light Wound (LW), Serious Wound (SW), and Killed in Action (KIA). If SW or KIA, the crewman cannot perform duties, with the following results:

[8.5.4] Engines. The electric motors are used while submerged; the diesels are for surface running. If one diesel is inoperative, the Submarine must abort and rolls twice for encounters per travel box en route home. If BOTH diesels are inoperative, the boat is towed home if within one travel box of base, otherwise, it is scuttled and the crew rolls for rescue. The loss of electric motors has serious combat effects per charts [B5] and [H1].

[8.5.9] Crew Injury. Japanese Submarine crews ran roughly 100 men, plus or minus based on the type of boat. the game tracks five named crewmen, pilots if present, the midget submarine crew if present, and also generic crew markers.

CAPTAIN: The Executive Officer (Exec) must take over the boat. Torpedo/Gun rolls to hit are at +1, and escort detection rolls are at +1. Additionally, if Seriously Wounded, he must stay in base for 1d6 months while he recuperates. This time is concurrent with boat refit. EXEC: No effect, unless he was in charge. If so, the Navigator (NAV) takes over the boat. Torpedo/Gun rolls to hit are at +2, and escort detection rolls are at +2. NAV: No effect, unless he was in charge. In that case, the Engineer takes over the boat and the boat must immediately abort to base. MEDIC: If incapacitated, all SW crewmen have a chance to become KIA. Roll 1d6 at the start of each travel box: 1-3 survives 4-6 dies of wounds. If the medic is NOT incapacitated, then no survival rolls are needed for SW crew. ENGINEER: Repair rolls are made at +1, to include additional flooding rolls during combat. CREW: No effect. However, if ALL generic “crewman” boxes are SW or KIA, then the aircraft encounter rolls on chart A1 are made at -1. This represents the additional difficulty the boat would have in diving while operating shorthanded. Unwounded crewmen receive wounds before second wounds are applied to previously wounded crew, and LW receive second wounds first before SW crewmen. PILOT: The Pilot(s) operate aircraft that are carried on the submarine. If SW or KIA they cannot operate the aircraft. Multiple wounds are treated per chart [B7]. However, a LW has no effect on a crew member who is already SW. [8.5.9.1] Injury Duration. Roll 1d6 for the months of recuperation for any SW crewman once you return to base. If this is LONGER than the current refit required for the boat, that crewman is replaced (and you lose any special benefits he might have had). If ALL “generic”

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crewmen are replaced after a single patrol, via lengthy wounds or KIA, the crew quality decreases by one level (to a minimum of “trained”). If the Captain is incapacitated, and it is longer than the refit period, his submarine is given to a different captain and he will receive a new submarine of his choice when released from the hospital. Notice this means any skills his old crew had earned are lost (as far as the player is concerned). He will get to roll on the [F1] Submarine School chart for his new XO and Engineer, however. [8.5.9.2] Submerged Crew Injury. If depth charge damage causes a crew injury, it is automatically a Light Wound. Simply roll for who it affects. However, they still accumulate, and can eventually lead to Serious Wounds (SW). [8.5.9.3] Expert Medic Effects. If your Medic is an Expert you may roll for each LW crew injury after an encounter. A 1d6 roll of “1-3” removes the LW. Additionally, an Expert medic reduces the recuperation time of SW crew-members by 1 month, representing lessening of recovery time due to care received while traveling back to base.

[8.5.11.3] Variable Patrol Length and “P” Months. Different classes of Japanese submarines had different patrol lengths, ranging from 1 to 4 months. Each Submarine Display Mat lists the patrol length of that class if longer than 1 month. For each month after the first, place a “P” in the month line of the Patrol Log Sheet upon return to base (“P” standing for patrol) before putting any “R” months (for refit). This is because they had longer patrols, and the “P” represents they are still out at sea for that month. For example, if September was the start of a Type A class patrol (which is 2 months long) then October would have a “P” written in it (as the boat is still on patrol) and November would have an “R” for refit. The boat would then go back out in December, assuming it suffered no damage.

[8.6] PATROL ABORT [8.6.1] General. In some cases damage will require a Submarine to abort back to base. (INOP Fuel Tanks or one Diesel Engine out). A boat can always abort at the Captain’s command. (This can be due to whatever reason he desires, although this is normally significant damage or lack of torpedoes).

[8.5.10] Multiple Damage Results. If the chart calls for damage to a system that is already damaged (or is not present, such as a hangar hit on a Type C class) treat as “no effect”. The only boat damage that “accumulates” are flooding and hull damage results. (and, as an exception, battery hits on a Sen-Taka class). Notice a second result of “AA Gun” will damage the second AA gun if two are present.

[8.5.11] Refit Rules. Submarines always have a minimum refit time of one month, meaning, if a boat with a 1-month patrol goes out in 7/43 and suffers no damage, then 8/43 is a refit month, and the boat’s next patrol occurs on 9/43. Several situations will lengthen this refit process: [8.5.11.1] Extra Refit due to Damage. Any type of damage other than hull damage that has not been repaired upon return to base is repaired “for free” up to 2 systems. If 3 or more systems (boxes) are INOP upon return, this adds one month. This extra refit time does not exceed one month - any number of damaged systems above 2 still adds just one extra month. Crew injuries are not counted for this rule. [8.5.11.2] Extra Refit due to Hull Damage. For every 3 hull damage boxes, or fraction thereof, one month is added to the refit time. So, for example, a Submarine returns to base with a damaged periscope, fuel tanks, dive planes, and 5 hull damage boxes. It will refit for 4 months....one base month, plus one for damaged systems (because it exceeded 2 systems), plus 2 more months for hull damage.

[8.6.2] Abort Procedure. To abort, the Submarine jumps to the transit box nearest its base at the end of combat and rolls for encounters normally. This may require the boat to move “backwards” on the track. If the boat has one diesel engine out, it must roll twice per travel box for encounters. Boats that are aborting are not allowed to initiate combat, although they may be attacked if detected by ships or aircraft. The boat continues until it reaches base or is sunk. If a class with 2-month patrols aborts before the halfway point of the patrol, it does not write a “P” in the patrol log (it was only out for a month or some fraction thereof). Use the same procedure for boats with 3 and 4-month patrols – calculate how long they were actually at sea to the nearest month and round down. [8.6.3] Scuttling. In some situations, a crew may be required to scuttle their boat. If all flooding boxes had flooding markers on them, the crew must immediately surface and attempt to scuttle with 2d6 roll: Scuttling Table Roll 2-11 12

Result Successful. Crew captured and made POW. Failed. Submarine captured.

(+1 to roll if Captain is SW or KIA). A Submarine with both diesel engines inoperative must also scuttle if more than one zone out to sea, but this is automatic if out of combat. Roll 2d6 for crew rescue:

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Crew Rescue Table Roll Result 2-10 Successful. Rescued 11-12 Failed. Lost at sea

Keen Judgement (Engineer)

The first time, each patrol, a captain performs an “Exceeding Test Depth” check, there is no hull damage. Torpedo The player may re-roll a torpedo miss Gunnery (Capt) on Chart B1 once per patrol. Midget Torpedo Midget submarine may re-roll a Gunnery torpedo miss on Chart B1 once per mission. Superior Comms Midget submarine recovery receives a +1 drm on Chart M7. Boat Handling Midget submarine crossing a net coverts result “4” into “through net.” Aerial Navigation Aircraft receive a +1 drm on recovery after flight. Aircraft Maint. Once per mission may re-roll a mishap/ malfuncction on Chart K2. A.C.M. (Pilot) Air Combat Maneuvering. The first damage result per combat (only) is reduced by 1. Weapons Expert Bombing rolls receive +1 drm and (Aircraft) rear machine gun defensive fire receives -1 drm. Crew Overall Crew skill increases one level*

(+4 to roll if Radio is inoperative).

[8.7] CREW SKILLS AND ADVANCEMENT [8.7.1] Procedure. The various crew members, including the Captain, may increase in skill during the course of the war. The overall crew level may also be increased. For every 3 successful war patrols, choose once on the table below. (A successful patrol is defined by a patrol in which the boat returned to base, at LEAST one ship was sunk, OR a special mission was successfully performed). Place a marker on the specific crew position on the Submarine. Skill Effects Crew Expert Engineer Mech. Genius (Engineer) Expert Medic

Expert XO

Effect All repair rolls at -1 May repair one system that has failed its repair roll and is currently INOP. May only be used once per patro. Rolls once to reduce LW status; successful on 1d6 1-3. Also gives -1 to Serious Wound die roll for months of incapacitation. No penalty if takes command; -1 drm on Surface torpedo “to hit” rolls. +1 on Chart [A4] Aircraft Encounters -1 on “to hit” rolls with Deck Gun on Chart [B1] -1 on the [A2] AA Chart

Vigilant (XO) Deck Gun Expert (XO) AA Gun Expert (XO) Expert Navigator “Run Aground” random event negated. Boat not required to abort if the Navigator is in-command. Boat gets 1 extra travel box if desired per patrol - roll again in any travel (not transit) box for encounters. Shibumi (Capt.) Difficult to translate - may be thought of as “effortless perfection.” The Captain may, once per patrol, succeed in a die roll check without rollilng. May be for torpedo “to hit” roll, torpedo dud check, crash-diving, from aircraft on Chart A4, and for an exceeding test depth check. Leadership Promotion attempts automatically (Captain) succeed.

* Crew Skill levels are Green, Trained, Veteran, and Elite. [8.7.2] Crew Levels. The Submarine crew starts at a training level of “Trained”. If chosen, the crew level increases to “Veteran”. Veteran crews fire AA at -1 effectiveness against aircraft on Chart [A2]. Veteran crews may increase to “Elite” crews. Elite crews fire AA at -1 on Chart [A2] and ALSO add +1 to crash dive aircraft encounter rolls on chart A4. Crews may not advance above “Elite” status or fall below “Green” status. “Green” crews are +1 to hit with all weapons, and get -1 on chart A4 aircraft encounter rolls. [8.7.3] Crew Level Decrease. If all generic crew markers receive SW or are KIA during a patrol, the crew training level DECREASES one level (if currently higher than trained). If a Submarine has 3 unsuccessful patrols in a row, the crew level decreases by one (possibly down to green). [8.7.4] Expert Executive Officer Promotion. At the end of each patrol, roll 2d6 if the Exec is an Expert. A roll of 2-3 indicates he has been given his own Submarine and must be replaced with a new Exec. (It didn’t take long for experienced Submarine officers to receive their own boat).

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[8.8] AWARDS

[8.9] PROMOTIONS

The game includes a series of awards that were available to Japanese submarine commanders in World War II. Except for the Order of the Golden Kite, the awards have no game play impact and are included for historical interest.

The Captain of the Submarine was the “Captain,” however, his rank varied. At higher ranks, the Captains have more influence with the Submarine command, and this has various positive impacts on game play. [8.9.1] Ranks. The ranks and associated abilities are:

[8.8.1] The Order of the Golden Kite, 4th Class. This highly coveted award was given to successful submarine captains for valor in the line of duty (the 4th Class may be roughly considered to be equal to the American Navy Cross). In the game, it is awarded to captains for having sunk a capital ship or after a patrol in which their tonnage exceeds 50,000 tons. Players who possess the Order of the Golden Kite receive a “-1” to all detection rolls. (does not stack with the 5th Class award). This award is only given to captains of field grade rank (Commander and Captain). If the player already has the order of the Golden Kite, 5th Class, from when he was a Lieutenant-commander, the award criteria for the 4th Class award becomes 100,000 tons or a capital ship.

1. Lieutenant-commander The player’s lowest possible starting rank. No special abilities. 2. Commander

[8.8.2] The Order of the Golden Kite, 5th Class. This award was given to successful submarine captains for valor in the line of duty (the 5th Class may be roughly considered to be equal to the American Silver Star). In the game, it is awarded to captains for having sunk a capital ship or after a patrol in which their tonnage exceeds 50,000 tons. Players who possess the Order of the Golden Kite receive a “-1” to all detection rolls (does not stack with the 4th Class award). This award is only given to captains of junior officer rank (Lieutenant-commander). [8.8.3] The Order of the Rising Sun, 8th Class. This was an award for meritorious service. Players receive it after their second year of service. (24 months in the game). [8.8.4] The Order of the Sacred Treasure, 8th Class. This is another service award. Players receive it after 12 months of service. [8.8.5] The Wound Badge. This is awarded to a player after having been wounded on patrol. It may be received posthumously.

Allows the player to request a specific patrol assignment on a 1d6 roll of a ‘1’. If this occurs, the player may choose his next patrol area from the currently active list on chart A1. If his roll fails (on a roll of 2-6), he simply now rolls normally for a random patrol assignment. Notice this is voluntary; the player is not required to try and pick a specific patrol assignment. 3. Captain Allows the player to request a specific patrol assignment on a 1d6 roll of a 1-2, using the same procedure as above. Also allows the player to shorten any repair times in between patrols by one month, if the repair time is scheduled to be 3 months or longer (no effect on a repair of 1 or 2 months). This represents his greater influence and ability to manipulate the system to get faster repairs. [8.9.2] Promotion mechanics. Each promotion attempt is made after the 12th month of service, and every 12 months after that. For example, a player who started in 12/41 would first roll for promotion in 12/42, then each December after that. Failing a promotion roll simply means the player remains at his current rank, and must wait till the next period for reconsideration. Each successful promotion grants the player a Submarine Upgrade marker (see 9.3). Promotion to the next higher rank occurs on a successful 1d6 roll of 1-4, with the following modifiers: -1 Per award of the Order of the Golden Kite (either Class) during the period.

[8.8.6] The Greater East Asia War Medal. This is awarded after a player’s first patrol (successful or not). [8.8.7] The Submarine Badge. This is awarded to a player after graduating from Submarine School at the start of the game.

-1 Sink 5 ships during the period. +1 Each unsuccessful patrol during the period. A player may have multiple + or - modifiers depending on how the year went. For example, it’s possible a player could

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have a +3 modifier based on having had 3 bad patrols that year. Promotion in that case would be fairly unlikely.

A boats) and continue until both sunk or until reaching a pre-agreed upon ending date. The player with the most tonnage sunk wins. The players alternate patrols, with one player running his Submarine and the other player rolling for the escort detection, attacks, damage, and also air attacks. If optional rules are used, the current Submarine player will decide which evasive maneuver to use, and the escort player will pick choose a direction before both are revealed.

Captains with the “Leadership” skill do not roll for promotion. They are automatically promoted each attempt. [8.9.3] Starting rank. Players start the game as a Lieutenant-commander.

[8.9.4] Rank requirements for upgrade. A player must have a rank of “Commander” or higher to be able to request a Type A (Modified) or a Sen-Toku Class for a submarine upgrade.

[10.2] TOP TONNAGE TOURNAMENTS

All players start at an agreed upon date, with the same type boat, and run war patrols until killed or until the end of July 1945. The player with the most tonnage wins (dead or alive).

9.0 Reassignment to a Newer Boat

[10.3] SURVIVAL TOURNAMENTS

A player may be reassigned to a newer model submarine under certain circumstances:

[9.1] REASSIGNMENT DUE TO HOSPITAL STAY If seriously wounded and requiring 5-6 months to heal, the player is automatically given a new boat (and new crew which starts at “trained” status with no special abilities for the other crew-members) of the same type which he started on. He may choose any type of boat currently available at that time and goes back out to sea 1 month after release from the hospital.

This uses the same format as the top tonnage tournaments, EXCEPT the player is required to survive to the end of 7/1945.

[10.4] MIXED BOAT TOURNAMENTS This uses the same format as any of the above tournaments, EXCEPT the requirement to have all players use the same boat is lifted, i.e., players are free to choose any class available at their personal whim.

[9.2] REASSIGNMENT DUE TO REFIT If his current Submarine returns and has a 5 month or longer refit, the player automatically receives a new boat of the same type (and latest model, in the case of the Junsen and Kaidai classes). In this case he gets to keep the same crew with all abilities they may have, and goes out to sea after one month “refit” instead of the 5+ months.

[9.3] UPGRADE DUE TO UPGRADE MARKERS At the end of the patrol in which a Captain receives the Order of the Golden Kite (4th or 5th Class) he receives an Upgrade marker, which he may use to request a newer model boat, if a newer type is available, or to switch to a different class. He may save any/all of these upgrade markers for a later month if he wishes (for example, a newer model of Submarine that is desired may not yet be available). In such a case, the Captain gets to retain his previous crew, and goes out to sea in the new boat 1 month after having received it.

10.0 Multi-Player/Tournament Rules [10.1] TWO PLAYER GAME Both players should start with the same boat at the same month (for example, both could start at 12/41 with Type

11.0 Optional Rules [11.1] STANDARD TONNAGE AMOUNTS If players wish, they may use a standard tonnage amount instead of rolling for ships randomly. This should speed up play by reducing dice rolls, at the expense of some variability and historical interest. They are: Small Freighter

Large Freighter

3,500t 7,000t

Tanker 9,000t

Capital and other ship encounters should still be rolled for.

[11.2] INCREASED HISTORICAL TARGETING Players who wish to add more historical flavor to their game at the expense of additional record-keeping should consider writing the name of their targets below the tonnage on the patrol log. If any of those ships are sunk, then rolled for again as a target anytime later in the captain’s career, roll again until the target is not a previously sunk ship. Therefore, you will never sink the same ship twice in a career. This is not normally an issue for casual play as it rarely occurred in testing during the course of a single career (although it did happen sometimes).

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this, players may use this rule if they wish. After an attack on an escorted ship (or ships) but before rolling for detection, check for escort quality by rolling 1d6:

[11.3] EVASIVE MANEUVERS At the cost of adding time to the combat cycle, players may use this optional rule to give them some additional variation in trying to evade depth-charges. Before each combat dice roll (assuming detection has occurred) the Submarine commander picks a number from 1-6 which is his evasive direction (Left, Right, Straight).

Year ‘41-’42 ‘43-’44 ‘45

1,2 = Evade Left 3,4 = Evade Right 5,6 = Evade Straight The player then rolls one die: If the escort direction is different than the Submarine’s evasive direction, the Submarine takes one less Hit on the Attack Chart (B5) when the attack is rolled. If the escort direction matches the Submarine’s direction but the number is not exactly equal to it, the Submarine takes one additional Hit on the Attack Chart (on top of however many hits were rolled for - for example, if a “12” were rolled, the Submarine would take 6 hits, not just 5).

[11.5] VARIABLE AIRCRAFT QUALITY

There were significant differences in the quality of the Allied aircrews hunting the Submarines. Some were very skilled while others just didn’t drop their depth charges or bombs very accurately. Additionally, different aircraft had different weapons available. To represent these factors, players may use this rule if they wish. After failing to crash dive in time, but before rolling the aircraft attack, check for aircraft quality by rolling 1d6:

If the escort number is EXACTLY equal to the Submarine’s chosen evasive number, the Submarine takes 3 additional hits. EXAMPLE: The submarine player chooses the number “six” which means he is evading straight. Here are the possible results when he rolls a die for the escort direction:

Year

1 = wrong direction, one less Hit

‘41-’42 ‘43-’44 ‘45

2 = wrong direction, one less Hit 3 = wrong direction, one less Hit 4 = wrong direction, one less Hit

6 = right direction, exact match, three additional Hits on chart B5. In a two-player game, both players secretly choose direction by secretly placing their chosen number face up on a die then revealing them simultaneously. Evasive maneuvers cannot be used if the submarine has hydrophone damage.

[11.4] VARIABLE ESCORT QUALITY

Even early in the war, there were significant differences in the quality of the escort commanders. Some were extremely timid (and, to be blunt, inept) while others were extremely aggressive, determined, and persistent in their attacks and tactics. Additionally, there were significant differences in the quality of the equipment (ships, radars, sonars, etc) itself. To represent

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Elite 6 6

Green escorts do one less Hit than whatever is rolled for on chart B5. Trained escorts use the charts normally. Veteran escorts do +1 Hit on top of however many hits are rolled for when they use Chart B5. Elite escorts are +1 to detect in addition to doing +1 Hit on chart B5.

1,2 = Escort Left 3,4 = Escort Right 5,6 = Escort Straight

5 = right direction, but not exact match, one additional Hit on chart B5.

Quality Green Trained Veteran 1 2-5 6 1 2-4 5 1 2-3 4-5

Elite 6 6

Green aircraft do one less Hit than whatever is rolled for on chart B5. Trained aircraft use the charts normally. Veteran aircraft do +1 Hit on top of however many hits are rolled for when they use Chart B5. Elite aircraft cause 2 crew casualties automatically (instead of one automatic) in addition to doing +1 Hit on chart B5.

[11.6] HISTORICAL SUBMARINE I.D.

For those players who wish an “historical” number to assign to their boat, the following is a list of those submarines by number that fell within the major subtypes as presented in the game:

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Historical Submarine I.D. Type IDs In Service Junsen J. 1M I. 5 Junsen J. 2 I. 6 Junsen J. 3 I. 7, I. 8 KD. 3 I. 53 (later I. 153); I. 55 (later I. 155); I. 54 (later I. 154); I. 58 (later I. 158); I. 56 (later I. 156); I. 57 (later I. 157); I. 59 (later I. 159); I. 60; I. 63 KD. 4 I. 61; I. 62 (later I. 162); I. 64 KD. 5 I. 65 (later I. 165); I. 66 (later I. 166); I. 67 KD. 6 I. 68 (later I. 168); I. 69 (later I. 169); I. 70; I. 71 (later I. 171); I. 71 (later I. 171); I. 72 (later I. 172); I. 73 I. 76 through I. 85 (later I. 176 to I. 185) KD. 7 Type A I. 9 through I. 12 Type A (Mod) I. 13; I. 14 Type B I. 15; I. 26; I. 30; I. 17; I. 23; I. 29; I. 31; I. 36; I. 19; I. 28; I. 33; I. 35; I. 21; I. 27; I. 32; I. 34; I. 38; I. 39; I. 40 through I. 45 Type B. 3 I. 54; I. 56; I. 58 Type C I. 16; I. 22; I. 18; I. 24; I. 20; I. 46; I. 48 Type C. 3 I. 52; I. 53; I. 55 Sen-Toku I. 400; I. 401; I. 402 Sen-Taka I. 201 through I. 204

5. Carrier killer - extra “-1” to hit against CV and CVE targets.

[11.7] OPTIONAL SPECIAL ABILITIES

14. Deck gun expert - deck gun to hit rolls have a “-1” drm. (XO gets this skill)

6. Aggressive - must always attack any ship contacts if possible. Must always initiate an additional round of combat against nonsunk, unescorted targets. 7. Bold - may move to close range with a detection roll of “12.” 8. Skilled - may fire fore and aft torpedoes without a “to hit” penalty. 9. Vigilant - extra “+1” drm to crash dive rolls. (XO gets the skill) 10. AA expert - fires AA with an extra “-1” drm. 11. Leadership - rolls for upgrades after every second successful patrol, instead of after the third. 12. Tanker killer - extra “-1” to hit against tanker targets. 13. Convoy killer - extra “-1” to hit against convoy targets.

Players may wish to try this rule just for fun, however, most abilities listed will grant the player an advantage and make the game easier. This rule gives each Captain (sometimes the XO) an ability to start the game. Notice that some are also skills that can be earned per (8.7). Roll 1d20 at the start of each career (or choose your favorite): 1. Lucky - starts the game with a “Maneki Neko” counter. 2. Tracker - does not have to roll to maintain contact with ships or convoys. 3. Capital ship killer - extra “-1” to hit against capital ships. 4. Teamwork - crew starts at “Veteran.”

15. Straggler killer - when “convoy” is rolled for an encounter, may roll for a single unescorted target instead (once per patrol). 16. Political - may choose own patrol zone on a roll of 1-3. 17. Midget Submarine Expert – Midget commander automatically has all skills from midget sub school. 18. Scrounger - may choose the types and numbers of torpedoes loaded at patrol start from any currently available.

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19. Keen Judgment - does not take a hull damage the first time (only) each patrol when exceeding test depth.

Now Bob switches to Map M1 for his Midget submarine operation. On a patrol without a special mission, he would roll for an encounter, but since he’s on a special mission, that IS his encounter for the first “On Station” box. He places his Midget Sub mat in front of him, with the two torpedoes loaded and ready, and then places the marker on Map M1 in the first Transit Circle, and rolls on Chart [M5] for an encounter. There is none, so now he must pass through the Torpedo & Boat Net as shown on the map.

20. Charismatic - all replacement named crewmen arrive as “Expert.” Good luck!

[11.8] OPTIONAL NAME GENERATOR Chart [H2], Japanese Sub Commander Names, will assist players who wish to generate a random Japanese name for their boat’s captain.

12.0 Example of Play Bob decides to play a Type C Class submarine, as it is available at the very start of the war. Per rule [4.5] procedure #4, he rolls a 1d6 2, which means he must load 12 x Type 89 steam torpedoes, with the rest being Type 95 Oxygen. He loads the better Type 95 torpedoes forward and aft, with all 12 reloads being the Type 89 steam. He places the Yokosuka port marker on his sub mat, as all Dec 41 submarines start there, and places 5 deck gun ammo on the mat, along with the Midget sub with its two torpedoes. Bob then attends the Kure submarine school (Chart [F1]). Although he, his XO, and his engineer don’t earn any skills, he spends his spare time in meditation (Gosei) and receives the good luck charm (Maneki Neko) which is placed on his submarine mat. Since he has a Midget Sub, that commander attends the Midget Submarine School (Chart [F2]). More bad luck, as the only skill earned is Superior Comms. Place that marker on Chart [K1].

Now Bob places the four starting Major Event Markers on the Operations Map. He now rolls on Chart [A1] to find his patrol assignment. He’s in luck finally, as a result of “8” means he’s been assigned to the attack on Pearl Harbor. Flipping the Pearl Harbor Major Event marker to the back side, he sees “Midget 1 / Recon 7 / Patrol” as the Special Missions. Since he does have a midget sub, he’ll perform the first special mission listed, which is Midget 1 (meaning Map M1 is used.) He now sails from Yokosuka, moving his sub marker from the “At Port” box to the first Transit box. Per the note at the bottom of Chart [A3], there will be no normal encounters in transit boxes until 7/42, but he still rolls for them just in case he gets a “12” which would be a random event. But he rolls an “8” so now he proceeds on the patrol. At this point, Bob sees he has five “On station” travel boxes, however, since there are two “extra” transit boxes when heading to Pearl Harbor, he really only has 3 boxes that are “On station.” In essence, the two extra transit boxes shown on the Operations Map for a Pearl Harbor Patrol reduce his available On Station patrol time. Nothing occurs in the second Transit Box, so he has arrived at the first “On Station” box, where the Special Mission is executed.

He rolls a “5” and barely makes it through the net, and is on to the next Transit Circle. Unfortunately, here he rolls a “10” which is a Midget Sub Event (similar to Random Events but more than one can occur.) A roll of “4” on Chart [M6] means he has broached, but rolls a “6” which means they regain control and get back beneath the surface. On to Transit Circle #3, where a roll of “7” gives another Event. Here, his luck runs out, and a roll of “2” means the midget is lost and never heard from again, because Bob unluckily rolls two more hull damage besides the first one. Bob skips the Midget Sub Recovery routine as that cannot now occur. The first “On Station” box has concluded. For the second box, he rolls a “5” on the Pearl Haror section of Chart [A3] which would be a reroll if he had radar, but he does not. So it is “no encounter”. In his third and final “On Station” box, he rolls a “7” which is a ship plus escort. A roll of “3” per the note at the bottom of the chart indicates this is a small ship, so he consults Chart [T1] and rolls a “77’ which is the Nancy Moller, at 3,900 tons. A roll of “2’ for the Day/ Night check (rule 8.1.9) means it is day. After the failure of his midget sub, Bob decides he wants some revenge, so he fires all four forward torpedoes from medium range at the ship. He is submerged, and with Type 95 torpedoes, there are no modifiers, so 2-7 will be a hit. He gets 2 hits out of the four fired, which is a good thing, as checking Chart [B2] he finds one is a dud. The freighter takes two points of damage to sink, but the lone Type 95 that detonates does 3 points with a roll of “2” on Chart [B3] so the Nancy Moller is sunk. Bob notes this on his logsheet. Now, the escort comes looking for him, but the Type 95 torpedoes are oxygen driven (not steam) so there are no negative modifiers on Chart [B4]. A roll of “6” means he is undetected and gets away. The final two transit boxes are uneventful, and Bob returns safely to Yokosuka. He receives the Greater East Asia War Medal (per [8.8.6]). The mission was not considered successful per [7.3] so he gains no credit for the purposes of skill purchase and/or crew advancement. The Type C Class performs two-month patrols, so it was out Dec 41 and Jan 42, with Feb 42 being the Refit month. His boat would go out on its second patrol in March 42, as it sustained no damage. The lost midget submarine would be replaced.

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Designer’s Notes Making “Sensuikan” was in response to the many requests I received from players who wanted to experience the Pacific submarine war from the Japanese side. As usual, easier said than done. One of the main issues was that the normal “Hunters” game system was not applicable without major modifications. The Japanese viewed their submarine force quite differently than other nations – they were expected to be part of the “decisive battle” against enemy fleets, and not really seen as doing what submarines do best – interdiction of lines of communications and the destruction of merchant shipping. To replicate this, I came up with a system of special missions tied into the major events of the war. Instead of patrolling freely looking for shipping, many times the Japanese player will be forced into watching a picket line, or delivering supplies, or conducting reconnaissance. Players will get a sense, I hope, of the issues and limitations placed on Japanese submarine commanders by their Navy. Another design issue was the crazy submarine designs the Japanese had – perhaps a better word would be “innovative.” Submarines with aircraft in watertight hangars on the deck, submarines that carried midget submarines, and kaiten “suicide torpedoes.” Brett Grimmond, a friend from Australia, begged me to include extremely detailed “mini-games” for these 3 areas. We finally compromised on “modules” that allow the player to “zoom in” on the action when it came to midget submarines, aircraft, and kaiten. It adds a bit of complexity to the game, but these modules only apply if your particular class has that capability, so it’s not overwhelming. In fact, you can play an entire game without utilizing any of the modules, so I felt this added complexity really wasn’t bad, considering it is only used on occasion. The modules do add extensive depth to the game, however, and would not have occurred with Brett Grimmond’s hard work and concept, and for that I owe him a debt of gratitude. There were multiple reasons for the lackluster Japanese submarine performance (historically). They had superb torpedoes and adequate fire control systems, but they suffered from a lack of radar for most of the war. Additionally, although (for the most part) Japanese submarines were very long-ranged, they were slow divers, noisy, and suffered from poor underwater maneuverability. Technical issues aside, probably the biggest hindrance to their effective use was the Japanese high command’s doctrine on HOW they should be used. Mainly they were viewed as a force multiplier for the surface fleet, and not as a force to be used to cripple the enemy’s merchant shipping (although they did sometimes do that). Combined

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with the superb American ASW capability as the war progressed, it is no wonder they underperformed and suffered such horrific losses in 1943 and beyond. -Greg Smith

Selected Bibliography Bagnasco, Erminio. “Submarines of World War Two” Cassel and Co, 2000. Superb all-around reference for the submarines of the major nations, with operational and doctrinal commentary. Highly recommended. Boyd, Carl and Yoshida, Akihiko. “The Japanese Submarine Force and World War II” Naval Institute Press, 1995. Costello, John. “The Pacific War” Atlantic Communications, Inc., 1981. Another overall historical account of the entire war, but a bit more detailed operationally than others. Recommended. Hashimoto, Mochitsura. “Sunk: The Story of the Japanese Submarine Fleet 1941-1945” Henry Holt & Co, 1954. Decent account from the Japanese perspective. Has several useful appendices. Jordan, Roger. “The World’s Merchant Fleets 1939: The Particulars and Wartime Fates of 6,000 Ships” Naval Institute Press, 1999. Where -did- all those target listings come from? :) Not exactly light reading, but a good reference. Orita, Zenji. “I-Boat Captain” Major Books, 1976. Solid first-person account from a Japanese submarine commander. A bit biased, but understandable. Rohwer, Jürgen. “Axis Submarine Successes of World War Two” Greenhill Books, 1999. Although most of the listings are for German U-Boats, the Japanese listings were invaluable. Spector, Ronald. “Eagle Against the Sun.” The Free Press, 1984. Big picture historical account of the entire Pacific War. Stille, Mark. “Imperial Japanese Navy Submarines 1941-45” Osprey Publishing, 2007. A typical Osprey offering, with excellent illustrations and some technical details.

Credits: Game Design: Gregory M. Smith and Brett Grimmond Playtesting: Brett Grimmond, Rich Paris, Fred Ellsesser. Lee Smith, Glenn Saunders Playtest Art: Lee Smith Artwork & Layout: Nadir Elfarra Index: John Kranz

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RULES INDEX Abort Procedure [8.6.2]............................................ 24 Additional Rounds of Combat [8.2.8]...................... 19 Aircraft Attack [8.3.2]............................................... 20 Aircraft Encounters [8.1.7, 8.3]................................ 18 Aircraft Encounters [8.3].......................................... 20 Aircraft Launch and Recovery [7.15]....................... 15 Aircraft Module, The [7.17]..................................... 16 Aircraft Module Play Sequence [7.17]..................... 16 Aircraft Special Attacks [8.3.3]................................ 21 Air Raids on Ports [4.7.6]......................................... 10 Ammo Markers [4.6].................................................. 9 Anti-Aircraft Attack Procedure [8.3.2]..................... 21 Attack Mat, The [8.2.10].......................................... 20 Attack Mat [3.2].......................................................... 5 Attack Procedure [8.2.3]........................................... 18 Aur Raids on Ports Table [4.7.6].............................. 10 Automatic Escape [8.2.7]......................................... 19 Awards [8.8].............................................................. 25 Basing [4.7]................................................................. 9 Batteries [8.5.7]........................................................ 22 Bombing Mission [7.7]............................................. 13 Capital Ship Encounters [8.1.4]................................ 17 Charts and Tables [3.4]............................................... 6 COMBAT [8.0].......................................... 17 Combat Against Escorts [8.2.11].............................. 20 Combat Rounds [8.1.1]............................................. 17 Convoy Encounters [8.1.6]....................................... 17 CREDITS ................................................ 30 Crew Injury [8.5.9]................................................... 23 Crew Level Decrease [8.7.3].................................... 25 Crew Levels [8.7.2].................................................. 25 Crew Skills and Advancement [8.7]......................... 24 Deck Gun/Aircraft Removal and Kaiten [7.12]....... 14 Deck Gun Firing [8.2.4]........................................... 18 DESIGNER NOTES................................... 29 Determining Vicory [5.2]...........................................11 Dutch East Indies (DEI) [4.7.5]................................ 10 Encounters with Ships; Attacks Against Shipping [8.2]........................................................... 18 Ending the Game [5.1]...............................................11 Engines [8.5.4].......................................................... 22 Escort Detection [8.2.5]............................................ 18 Evacuation [7.6]........................................................ 13 Evasive Maneuvers [11.3]........................................ 27 Exceeding Test Depth [8.2.6]................................... 19 Expert Executive Officer Promotion [8.7.4]............ 25

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Expert Medic Effects [8.5.9.3]................................. 23 Extra Refit due to Damage [8.5.11.1]....................... 23 Extra Refit due to Hull Damage [8.5.11.2]............... 23 Flooding [8.5.3]........................................................ 22 Following a Convey or Ship [8.4]............................ 21 Following a Convoy [8.4.4]...................................... 22 Following Damaged Ships [8.4.2]............................ 21 Fuel Tanks [8.5.6]..................................................... 22 GAME EQUIPMENT [3.0]............................. 5 Game Markers [3.3.2]................................................. 5 Game Play Outline [6.0]............................................11 Game Scale [3.6]........................................................ 7 GAME SET-UP [4.0]..................................... 7 Historical Submarine I.D. [11.6].............................. 28 HOW TO PLAY THE GAME [2.0]................... 3 How to Read the Markers [3.3.1]............................... 5 HOW TO WIN THE GAME [5.0].................. 10 Hull [8.5.5]................................................................ 22 Hunting to Exhaustion [8.3.4].................................. 21 Increased Historical Targeting [11.2]....................... 27 Initiative Roll [8.2.9.1]............................................. 19 Injury Duration [8.5.9.1]........................................... 23 INTRODUCDTION [1.0]............................... 3 Kaiten Attack [7.8].................................................... 14 Kaiten Module, The [7.18]....................................... 16 Kaiten Module Play Sequence [7.18]....................... 17 Kasumigaura Naval Air School [4.8.3].................... 10 Kure Submarine School [4.8.1]................................ 10 Major Event Markers [7.14]..................................... 14 Midget Submarine Attack [7.3]................................ 13 Midget Submarine Module, The [7.16].................... 15 Midget Submarine Play Sequence [7.16]................. 15 Midget Submarine School [4.8.2]............................ 10 Mine-Laying [7.10]................................................... 14 Mixed Boat Tournaments [10.4]............................... 27 MULTI-PLAYER/TOURNAMENT RULES [10.0]............................................ 27 Multiple Attempts to Follow [8.4.5]......................... 22 Multiple Damage Results [8.5.10]............................ 23 New Guinea [4.7.4]................................................... 10 Night Attacks [8.2.2]................................................. 18 No Encounter [8.1.2]................................................ 17 OPTIONAL RULES [11.0]........................... 27 Optional Special Abilities [11.7].............................. 28 Paramushiro [4.7.2].................................................. 10 Parts Inventory [3.7]................................................... 7

Passenger Delivery [7.11]......................................... 14 Patrol Abort [8.6]...................................................... 24 Patrol Log Sheet, The [3.5]......................................... 6 Picket Line [7.2]....................................................... 13 Player Attacking First [8.2.9.2]................................ 20 Player Misses the Enemy Sub [8.2.9.4].................... 20 Player Sinks Enemy Sub [8.2.9.3]............................ 20 Playing Pieces, The [3.3]............................................ 5 Prepare Patrol Log Sheet [4.3]................................... 7 Promotion mechanics [8.9.2].................................... 26 Promotions [8.9]....................................................... 26 Radar [8.5.8]............................................................. 23 Random Events [8.1.8]............................................. 18 Range Decision [8.2.1]............................................. 18 Rank Requirements for Upgrade [8.9.4].................. 26 Ranks [8.9.1]............................................................. 26 Reassignment due to Hospital Stay [9.1]................. 26 Reassignment due to Refit [9.2]............................... 26 REASSIGNMENT TO A NEWER BOAT [9.0].. .............................................. 26 Reconnaissance [7.1]................................................ 13 Refit Rules [8.5.11]................................................... 23 Repair after Combat [8.5.2]...................................... 22 Roll to Crash Dive [8.3.1]........................................ 20 Scuttling [8.6.3]........................................................ 24 SELECTED BIBLIOGRAPHY . . ................... 30 SEQUENCE OF PLAY [6.0].. ........................ 11 Ship Encounters [8.1.3]............................................ 17 Shore Bombardment [7.9]........................................ 14 Sinking an Escort [8.2.12]........................................ 20 Skill Effects [8.7.1]................................................... 24 Special AA Modifiers [8.3.5].................................... 21 Special Mission Completion [7.13].......................... 14 SPECIAL MISSIONS AND MAJOR EVENTS [7.0]. . .............................. 12 Special Procedure for Encounters with Enemy Submarines [8.2.9].................................................... 19 Standard Tonnage Amounts [11.1]........................... 27 Start Date [4.2]............................................................ 7 Starting Rank [8.9.3]................................................. 26 Stragglers [8.4.3]...................................................... 21 Strategic Transport (Europe) [7.5[............................ 13 Submarine Damage [8.5].......................................... 22 Submarine Display Mat [3.1]..................................... 5 Submarine Display May Setup [4.4].......................... 8 Submarine Model Selection [4.1]............................... 7

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