Ship-to-Ship Combat

When ships themselves become a part of a battle, combat becomes unusual. The following rules are not meant to accurately simulate all of the complexities of ship-to-ship combat; rather, they represent an attempt to strike a balance between verisimilitude and ease and speed of play during combat, and can be applied to a vessel of any size, from a simple dinghy to a multi-deck man-o’-war.

It is important to note that while ships can be attacked in combat, it is difficult to significantly damage such large vehicles. In addition, a captured ship is usually worth more as a prize to be towed or sailed home than sunk to the bottom of the sea. As a result, most ship-to-ship combat ends when the crew of one ship boards another to fight the enemy crew in hand-to-hand combat.

Ship Basics

The following overview presents the basic rules for ship-to-ship combat in the Skull & Shackles Adventure Path. All ships use these rules for movement and combat.

A ship requires two things to keep it moving — a pilot and a means of propulsion. A pilot is a creature with an Intelligence score of 3 or higher who is physically able to use the ship’s control device. A ship’s captain is often (but not always) the pilot. The pilot uses the control device and either her sailing skill (see the Sailing Check section on page 10) or her Wisdom to control the ship. Without a pilot, a ship will not move or will continue moving in a straight line, depending on the ship’s state when it becomes pilotless.

Most ships require a crew. A ship without a full crew complement, but with at least half its crew, takes a –10 penalty on all sailing checks. A ship needs at least half its crew complement in order to be piloted at all. If more than half of a ship’s crew is killed, dazed, stunned, or rendered unconscious, the ship can only take the “uncontrolled” action. Crew members can take no action while the ship is in motion except to aid in that ship’s movement. Any crew required to operate siege engines are in addition to those crew needed to operate the ship.

Size and Space
Ships have sizes and spaces different from creature sizes and spaces. In order to play out ship-to-ship combat on a Flip-Mat or battle mat, a single square on the map corresponds to 30 feet of distance, rather than 5 feet. Most ships are long and thin; rather than taking up a space of an equal number of squares per side like creatures do, a ship’s width is always considered to be one square.

Facing and Movement
Ships do not move like creatures, even when they use creatures for propulsion. They tend to move in the direction of their forward facing, and do so quickly. Facing: Unlike creatures, ships have a forward facing. Usually one of the shorter sides of a ship serves as the ship’s forward facing. Facing represents the effect of inertia on vehicles. Ships move best when moving in the direction of their forward facing, and it takes time and skill to move them in other directions.
When piloted correctly, ships can move straight ahead, diagonally, or a mix of both within the same movement. Skilled pilots can make a ship zigzag in a forward direction with ease.
Movement: Ships have a maximum speed and an acceleration listing. The maximum speed is the fastest rate the ship can travel per round (though a windpropelled ship sailing in the direction of the wind can double this speed). A ship cannot usually start at its maximum speed. Each round, the pilot can attempt to accelerate the ship or decelerate it by a rate equal to its acceleration. The rate at which a ship is currently moving is called its current speed.
Edge of the Map: When playing out ship-to-ship combat on a Flip-Mat or battle mat, the edge of the map forms an artificial boundary — on the open sea, there is no edge of the map. As a result, if a ship moves off the edge of the map, you should extend the map with a new blank Flip-Mat or battle mat, or reposition the ships so they have room to maneuver.
Waterborne Movement: Travel over long distances across seas or oceans uses waterborne movement, measured in miles per hour or day. For muscle-propelled ships, a day represents 10 hours of rowing. For a wind-propelled sailing ship, it represents 24 hours. Waterborne speeds for the most common ship types can be found on page 174 of the Core Rulebook or in the individual ship stat blocks beginning on page 23.

Sailing Check
To control a ship in combat, a pilot must make a sailing check to determine the maneuverability and speed of the ship that round. The ship’s propulsion determines what skill is used for the sailing check (see Propulsion and Sailing Skills on this page). If a ship is using two means of propulsion at the same time, such as wind and muscle, the pilot chooses which skill to use, and takes a –5 penalty on all sailing checks. A pilot can always make a Wisdom check in place of a sailing check. Outside of combat, the base DC for all sailing checks is DC 5. In combat, the base DC for all sailing checks is DC 20. A ship without a full crew complement, but with at least half its crew, takes a –10 penalty on all sailing checks.
Aid Another: Just as with other skills, a character can spend a standard action to use the aid another action. This represents an extra pair of eyes observing the enemy, giving orders to the crew, or simply helpful advice. The helping character makes a sailing check as well. If the result is 10 or higher, the pilot gains a +2 bonus on her sailing check. Only one character can use the aid another action to help a pilot on a single sailing check.
Controlling a Ship Outside of Combat: Since piloting a ship outside of combat is easily accomplished by taking 10 on the skill check, sailing checks are not normally needed. Almost every character can do it with relative ease; the DCs are given only to adjudicate special situations that may come up in your game.
Controlling a Ship without the Proper Skill: If a pilot lacks the proper skill to control a ship, the pilot can always make a Wisdom ability check instead of the appropriate sailing check. A pilot can even take 10 (when outside of combat) or gain the benefits of the aid another action when using Wisdom instead of the ship’s normal sailing skill.

Control Devices
Every vehicle has a control device for steering. A control device is typically an object with object immunities and resistances and with its own statistics. The following are some of the typical control devices for ships, plus their usual Armor Class, hit points, and hardness.
When a control device gains the broken condition, all sailing checks take a –10 penalty. When a control device is destroyed, a ship cannot be piloted until the control device is repaired.

Control Device AC Hit Points Hardness
Oars* 12 10 per oar 5
Steering wheel 10 25 5
Tiller 10 25 5
Magically treated** ×2 ×2
  • Oars gain the broken condition if at least half the oars on a ship are destroyed.
    • More information on magically treated control devices can be found in Ship Improvements.

Propulsion and Sailing Skills
Every vehicle has a means of propulsion. Boats and ships are propelled by currents, muscle, wind, or all three forces. The method of propulsion typically affects the speed and maneuverability of a ship, but more importantly, determines the required skill needed to control the ship. Controlling a ship takes common sense, awareness, intuition, and often some amount of skill in the ship’s means of propulsion. In the case of wind or current propulsion, it is about using the current and tools like sails, oars, or a rudder to move the ship. In the case of muscle propulsion, it is about guiding creatures to move the ship. The following are the general methods of ship propulsion, along with the skills typically needed to pilot ships propelled by the specified means.
Current: All boats and ships can use water currents for propulsion, but ships that only rely on currents for propulsion are somewhat limited. These vehicles can only move in the direction and at the speed of a current unless they also employ some other means of propulsion or manipulation, and thus often have an additional form of propulsion, such as muscle in the case of a rowboat, or wind in the case of a sailing ship. A current-propelled ship requires a Profession (sailor) check for the sailing check.
A current-propelled ship’s maximum speed depends on the speed of the current (often as high as 120 feet). The acceleration of a current-propelled ship is 30 feet.
Muscle: Muscle-propelled ships use oars and rowers to push the ship forward. Sailing skills for muscle-propelled ships tend to be Diplomacy, Intimidate, or Handle Animal, depending on the intelligence and attitude of the creatures supplying the muscle for the propulsion.
For intelligent creatures, use Diplomacy if the creatures providing the propulsion have an attitude of indifferent, friendly, or helpful. If the creatures providing the propulsion are friendly or helpful, Diplomacy sailing checks are made with a +5 bonus. An average crew is considered indifferent, though a particularly loyal crew might be considered friendly. Intimidate is used for intelligent creatures with an attitude of unfriendly or hostile, such as captive rowers on a slave galley. Handle Animal is used if the creatures providing the propulsion are not intelligent.
The maximum speed and acceleration of a muscle-propelled ship depends on the number of creatures providing the propulsion, but most muscle-propelled ship have a maximum speed of 30 feet and an acceleration of 30 feet. Larger muscle-propelled ships with many rowers have a maximum speed of 60 feet and an acceleration of 30 feet.
Oars: All muscle-propelled ships require the use of oars. Oars have their own statistics.
Wind: Wind-propelled ships use sails to harness the power of the wind for propulsion. A wind-propelled ship requires a Profession (sailor) check for the sailing check. Small wind-propelled ships can move at a maximum speed of 30 feet. Larger ships that are also muscle-propelled often have a maximum speed of 60 feet when using only wind propulsion. Large ships with multiple masts and many sails can have maximum speeds of up to 90 feet. The acceleration of a wind-propelled ship is 30 feet.
All wind-propelled ships can move twice their normal maximum speed when moving in the direction of the wind. A ship using wind propulsion cannot move in the opposite direction from the wind.
Sails and Rigging: All wind-propelled ships require the use of sails and rigging. To move at full speed, a ship requires 10 5-foot squares of sails per mast per square of the ship. For example, a 3-square ship with three masts requires 90 squares of sails. Sails have their own statistics.
Mixed Means of Propulsion: Some ships use multiple forms of propulsion. Multiple methods of propulsion add f lexibility and can work in concert to create faster movement. If a ship has two means of propulsion, such as wind and muscle, it generally adds its two maximum speeds together to determine its maximum speed. Acceleration remains the same. Nothing is added for a third form of propulsion, except for the f lexibility of having a back-up form of propulsion. A ship with multiple methods of propulsion often requires a large crew to get it going and keep it moving.

Evasion and Pursuit
On the wide, open sea, one ship can spot another from miles away, making it virtually impossible to surprise another ship. If both ships want to engage in combat, the ships close with one another and begin ship-to-ship combat normally. If one ship wants to avoid combat, however, a chase ensues. At the GM’s discretion, a faster ship can always catch a slower ship, but even slow ships can take advantage of favorable winds, currents, or coastal terrain to make good their escape.
When two ships first encounter one another, the pilots of the two ships must make three opposed sailing checks. Whichever pilot wins at least two out of three of the opposed checks is victorious. If the pursuing ship wins, it catches up to the f leeing ship and ship-to-ship combat begins. If the f leeing ship wins, it escapes. If the result is a tie, the pilots should begin a new series of three opposed checks.
Such chases can take days, as one ship struggles to outmaneuver the other. At the GM’s discretion, roll 1d4 to determine the number of days a chase lasts.
Withdrawing: Once in ship-to-ship combat, a ship can withdraw from combat by simply moving off the edge of the battle mat, ending ship-to-ship combat immediately.
At the GM’s discretion, the ship has either escaped completely, or the two ships can go back to the evasion and pursuit rules above

Ship-to-Ship Combat

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