Naval Combat

Whether sailing to war or hunting notorious pirates, ships make deadly weapons and dramatic battlefields. This section provides guidance on using ships in combat.  

Ships and Initiative

A ship rolls initiative using its Dexterity, and it uses its crew's quality score as a modifier to that roll.   On a ship's turn, the captain decides which of the ship's actions to use. In the even that the captain is unable to communicate with his crew, such as being overboard, stuck in a zone of silence, or dead, the first mate decides. If the first mate is incapacitated, it moves on to whichever member of the ship's crew is considered the most senior, which is usually the bosun.   Optionally, everyone on board a ship shares initiative with the ship.  

Ships and Movement

Unlike creatures and land vehicles, sailing ships are unable to start and stop on a whim. If a ship doesn't take the Move action on its turn, it moves half its sails' speed directly forward.   A ship may have multiple move speeds, it decides which method it uses when it takes the Move action. A ship can't use the same move speed more than once each turn. For example, if a ship has enough crew to have 3 actions per turn, as well as a move speed from its sails and a move speed from its oars, it can spend one of its actions to take the Move action using its sails, moving up to the sails' move speed. It can then spend another Move action using its oars, moving up to the oars' move speed. It then can't take the Move action again and do something else with its remaining action.   A ship with sails is heavily influenced by the wind. A ship's sails have 4 movement speeds: its default speed, its speed with the wind (i.e it is facing the same direction the wind is blowing), its against the wind(facing directly opposite the wind), and its speed near-against the wind (i.e facing 5 feet away from directly opposite the wind. For example if the wind is blowing north, then the ship is near-against the wind if it is facing south-east or south-west). A sail's speed against the wind is always 0.  

Special Officer Actions

During combat, officers aboard the ship have access to special actions they can do on their turn.

Captain and First Mate

Take Aim

As an action, the captain or first mate directs the crew's firing, aiding in aiming one of the ship's weapons. Select one of the ship's weapons that is within 10 feet of the officer. It gains advantage on the next attack roll it makes before the end of the ship's next turn.

Full Speed Ahead

As an action while on deck, the captain or first mate can exhort the crew to work harder and drive the ship forward faster. Roll a d6 and multiply the result by 5. Apply the total as a bonus to the ship's speed until the end of the ship's next turn. If the ship is already benefiting from this action's bonus, don't add the bonuses together; the higher bonus applies.

Attack!

As an action, the caption or quartermaster can command any number of the crew to cease helping with the ship and instead act as individual combatants. Subtract the number of crew commanded to attack from the effective crew of the ship and place them somewhere aboard the ship. In combat, they act on the ship's turn and attempt to follow the last order given. The captain or quartermaster can command any number of crew to return to their ship posts by taking this action again. Crew cannot return to their posts if they can't hear the officer or if a hostile creature is within 5 feet. Most crew have the bandit stat block.

Double Time(captain only)

Provided your crew can hear you, you shout out inspiration or threats at your crew to work double time. If you succeed on a Charisma (Persuasion or Intimidation) check of 15 (20 if the Ship’s total hit points are halved), the Ship gains an additional action this round. You add or subtract half of the crew's Morale Bonus (rounded down) to this check. This does not stack with the musician's Musical Coordination action. This additional action can be to have the ship move a second time.  

Bosun

Slapdash Repair

As an action, the bosun can attempt to quickly patch holes and repair serious damage, to help keep the ship afloat. Whilst within 5 feet of a component that doesn't have all its hit points, the bosun can repair it, granting that component a number of temporary hit points equal to 2d8 + the bosun's carpenter's tools bonus. These temporary hit points last for 10 minutes. If the component was at 0 hit points, it becomes operational whilst it has these temporary hit points.  

Helmsman

Emergency Turn

As a reaction when their ship would be raked (see further in this article), the helmsman can attempt to abruptly turn the ship to minimise the damage. When within 5 feet of the helm and the ship is hit with an attack that would rake it, the helmsman can make a DC15 strength-based water vehicles check. On a success, the helmsman can rotate the ship 45 degrees in a direction of their choice, turning the raking hit into a normal one.

Brace for Impact

As an action whilst within 5 feet of the helm, the helmsman can help brace the ship for collision with a large object. Until the start of the helmsman's next turn, the ship has resistance to all damage received from crashing into something. Additionally, crashing into a creature or object deals additional damage equal to the helmsman's water vehicles bonus.

Shield the Crew

A skilled helmsman is adept at quickly manoeuvring or turning the ship's deck so that it takes the brunt of a widespread attack rather than the crew. When the top deck of the ship is subjected to an area of effect and the ship itself succeeds on the saving throw, the helmsman can use their reaction to tilt the deck of the ship away from the effect, giving the crew advantage on their own saves to avoid the effect, but with the downside turning the ship's own success into a failed saving throw.  

Master Gunner

Man the Gun

As an action, the master gunner can take charge in aiming one of the ship's weapons. Select one weapon within 5 feet of the master gunner. The gunner can use their strength and proficiency bonus for the to hit roll of the weapon instead of the weapon's normal to hit bonus for the weapon's next attack roll. In addition, they may add their proficiency bonus to the damage roll of the weapon's next attack. The gunner can also apply any features that they can normally apply to ranged attacks, such as battlemaster manoeuvres or the hail of thorns spell, spending the necessary resources and actions as usual.   After taking this action, the Master Gunner cannot move away from the weapon until the end of the ship's next turn.

Coordinate Fire

Master gunners are experts at paying attention to the listing and tilting of a ship's deck to time the firing of cannons such that they can target precise parts of an enemy ship. As an action, the master gunner selects a cannon or multiple cannons of the same type on the same deck that they are on (for example, the gunner can select all 8-pound cannons aboard the ship). Each of those weapons no longer has disadvantage to attack components that aren't the hull, and can target those components in their second range increment (albeit at disadvantage, following normal ranged weapon attack rules).   If the master gunner is not on the same deck as the selected weapons on the ship's next turn, the benefits of this action are lost.  

Surgeon

Patch up

With access to the quick and dirty techniques and tools of a ship's doctor, you are able to quickly patch together wounds to get your crew up and running. It'll probably be fine. As an action whilst carrying a healer's kit aboard your ship, you can heal an injured crewmate's wounds. That crewmate gains a number of temporary hit points equal to 1d6+your intelligence/wisdom modifier (your choice), plus a number of thp equal to the target's maximum number of hit dice. If you grant these temporary hit points to a creature at 0hp, that creature comes to consciousness. These temporary hit points disappear after 1 minute. If a creature still has 0hp at the end of that minute, they fall unconscious again and resume death-saving throws if they were dying before being patched up.   A creature can only benefit from being patched up once per long rest.

Anatomical Knowhow

When fighting a large or larger creature, you can attempt to recall knowledge on the creature and give pertinent advice on where to shoot. Make a DC16 Intelligence (Nature, Religion, or Arcana, depending on the creature) check. You add or subtract half of the crew's Morale Bonus (rounded down) to this check. On a success, one ship weapon of your choice has advantage on its next attack roll made against a large or larger creature you can see. The DC for this check can be lower or higher as the DM sees fit depending on the rarity or familiarity of the creature.  

Cook

Gastronomical Knowhow

When fighting a large or larger creature, you can use your vast experience of preparing various strange beasts for meals to make educated guesses about their anatomy, providing useful advice about where to shoot. Make a DC16 Wisdom (chef's utensils) check. You add or subtract half of the crew's Morale Bonus (rounded down) to this check. On a success, one ship weapon of your choice has advantage on its next attack roll made against a large or larger creature you can see. The DC for this check can be lower or higher as the DM sees fit depending on the rarity or familiarity of the creature.  

Provide Refreshments

As an action whilst aboard your ship, you can hand out refreshments to keep the crew in good shape and well hydrated during the intense labour of a ship battle. The ship gains a refreshment die, which is a d4. When the ship fails a d20 roll, it may roll its refreshment die and add it to the total, potentially turning a failure into a success. The die is then expended. A vehicle may only have 1 refreshment die at a time, and it is lost after 10 minutes. This action expends all your movement as you race up and down the deck to hand out your supplies.   The die increases to a d6 at level 5, a d8 at level 9, a d10 at level 13, and finally a d12 at level 17.  

Musician

Musical Coordination

Provided your crew can hear you, you lead a shanty or play a drum beat or tune to coordinate the crew's actions, giving them the working power of a much larger crew. If you succeed on a Charisma (Performance) check of 15 (20 if the Ship’s total hit points are halved), the Ship gains an additional action this round. You add or subtract half of the crew's Morale Bonus (rounded down) to this check. This does not stack with the Captain's Double Time action. This additional action can be to have the ship move a second time.    

Navigator

Angle Trajectory

By factoring minor changes in the wind and quickly calculating distance and speed, you can attempt to further optimize the aim of a ranged ship weapon. Make a DC15 Intelligence (Navigator's Tools) check. You add or subtract half of the crew's quality score (rounded down) to this check. On a success, one ranged ship weapon of your choice instead only suffers a -2 penalty to attacking in its long range as opposed to rolling with disadvantage.  

Predict Wind Change

Through quick and careful analysis of the wind and its current patterns, you can potentially reduce the effects of sailing with headwind! Make a DC20 Intelligence (Navigator's Tools) check. You add or subtract half of the crew's quality score (rounded down) to this check. On a success, if the speed of the ship is reduced by a factor of wind, the ship ignores this for its next turn.  

Crew in Combat

Managing a ship's entire crew in combat can prove cumbersome, especially as larger ships often host dozens of sailors. Typically the crew is too busy managing the ship to do anything else during combat. Don't worry about tracking their specific positions unless you want to add that complexity. You can assume that the crew is evenly divided among the upper two decks of a ship.  

Crew Casualties

Slaying a ship's crew reduces the number of actions most ships can take, making the crew a tempting target in combat. Resolve individual attacks as normal, using the guidelines for resolving many, identical attacks at once from the Dungeon Master's Guide as needed.   In the case of effects that target an area, you can decide how many crew are in the area of the effect using the following table (rounding up). If an area of effect is longer than the length of the ship in question, then use the ship's length instead. For example, if an 80-foot-long ship is hit with a 50ft. radius (100ft. diameter) sphere effect, use the entry for a 40ft. radius (80ft. diameter sphere).  

Cone	Cube/Square	Cylinder radius	Line	Sphere/Circle Radius	No. of Crew targeted
10ft.	5ft.	5ft.	30ft.	5ft.	1d4
20ft.	10ft.	10ft.	60ft	10ft.	2d4
30ft.	15ft.	15ft.	90ft.	15ft.	3d4
40ft.	20ft.	20ft.	120ft.	20ft.	4d4
50ft.	25ft.	25ft.	150ft.	25ft.	5d4
60ft.	30ft.	30ft.	180ft.	30ft.	6d4
70ft.	35ft.	35ft.	210ft.	35ft.	7d4
80ft.	40ft.	40ft.	250ft.	40ft.	8d4
90ft.	45ft.	45ft.	280ft.	45ft.	9d4
100ft.	50ft.	50ft.	310ft.	50ft.	10d4

Crashing a Ship

If a ship moves into the space occupied by a creature or an object, the ship might crash. A ship avoids crashing if the creature or object is at least two sizes smaller than it.   When a ship crashes, it must immediately make a DC 12 Constitution saving throw. On a failed save, it takes damage to its hull based on the size of the creature or object it crashed into, as shown on the Crash Damage table. It also stops moving if the object or creature is one size smaller than it or larger. Otherwise the ship continues moving and the creature or object collided with moves to the nearest unoccupied space that isn't in the ship's path. At the DM's discretion, an object that is forced to move but is fixed in place is instead destroyed.   A creature or object struck by a ship must make a Dexterity saving throw with a DC equal to 10 + the ship's Strength modifier, taking damage based on the ship's size (as shown on the Crash Damage table) on a failed save, or half as much damage on a successful one.

Crash Damage

                                                           

Size	Bludgeoning Damage
Small	1d6
Medium	1d10
Large	4d10
Huge	8d10
Gargantuan	16d10

Ship Weapons

Ships use seige weapons as described in the dmg. They are fired using one the ship's actions. When a ship uses its action to fire a weapon, it fires all weapons of that same type. The number of actions a ship can perform is based on the amount of crew it carries(detailed in its statblock). Ship weapons are immune to poison and psychic damage.  

Traditional Seige Weapons

Different ships have a variety of weapons that they can deploy to blast their enemies out of the water. Whilst many ships rely on cannons, some pirates prefer an old fashioned method, employing traditional seige weapons. These weapons have an advantage in that they can be mounted on rotatable platforms, granting them the ability to easily target any part of an enemy ship. Such weapons must be mounted the top deck of a ship, which typically only has room for 4 large weapons, for 2 huge ones. Traditional seige weapons have disadvantage to hit targets of their size or smaller.                                          

Weapon	Damage	Cost
Ballista	3d10 piercing	400gp
Mangonel	5d10 bludgeoning	1,000gp
Trebuchet	8d10 bludgeoning	2,000gp

Ballista

Large object
AC: 15
HP: 50
A ballista is a massive crossbow that fires heavy bolts, or harpoons for latching onto and reeling in enemy ships or large creatures.
Bolt: +6 to hit, range 120/480ft., Hit: 3d10 piercing damage.
Harpoon: +6 to hit, range 100/400ft., Hit: 1d10 piercing damage, and the target is grappled by the ship, and the ballista can't fire at another target. As one of its actions on subsequent turns instead of firing the ballista, the ballista can instead attempt to pull the grappled target closer. The target makes an athletics check contested by the ship's strength. If the ship succeeds, the target is pulled 30 feet closer if it is the same size as the ship, 40 feet if it is one size smaller, 50 feet if two or more sizes smaller, or 10 feet if it is one size larger than the ship. If it is two or more sizes larger than the ship, the ship instead is pulled 10 feet closer to the target. The rope attached to the harpoon has an AC of 15 and 10 hit points, and is immune to psychic and poison damage. A creature grappled by the ship has disadvantage on attack rolls to hit the rope. Multiple harpoons can be embedded in a creature or object.  

Mangonel

Huge object
AC: 15
HP: 100
A mangonel is a type of catapult that hurls heavy projectiles in a high arc. This payload can hit targets behind cover.
Mangonel Stone: +5 to hit, range 200/800 ft. (can't hit targets within 60 feet of it). Hit: 5d10 bludgeoning damage.
Burning Tar Stone: +5 to hit, range 200/800ft. (can't hit targets within 60 feet of it). Hit: 3d10 fire damage, and a 10 foot radius circle is set alight. Creatures inside the circle and the ship take 2d10 fire damage at the start of their turns. A ship set ablaze can use one of its actions to have the crew put the fire out. The crew rolls a D20 and adds their crew quality score. On an 11 or higher, the fire is put out. Risk: Using fire aboard a ship is a risky business. On a natural 1, a mishap occurs, and the Burning Tar Stone instead hits the ship's hull or a component on the top deck at random.    

Trebuchet

Huge object
AC: 15
HP: 150
A mangonel is a powerful catapult that hurls its payload in a high arc. This payload can hit targets behind cover.
Trebuchet Stone: +5 to hit, range 300/1,200 ft. (can't hit targets within 60 feet of it). Hit: 8d10 bludgeoning damage.
Burning Tar Stone: +5 to hit, range 300/1,200ft. (can't hit targets within 60 feet of it). Hit: 6d10 fire damage, and a 10 foot radius circle is set alight. Creatures inside the circle and the ship take 2d10 fire damage at the start of their turns. A ship set ablaze can use one of its actions to have the crew put the fire out. The crew rolls a D20 and adds their crew quality score. On an 11 or higher, the fire is put out.[be] Risk: Using fire aboard a ship is a risky business. On a natural 1, a mishap occurs, and the Burning Tar Stone instead hits the ship's hull or a component on the top deck at random.  

Ammunition

                                                                         

Name	Cost	Damage	Weight
Ballista Bolt	1gp	3d10 piercing	10lbs
Harpoon	1gp	1d10 piercing	6lbs
Mangonel Stone	2gp	5d10 bludgeoning	45lbs
Burning Tar Stone (Mangonel)	3gp	3d10 fire	45lbs
Trebuchet Stone	4gp	8d10 bludgeoning	100lbs
Burning Tar Stone (Trebuchet)	5gp	6d10 fire	100lbs

Cannons

Most ships in the current era deal damage using cannons. Cannons are available in a variety of sizes, from the small maneuverable guns found on the top deck to the heavy guns found on gun decks. Most cannons are made of cast iron, but older cannons are made from cast bronze. Cannons are described by the size of the cannonball they fire, ranging from the small 1-pounder swivel guns to the heavy 32-pounder guns found on the battlements of coastal fortresses. The larger the ship, the greater the quantity and size of its cannons. With the exception of swivel guns, cannons are far less manoeuvrable than traditional siege weapons and are difficult to be aimed up or down without the aid of a master gunner. As such, a cannon on a gun deck has disadvantage on attack rolls against anything on a ship's top deck, and a cannon on a ship's top deck has disadvantage on attack rolls against a ship's sails. A cannon that has disadvantage in this way cannot target a component outside of its first range increment. Cannons can also only fire in a straight line out from their position on the ship - being the port side(left) or starboard side(right). As such, a ship can typically only fire half its cannons at a target unless it has adversaries on both sides of it. Attacks made with an 8-pound or heavier cannon have disadvantage against Large or smaller targets, and attacks made with 24-pound or heavier cannons have disadvantage against Huge or smaller targets.  

Raking

Cannonballs are heavy, dense balls of iron that rip through ships at immense speeds. Many ships aim to hit a ship from the front or behind so that the cannonball travels through as much of the ship as possible, dealing huge damage. This is known as raking. When an attack from a cannon that deals bludgeoning damage hits a ship on its bow(front) or stern(rear), that shot deals an additional 1d10 bludgeoning damage. Swivel guns cannot be used to rake.  

Broadside

Ships in the current age tend to have a great many cannons. The largest battleships can have as many as 30 guns across their gundecks. Rather than resolve 15 attacks every turn, a ship can instead choose to broadside, resolving all cannon shots at once. Broadsiding replaces a ship's normal Fire Cannons action.   First, determine how many cannons can hit your target. Then treat the cannon fire as a line effect with a width equal to the distance between the furthest apart cannons you are firing and a length equal to the cannon's maximum range. The target then makes a dex or constitution saving throw against a DC equal to 8 + the to-hit bonus of the ship's cannons. On a failure, the target takes damage as if all the cannons had hit it. On a success, the target takes half as much damage. Be sure to separate each cannon's individual damage, as some shot's damage might be below the target's damage threshold.   If the cannons would have disadvantage to hit a target, that target has advantage on its saving throw. Likewise, if the cannons would have advantage to hit a target, that target has disadvantage on its saving throw. If the target rolls a natural 20, it takes no damage. On a 1, it takes an additional 1d10 damage per cannon that hit it.   If the target is outside the cannons' first range increment, the target instead takes half damage on a failed save and no damage on a successful one.   If a cannon has different properties from the rest of the other cannons of its type on board, such as using different ammunition (i.e one is using grapeshot whilst the rest uses normal ammunition), an officer has taken the Take Aim or Man the Gun action on it or one of them has disadvantage/advantage on attack rolls, resolve that specific cannon's attack separate from the broadside.  

Types of Cannon

                                                                       

Weapon	Damage	Cost
Swivel Gun	2d6 bludgeoning	250gp
8-pound Cannon	3d10 bludgeoning	750gp
12-pound Cannon	4d10 bludgeoning	1,000gp
16-pound Cannon	5d10 bludgeoning	1,500gp
24-pound Cannon	6d10 bludgeoning	2,000gp
32-pound Cannon	7d10 bludgeoning	3,000gp

Swivel Gun

AC:17
HP:15
A swivel gun (or patarero) is breech loaded with 1-pound balls of cast iron, or a canvas bag full of musket balls called a grapeshot. It can be turned to attack nearly any target, but it is not recommended to fire across your own deck. An attack fired across your own deck that misses by 5 or more hits a target on your own deck. Swivel guns are positioned on the top deck of a ship and can be moved around the deck with minimal effort. They can also be added to a longship’s bow. ¼ pound of gunpowder is required to fire this weapon.
1-pound Shot: +6 to hit, range: 150/300ft., Hit: 2d6 bludgeoning damage.
Grapeshot: 30 foot cone. Creatures and objects in the area make a DC12 Dex save or take 2d6 bludgeoning damage, or half as much on a success.  

8-pound Cannon

AC:17
HP:40
This weapon uses gunpowder to fire 8-pound balls of cast iron. Two pounds of gunpowder are required to fire this weapon.
8-pound Shot: +6 to hit, range: 400/1,600ft., Hit: 3d10 bludgeoning damage.    

12-pound Cannon

AC:17
HP:50
This weapon uses gunpowder to fire 12-pound balls of cast iron. It can also be used to fire a chain and bar shot, two balls connected by a chain used for destroying masts, an explosive shot, or a grapeshot. Three pounds of gunpowder are required to fire this weapon.
12-pound Shot: +6 to hit, range: 500/2,000ft., Hit: 4d10 bludgeoning damage.
Chain and Bar Shot: +6 to hit, range: 250/1,000ft., Hit: 4d8 slashing damage. If the attack target's a ship's sails, it has advantage and deals an additional 4d8 slashing damage.
Explosive Shot: +6 to hit, range: 400/1,600ft., Hit: 4d10 fire damage. A flammable object ignites if it isn't being worn or carried. Any creature within 5 feet of the target must make a DC12 dex save or take 1d10 fire damage.
Grapeshot: 90 foot cone. Creatures and objects in the area make a DC12 Dex save or take 3d8 bludgeoning damage, or half as much on a success.  

16-pound Cannon

AC:17
HP:60
This weapon uses gunpowder to fire 16-pound balls of cast iron. Four pounds of gunpowder are required to fire this weapon.
16-pound Shot: +6 to hit, range: 550/2,200ft., Hit: 5d10 bludgeoning damage  

24-pound Cannon

AC:17
HP:75
This large cannon is called a ship wrecker, and is found only on the largest ships or the battlements of coastal fortresses. This weapon uses gunpowder to fire 24-pound balls of cast iron. Six pounds of gunpowder are required to fire this weapon.
24-pound Shot: +6 to hit, range: 600/2,400ft., Hit: 7d10 bludgeoning damage    

32-pound Cannon

AC:17
HP:100
This massive cannon is found only on the battlements of coastal fortresses and are too large to fit on even galleons. This weapon uses gunpowder to fire 32-pound balls of cast iron. Eight pounds of gunpowder are required to fire this weapon.
32-pound Shot: +6 to hit, range: 700/2,800ft., Hit: 9d10 bludgeoning damage  

Mortar

AC: 17
HP: 80
A mortar is a cannon that fires its payload in a tall arc and is typically used to attack land fortifications from the sea, able to fire clean over fortress walls. Ships that employ mortars are called bomb sketches. Unlike cannonades, mortars are typically mounted to fire from the bow or stern of a ship. Mortars ignore cover.
16lb shot: +5 to hit, range 600/2,400 ft. (can't hit targets within 100 feet of it). Hit: 5d10 bludgeoning damage. [be] Explosive Shell: +5 to hit, range 600/2,400ft. (can't hit targets within 100 feet). Hit: 4d10 fire damage. Any creature within 5ft (1d6 crew) must make a DC12 dex save or take 2d10 fire damage, 1/2 on a success.  

Ammunition

                                                                                                                                     

Name	Cost	Damage	Weight
Cannonball(1lb)	5sp	2d6 bludgeoning	1lb
Cannonball(8lb)	2gp	3d10 bludgeoning	8lb
Cannonball(12lb)	3gp	4d10 bludgeoning	12lb
Cannonball(16lb)	5gp	5d10 bludgeoning	16lb
Cannonball(24lb)	6gp	7d10 bludgeoning	24lb
Cannonball(32lb)	8gp	9d10 bludgeoning	32lb
Chain and Bar Shot	10gp	4d8 slashing	24lb
Explosive Shot	25gp	4d10 fire	24lb
Grapeshot(1lb)	2gp	-	1lb
Grapeshot(12lb)	12gp	-	24lb
Gunpowder Keg	55gp	-	50lb
Gunpowder Barrel	100gp	-	100lb