D&D 5E Ship to Ship Crew Combat Options

[DM_Jeff]

Just asking for general inquiry, what DM's prefer regarding running combats between ship crews (not PC's) during play.

* Ghosts of Saltmarsh offered "Typically the crew is too busy managing the ship to do anything else during combat." Yeah.

* I used to describe it in the background, changing the flavor depending on which side was winning, the "PC's vs Villains or Monsters" bit. Worked OK, but not too satisfying.

* Use some kind of quick and dirty mass combat system, nice and small, to derive the outcome (never found one that wasn't too much trouble).

* My latest experiment with this? Stat up ship crews as swarms. Yes, I'm serious. Then they can duke it out and you get some satisfaction.

Anyway I know in the end the answer is "whatever you prefer", but I was just curious what others use as options for their game?

 

[Mort]

* I used to describe it in the background, changing the flavor depending on which side was winning, the "PC's vs Villains or Monsters" bit. Worked OK, but not too satisfying.

This is what I did last session, worked well enough for the session.

* My latest experiment with this? Stat up ship crews as swarms. Yes, I'm serious. Then they can duke it out and you get some satisfaction.

That's actually not bad, though I think the numbers are a bit high.

My thought, if ship combat becomes more of a thing, was to treat the crew as a hazard, difficult terrain, some damage etc. Haven't worked out the details yet.

 

[iserith]

In a recent Eberron game wherein the PCs were fighting boarders on an airship, the situation was that the crew were trying to get passengers to safety as the ship was crashing. So I set it up where I put crew member tokens on the board and that space plus 5 feet around them was difficult terrain, half cover, and you could go into the space to take the Hide action. They would be removed from the map if they were hit with an AOE that did 10 or more damage.

The idea was that they were not fighting and were sometimes helpful terrain and sometimes not, depending on the situation. The PCs did the heavy-lifting in the actual combat.

 

[Lanefan]

To clarify - are you asking about situations where two or more ships have got close enough for the crew to potentially interact in melee (e.g. the ships have collided, or one has sent boarders over to the other)? Or are you referring to situations where the ships are still apart and combat is mostly by missile fire e.g. bow, cannon, musket, etc.?

 

[Bacon Bits]

Last time I did a ship-heavy campaign, I assumed that any ship intending to attack another (so pirate, privateer, or warship) would have a moderate contingent of marine soldiers. Other ships would have a small contingent. The standard method of attacking that everyone would expect would be grappling, where the attacking ship would maneuver to get close enough to throw lines with grappling hooks on them to pull the ships along side each other, at which point the attackers would invade and try to kill everyone on board. Really dedicated attack ships might employ ogres with grappling chains. The primary defense, then, is speed. You can't attack what you can't catch.

Once two ships are grappled, there's a lot of danger. Anyone falling between the two ships is liable to get crushed. The ships themselves might rip each other apart if the seas are rough enough. There's essentially no control at all, too, as the sails become tangled and neither rudder is going to be strong enough to control both ships. Because of that, once grappling has begun and the crew has failed to cut the lines, basically everyone stops sailing and starts fighting.

Other methods of attack would be fire arrows (for the sails), magic if a spellcaster were on board, and the odd catapult (loaded with solid shot or chain to rip up the rigging or alchemists fire) or a ballista (to pierce the hull) on dedicated warships. Warships designed for ramming would also exist, powered by galley slaves and equipped with large rams intended to break apart other ships.

I ran a combat of five small, fast attacking pirate ships against two "lightly" defended large merchant vessels (I say "lightly" because the PCs were the defenses of one ship). I had two ships attack each merchant, with the last ship taking damage from the PCs before it could engage. The second ship had no PCs on it, so all I did was decide how many of each type of sailor there were (something like 18 marines vs 4 mercs and 25 odd crew) and rolled one attack for each each round spread out as evenly as possible (3 attacks against the mercs, the rest against the crew). Each "hit" took off one hit die, so if the marines were in breastplate with 3 HD then 3 hits would kill a marine. The mercs were 5 HD in chain mail, and the crew were 1 HD with no armor. (Yes, the marines were intended to win on the second ship.) It was close enough to real combat even if we skipped the benefits of higher ability scores.

On board the PC's ship, I ran combat standard if any of the PCs were involved, but I used the accelerated combat with the 1 HD crew and just took 1/3 hp when the marines were hit by the crew. It went fast enough for me, but I have a lot of d20s.

 

[DM_Jeff]

To clarify - are you asking about situations where two or more ships have got close enough for the crew to potentially interact in melee (e.g. the ships have collided, or one has sent boarders over to the other)? Or are you referring to situations where the ships are still apart and combat is mostly by missile fire e.g. bow, cannon, musket, etc.?

The former, where the ships have connected and boarding actions are underway.

 

[77IM]

I like your reasoning, but I think you should scale the HP and damage by the number of crew members. 10-40 is just too big of a spread. Swarms typically do half damage when they are at half hit points, although I think a better idea is to give them multiple attacks.

So you could do something like: The swarm has X hit points per 10 crew members, and 1 attack per 10 crew members. This lets you very easily represent crews of different sizes. E.g. if the PCs have 24 crew members, they get 2X hit points and can make 2 attacks; if you're repelling a longboat with 80 vikings, the enemy crew has 8X hit points and can make a whopping 8 attacks. (I think that 8 attacks is not too many, but YMMV.)

I feel icky about the resistance/vulnerability based on effect area. I'd just say "resistant to single-target attacks; vulnerable to area effects" and leave it at that. Things that are neither attacks nor area effects deal normal damage (e.g. magic missile, ending your turn next to a flaming sphere, etc.).

I also don't like the area-effect archery volley. If you go the route of multiple attacks, then a large swarm can just target multiple people.

You could actually make this a restriction on the multiattack: "The swarm makes 1 attack per 10 crew members, but can't attack the same target twice." This lets your 24-person crew live a little longer against the 80-person longboat, while making the enemy crew into more of a hazard for the players. A slightly softer restriction would allow them to attack the same target twice, but not 3 times, or maybe each attack against the same target after the first is at disadvantage (because it's hard for all the attackers to reach the target).

 

[DM_Jeff]

All good things to think about - lots of good advice going forward, thanks!

 

[robus]

A poster[1] presented this as a way to handle a large battle that while featuring the PCs let them get into the action and provide aid as needed. I've used it a couple of times and it's worked out well without turning into a lot of DM dice play:

Mass Combat

Divide the Battlefield into Zones
There can be a handful or many depending on the size of the conflict. Only use as many as you think that you will need. The PCs will begin in one of these zones along with enemy forces that oppose them. This may be a random placement or against specific enemies depending on the setup and intelligence available to both forces.

Place allies and other enemy forces in the remaining zones. Again base these starting forces according to the information available to them. At this point all forces should be deployed in zones. Draw a rough sketch map of the zones and note which forces are in each one.

Determine Match-up in each Zone

Except the one the PCs are in!

This is a rough level compatibility test. Look at factors such as numbers/ratio, individual prowess of combatants, special abilities, etc. This is where we determine if there is enough of a mismatch to apply modifiers to the conflict. A positive modifier means an edge for the PCs allies. A negative modifier means an edge for the PCs enemies. For each zone determine the match-up modifier in a range of 0 to +/- 4.

This is where being familiar with the participants stats is important. Only a severe advantage should get a +/- 4 modifier such as being outnumbered 3 or 4 to 1, or a force of regular men fighting half or more of their number of ogres. Remember special abilities. If the entire enemy force is resistant or largely immune to the other side's attacks (soldiers vs wererats) that would count as a huge advantage.

This is also a good time to assign modifiers for information the players may have that is shared with allies or for good tactical deployment depending on the setup and how much time there is to prepare.

Fight!

Each round determine the status of the battle happening in each zone the PCs are NOT in. Roll 3d6 for each zone of battle applying the modifier for that zone. Use this table to apply the outcome of a round:

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<= 4: Allies in severe trouble- enemy gains 3 points​

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5-8: Allies in trouble-enemy gains 2 points​

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9-10: Struggle locked but stable- enemy gains 1 point​

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11-12: Struggle locked but stable- allies gain 1 point​

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13-16: Enemies in trouble- allies gain 2 points​

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at or above 17: Enemies in severe trouble-allies gain 3 points​

​

The first force in a zone to reach 6 points wins the battle in their zone. Make a note of how the battle in each zone is going. This way you know how the tide is swinging during each round and roughly how long each zone will take to resolve.

Degrees of Victory

Each zone will have a victor. The cost of the victory is determined by the margin ratio:

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6-0: clean sweep, no casualties, enemy largely destroyed​

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6-1: easy victory, 5% casualties, enemy soundly defeated​

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6-2: victory, 10% casualties, enemy defeated​

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6-3: tough victory, 30% casualties, enemy defeated​

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6-4: costly victory, 60% casualties, enemy barely defeated​

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6-5: pyrrhic victory, 80% casualties, victorious unit broken​

​

Movement between Zones

A unit that achieves victory in its zone can then reinforce friendly units in an adjacent zone. It takes 1 round to move to an adjacent zone. A move across 2 zones would require 2 rounds, etc. All units save a broken unit can move to assist allies. The round after joining an allied unit, the reinforcements add a +1 to +5 modifier to their allies in the new zone depending on what shape they were in. A unit moving to assist after a clean sweep victory would add +5 while a unit following a costly victory would add only +1 for example.

All of this can be determined in prep with notes of what is happening in each zone round by round. Now there is a rough outline of how the battle will progress without PC actions. As the players fight their part of the battle and move to help allies in other zones you have a solid idea on what is happening in each place as the PCs get there. The system isn't that difficult to use at the table if you would prefer the flow of battle to be a surprise each round especially if you have players help make the rolls.

[1] I forget who and I think the original post was lost in the big crash a couple of years back - though the search feature of the new forum is super fast! @ExploderWizard was it you perchance?

 

[Inchoroi]

Just asking for general inquiry, what DM's prefer regarding running combats between ship crews (not PC's) during play.

* Ghosts of Saltmarsh offered "Typically the crew is too busy managing the ship to do anything else during combat." Yeah.

* I used to describe it in the background, changing the flavor depending on which side was winning, the "PC's vs Villains or Monsters" bit. Worked OK, but not too satisfying.

* Use some kind of quick and dirty mass combat system, nice and small, to derive the outcome (never found one that wasn't too much trouble).

* My latest experiment with this? Stat up ship crews as swarms. Yes, I'm serious. Then they can duke it out and you get some satisfaction.

Anyway I know in the end the answer is "whatever you prefer", but I was just curious what others use as options for their game?

I haven't actually worked everything out yet, but the plan is to have each PC have a small "mass-combat"-like crew system where they can command them to fight (with rules for PC vs group, etc) or take other "Ship" actions, like raising sail or fighting fires.

Going to use Matt Colville's warfare system as the base for the battle groups, and Colville's system will be used as a base for the actual naval combat.