Age of Sail rules for 5th ed D&D

So after a lot of work and a good bit of reading and stealing ideas from various places, I came up with a set of rules for Age of Sail combat (Ship v Ship, easily used for Ships v. Big Monsters). They're presented here. I finally ran a combat with them last night, my regular game having gotten around to going to sea after 6 levels of dungeonneering on land. I'll post a postmortem for our first playtest of the rules a bit later.

Age of Sail Rules: For 5th ed D&D. These rules should explain how a ship operates in combat against other ships or sea monsters, using a grid map. They’re intended to be used with the stats for ships and artillery in the 5th ed books, as well as the basic combat rules for things like actions, initiative, etc.

1. General
1. Ship Scale Map is 30 ft per square. Placed on the map will be wind speed and direction, and visibility.
2. A ship moves and takes actions on the initiative count of its Captain.
3. Visibility is dependent on weather, clear sky 10 miles away, overcast 5 miles, raining 1 mile and fog 100 to 300 feet.
4. All checks listed herein are base DC 10, subject to situational modifiers.
5. Ships require a minimum number of crew to move and fire guns. For every 30 HPs of damage a ship sustains, one randomly determined crew member will be removed from active duty. The Surgeon can return them to active duty.
6. People on a ship (crew, passengers, etc.) have 1/2 cover from ranged attacks from outside the ship.
2. Ship Actions & Movement
1. All checks to turn, board, accelerate, decelerate, etc. are made by the Captain using his Pilot skill. In the event the Captain takes no piloting actions, a ship moves on its bearing from its last turn at the same speed as last turn.
2. Pilot is both an Dex and a Cha skill. Dex is used if the ship has a crew requirement of 1 like a Keelboat, Cha is used if the ship has a crew requirement greater than 1.
3. All ships have a speed. Sailed ships go double speed with the wind but cannot move directly into the wind. Oarred ships go normal speed all the time.
4. A ship can move on its initiative as per speed, plus take a Dash (double move) or Turn Action (90 degrees max).
5. Ships can Accelerate or Decelerate in increments of 30, or less, per round. E.g. A ship with a max speed of 60 takes 2 turns to go from 0 to max speed or max speed to 0.  
6. A ship without its minimum crew complement, and a captain/helmsman cannot Turn, accelerate or decelerate.
7. A ship performs a Ram by moving at max speed straight into another ship or monster, thereby dealing Ram damage as per ship. A Ram automatically initiates a Board.
8. A ship performs a Board against another ship by ending its move next to that ship and performing a Grapple action. The Boarding Captain’s Pilot check opposed by the Boarded Captain’s pilot check. If attempting to Board an immobilized ship, the check is made with advantage. An immobilized ship cannot break free of a Board.
3. Ship Hit Points and Conditions
1. Ships have hit points and an AC like a creature, they take damage the same way. They typically have a damage threshold as well.
2. A ship automatically fails any dex save (e.g. against a fireball) and is immune to any damage that wouldn’t affect a ship (e.g. poison, psychic).
3. When a ship is between 100% and 50% hit points, it moves and functions as normal.
4. Between 50% and 25% hit points, a ship is immobilized. It can be repaired at sea to 100% HP using magic and/or conventional repairs. A ship regains mobility once repaired above 50% HP.
5. Between 25% and 0% hit points, a ship is immobilized and can be repaired to 50% +1 HP using magic and/or conventional means at sea. It cannot be further repaired unless put in dry dock. A ship regains mobility once repaired above 50% HP.
6. If reduced to 0 HP, a ship begins to sink. It will sink completely in 10 rounds. Damage dealt to a sinking ship speeds sinking by 1 round per 25 damage dealt. It can be repaired only using magical means. If repaired above 0 HP, a ship stops sinking. It can then be repaired as though it was between 25% and 0% HP, explained above.  
4. Cannons - This is specialized artillery. It is not the only type of available artillery.
1. A cannon takes 3 people 25 rounds to load and aim for firing. It cannot be made ready to fire with less than 3 people. See DMG for cannon  stats.
2. A cannon requires 100g worth of blackpowder and a shot worth 30g per firing.
3. Available shot types are: Ball - Deals 8D10 damage to target hit. Chainshot - Deals 10D10, Cannot reduce ship below 50% HP. Scattershot - Deals 8D10 damage, no ship damage but incapacitates one crew per 15 damage dealt.
5. Officers and Actions - To avoid standing around during ship combat, PC’s can take on Officer roles and have something to do.
1. Captain / Helmsman - One person can perform both roles, or two people can do each separately. The ship moves on the Captain’s initiative, and the Captain makes Pilot checks to have the ship Turn, Accelerate, Decelerate, Board, or negotiate other hazards. If two players perform these jobs separately, and both have proficiency in Pilot, they both add their proficiency bonus to the Captain’s Pilot checks.
2. Master of Artillery - One player can be a master of artillery. This player can do the following as an Action on his/her turn:
1. Order Broadside: All ready to fire artillery on a side of the ship (min 2) fire at once. If a target is within close range, make a single attack roll per 2 firing artillery with advantage. For each 2 firing artillery, target takes normal artillery damage on a hit and half artillery damage on a miss.
2. Hustle Crews: Make a DC 10 Cha check to speed up loading time. On a success, -5 rounds until artillery are ready to fire. Only crews that can see and hear the Master of Artillery can receive this benefit.
3. Spot Weakness: Make a DC 10 Wis check to spot a weakness on a target, giving one piece of artillery or attacking character advantage on one attack roll against that target this round. Attacker must be able to see and hear the Officer.
3. Crew Officer - These officers direct the crew sailing the vessel
1. Rally: Make a DC 10 Cha check to grant advantage to the Captain on one Pilot check made this turn. The Captain can only receive this bonus once per turn.
2. Brace for Impact: Order the crew to hunker down for one turn. Until this officer’s next turn, the crew has resistance to all damage other than psychic, and all Pilot checks made by the Captain have disadvantage.
4. Captain’s Officer - These officers assist the Captain.
1. Recon Target: Make a DC 10 Wis check to learn the current HP, flag, remaining crew, or other information about enemy ship. Requires a spyglass.
2. Signal Flag: Communicate a simple message to another ship that can see you using signal flags. DM should decide what can be communicated. E.g. “Follow us.” or “Surrender immediately”.
5. Surgeon - One player with either medicine prof or healing spells can act of ship’s surgeon, getting crew back on their feet during combat.
1. Triage: Make a DC 10 Medicine check or use a spell to return 1 crew member to active duty.

Using postmortems to improve games

Who's had this happen? Everyone comes over, you play, everyone says "Thanks" and then goes home. You pat yourself on the back, and do it again next week. After a while, your game stagnates and dies or your players lose interest and want to play something else, and that's it for the campaign you were running. I've certainly had that happen, and from talking to other folks, I think it's pretty common.

The problem illustrated by the above scenario is two fold: 1) the players aren't giving the DM effective feedback on how to improve, and 2) the players aren't discussing among themselves how to more effectively play together. Remember that table top RPGs (even if they're played over G+ or Roll20) are social games, and everyone needs to be working together to achieve the result of fun being had. Working together, whether you're playing D&D, playing soccer or building software, requires regular feedback resulting in actionable info enabling continuous improvement.

So, how do we ensure we, as DMs, are making that happen? I like to do a short postmortem after every session, and a slightly bigger one after my group has hit certain milestones in the campaign. So, what's all this look like and what do we actually do?

The session postmortems are short, the idea being to just get some feedback about the adventure. Typically, I ask some questions and facilitate discussion. Remember the goal isn't to tell anyone anything, it's to get their opinions. If your players hit you with some weaksauce opinions like "It was good." then you'll need to dig deeper with more targeted questions.

Questions might look like this: (DM focused) "What did you all like about that session? What didn't you like? How could I have done better? (and more targeted) What did you think about how I set up that last combat? Did you think this NPC reacted reasonably to your actions? What do you think might happen now that you've done X?"

Milestone postmortems are a bit bigger, and I like to use them to get an idea of where the campaign is going, or to make design decisions. These might happen after a boss fight, or at the conclusion of a dungeon. My goal here is to find out how the players liked certain design or encounter elements, or how they feel the campaign is going. This is also a good place to ask what the players might want to do or explore next in the campaign.

Remember though the point isn't to get an answer and stop, but rather to get your players having an honest conversation about the game and their play together. If you're having trouble getting your players to give you honest feedback, the problem might not be them. Consider how you receive the feedback you do get. Do you argue or get defensive? If your players don't seem to want to tell you what they think, it might be because you don't take it well when they do. Keep your own reactions in mind as you seek to improve your game through this kind of discussion.

On treasure

When Hack & Slash wrote up his treasure table for OSR, she requested people using it give it a shout. So now I'm shouting.

My players ADORE this list. I've had them regularly ask me, as I describe a piece of abstract sculpture made of aluminium they just found in a dungeon hoard, "where are you coming UP with this stuff?" This is where: Treasure Tables. Containing quick and easy tables for creating everything from piles of trade goods to furniture to clothing and fine art, this will let you really spice up your parties' treasure hauls (with crates of spices!).

This pays big dividends in world realism as monsters and baddies suddenly have a wide variety of stuff to steal, all of which can be thematically appropriate to the bads themselves. My favorite function, however, is that varied kinds of treasure creates new challenges for the party to overcome. "How do we get all this freaking steel back to town?" "How can we find a buyer for this weird mindflayer art we found?" This basically allows treasure to CREATE adventures, instead of merely being the reward FOR adventures. That is fun stuff.

In short, I can't recommend this table highly enough.