Ship-to-Ship Combat
Source: Astral Adventurer’s Guide p. 24
The following rules are designed to make ship-to-ship combat simple yet exciting.
Starting Distance
At the start of an engagement, the DM decides how far a ship is from its enemies. Three possibilities are provided in the Starting Encounter Distance table. The shorter the distance, the less time crews have to load weapons and make other preparations.
Starting Encounter Distance
| Distance | Notes |
|---|---|
| 250 feet | Long range for ballistae, mangonels, shortbows, longbows, light crossbows, and heavy crossbows |
| 500 feet | Long range for longbows and mangonels; beyond the range of ballistae and crossbows |
| 1,000 feet | Beyond the range of most ranged weapons |
| ^starting-encounter-distance |
Initiative
The “Dungeon Master’s Guide” presents a variant rule called Side Initiative, which is ideal for ship-to-ship engagements, since it saves you the trouble of tracking initiative for individual creatures aboard each ship.
Shipboard Weapons
A spelljamming ship typically has one or more shipboard weapons, ballistae and mangonels being the most common. Such weapons are slow to load and fire. Player characters are almost always better off using their own weapons and spells in ship-to-ship combat, reserving shipboard weapons for targets that are too far away to be damaged by other means.
Moving and Steering a Ship
A spelljammer can use a ship’s spelljamming helm to move and steer the ship without expending their own actions or movement. On their turn, the spelljammer determines how far the ship moves (up to its maximum speed) and decides whether to approach another ship or put more distance between the two.
On its turn, a ship can be turned and reoriented so that all its weapons can aim and fire at any target within range, regardless of where they’re situated on the deck.
Boarding
When one ship moves to within 5 feet of another ship, the spelljammer or pilot of the moving ship can maneuver it alongside the other ship, enabling creatures to move safely from one ship’s deck to the other ship’s deck until one of the ships pulls away from the other.
A ship that has enough movement can pull alongside another vessel, deploy a boarding party, and then move away, provided the members of the boarding party took the Ready action to position themselves so they can move onto the other vessel when it’s close enough.