Whenever SHIP: The Casanova starts its turn with 50 hit points or fewer, it is actively sinking and must make DC 10 Constitution saves every turn. If SHIP: The Casanova has 0 hit points, it automatically fails its saving throws to avoid sinking. On a failed save, one of the ships decks is completely filled with water. If all the decks are filled, the ship has sunk and drops to 0 hit points.

Repairing the ship so that it has more than 50 hit points stops the checks or saves but does not remove any water. If at least half of SHIP: The Casanova’s minimum crew spend an action bailing over two turns, they can restore a ship’s deck. Some magics may be able to remove water from a deck, at the DM’s discretion.