I was thinking, players with depth strider III, aqua affinity, and respiration III can be a real pain to keep away from ships if they go underwater since arrows will only travel a short distance before slowing down if you try to shoot a player from it. When they are above water your can manage them with a punch II bow, when they are on your ship you can either outnumber the enemy, or knock them off with a knockback II sword. However when the enemy is underwater in order to prevent them from either: wrecking your hull, following your ship back to your base or ship containment area, regenerating and delivering more arrows. You need to jump in the water and leave your ship, which is annoying and not the best thing to do in the middle of a ship battle. So I propose a solution, anti-personnel depth charges. The technology of the depth charge would be totally capable for this time period, a bomb with a timer attached to a weight. It could be hand dropped into the water or dropped from a crane I don’t really care, but the explosion underwater in real life would deliver a pressure shock wave to all the people in the water and cause their organs to pop like a balloon resulting in a quick and probably painful death. The depth charge would do a lot of damage due to the way it hurts people. It would discourage swimming in the water to get nearby a ship and encourage a lot more travel by a ship to get to another ship, cannon fights, and on deck swash buckling!!! (I would say arg but I myself am not much of any pirate, that is if pirates even actually said arg.)