This will go over a few things i think would be nice to add to the game as siege weapon slots
1: Greek fire
this would be either some sorta flamethrower, or a pot of oil that is lit and dumped onto the enemy ship to catch it on fire, either way it’d be a weapon used along with your ram
(btw it has been around for a long time, invented at about 700 CE which is before the canonical time of durza’s world-destroying blast so it would probably be found in the dark sea)
2: Harpoon guns
These would pull in enemy ships, chance to escape like whirlpools do. tiers would be the same material as the mortars and would increase in pulling strength(speed). There would be 3 variants: light harpoon with less strength but fire faster, a normal harpoon with standard strength and speed, and a heavy harpoon with low projectile speed but high strength.btw yes there would be reload speed and a renamed version of fuse speed behaving like the cannons and mortars do.
3: Swivel cannon
this would basically just be a cannon mounted on a turret, it would probably be archaic or dragonfire as it’d probably be more experimental like the archaic mortar is