Nereid
About
Fifty daughters of the old sea, and any one of them can flatten a swell or raise one. They keep company with sailors more often than with anyone else and are generally well disposed toward them, which is exactly why the ones who are not well disposed are so dangerous. A nereid does not need to attack a ship. She only has to stop helping it, at the wrong moment, in the wrong water.
Stats
Save Rolls
Traits
Special Attack
Raise the Swell: 60 ft, save Dex Quick, fail save roll 1d6+2 bludgeoning as the water heaves; creatures aboard a small vessel are put over the side, cooldown 3 rounds. Riptide: bludgeoning, melee 10 ft, +2 to hit, 1d6+2.
Special Defense
Calm the Water: as an action she can flatten the sea within 100 ft, ending storm and swell effects entirely. She will do this for a vessel that has treated the sea well, and pointedly not for one that has not. Of the Deep: she cannot drown, cannot be held underwater to any effect, and swims faster than any ship sails.