The kelpie is a mass of animated seaweed that can change its form at will. It lives to drown the foolish, and usually target humanoid males to devour. Males who are led into believing the kelpie is a woman not near water are led to a suitable location near the kelpie's home. If a humanoid is found near their lair, the kelpie only has to convince the male to come into the water and embrace the kelpie. Afterwards, the kelpie wraps itself around the charmed victim while dragging them underwater.