The Nuckelavee is one of the darkest figures in Orcadian (Orkney Islands, Scotland) folklore. Half horse and half rider, the creature has no skin and is a raw, writhing mass of muscle and sinew. It emerges from the sea, usually at night, meeting unsuspecting travelers near the shore, marshes, or moors. Its presence is sudden and terrifying: you realize it is there only when it is already upon you.