In Scottish tales, the kelpie is a shape-shifting water spirit residing in Scotland’s waters. While there is some disagreement about exactly what it looks like, some folklore states the Kelpie is a demon that can assume human form while other folklore suggests it assumes the shape of a horse. What most of the stories seem to agree on is that Kelpies are not beings you would want to encounter. Many versions of their legend state they have a voracious appetite for human prey.