In Scotland, on the Orkney Islands, there is a vampiric fay known as nuckelavee. Described as looking like a skinless centaur, it has a piglike nose that snorts steam, an overly wide mouth, and one large bloodshot eye in the middle of its forehead, which is about three feet wide. Its body is covered in thick yellow veins that pump its black blood; its overly long arms almost drag the ground as it walks.

Nuckelavee are the bane to all animals, humans, and plants; they even cause their own particular disease, mortasheen. Should it breathe upon a person, he will begin to wither up and die. Nuckelavee cause droughts, epidemics, and have been known to drive herds of animals off cliffs and into the sea, where they live. In fact, any area of unexplained ruin or destruction is said to be their handiwork.

Nuckelavee are repelled by the smell of burning seaweed; oftentimes it was gathered and burnt as a precaution. Like all fay, they are repelled by iron, but nuckelavee are also repelled by fresh water and falling rain, and they cannot cross running water. During the summer months, they are locked away by Mither o’ the Sea, the Orcadian concept of Mother Nature.

Source: Cavendish, Powers of Evil, 230; Mack, Field Guide to Demons, 37-38; Marwick, Folklore of Orkney and Shetland, 22