In the western Highlands of Scotland there lives a type of vampiric fay that resembles an eel with nine eyes. It lives in bodies of water near roadways, although there have been sightings of it in Badenoch, Loch Tummel, and some streams in Argyll.

The burach-bhaoi lies in wait for a horse, with or without a rider, to pass near enough by so that it can strike out, wrapping itself around the animal’s feet. Then it pulls tight, dragging the horse, rider and all, into the water, where it will drown its prey before draining it dry of blood.

Source: Barber, Dictionary of Fabulous Beasts, 31; Covey, Beasts, 182; Dekirk, A Wizard’s Bestiary, 26; Rose, Giants, Monsters, and Dragons, 62; Spence, Magic Arts in Celtic Britain, 95