Red Cap

A Red Cap or Redcap, also known as a powrie or dunter, is a type of malevolent murderous goblin, elf or fairy found in British folklore. They inhabit ruined castles found along the border between England and Scotland. Redcaps are said to murder travelers who stray into their homes and dye their hats with their victims' blood (from which they get their name). Indeed, redcaps must kill regularly, for if the blood staining their hats dries out, they die. Redcaps are very fast in spite of the heavy iron pikes they wield and the iron-shod boots they wear. Outrunning the buck-toothed little daemons is quite impossible; the only way to escape one is to quote a passage from the Bible. They lose a tooth on hearing it, which they leave behind.
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[Folklore] Red Cap is a thoroughly evil creature. He is a short, stocky old man with long gray hair and claws in stead of hands. He lives on the Scottish Border in ancient ruins of castles, especially in those with a bloody history of war and murder. He owes his name to the fact that he wears a red hat, which is colored by the blood of his victims. Red Cap moves with remarkable speed, despite the fact that he wears iron boots. He can overcome even the strongest man, unless the intended victim remembers to quote a few words from the Bible.

Goblin-like creature found in places where bloodshed has occurred. They lie in wait to bludgeon the lost.