This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Duergar (English)
The Simonside Dwarfs, also known as Brownmen, Bogles and Duergar, are in English folklore a race of dwarfs, particularly associated with the Simonside Hills of Northumberland, in northern England. In F. Grice's telling of the traditional story The Duergar in Folk Tales of the North Country, one of them is described as being short, wearing a lambskin coat, moleskin trousers and shoes, and a hat made of moss stuck with a feather.
The legendary dwarfs of Simonside were mentioned in the local newspaper, the Morpeth Gazette, in 1889, and in Tyndale's Legends and Folklore of Northumbria, 1930. They delighted in leading travellers astray, especially after dark, often carrying lighted torches to lead them into bogs, rather like a Will-o'-the-wisp. The menacing creatures would often disappear at dawn.