Hastur: The King in Yellow

3rd cosmic entity in the Lovecraftian series of creatures

Hastur "the Unspeakable" (also called Xastur and Asatur) is a Lovecraftian Primal god whose figure was notably praised by August Derleth, who considered him "the scion of Yog-Sothoth" and "Cthulhu's half-brother".

Contrary to what many believe, Hastur was not created by Lovecraft. Hastur was conceived by the writer Ambrose Bierce in his story Haîta the sheperd. Hastur's first appearance in The Mythos of Cthulhu was a mention in the tale The Whisperer in the Dark, the only story written by Lovecraft in which his name appears.