Yellow Sign

The Yellow Sign is a fictional symbol or glyph, first described in Robert W. Chambers' book of horror short stories The King in Yellow (1895).

The King in Yellow never fully describes the shape and purpose of the Yellow Sign. Nonetheless, "The Repairer of Reputations", one of the stories in the collection, suggests that anyone who possesses, even by accident, a copy of the sign is susceptible to some form of insidious mind control, or possession, by the King in Yellow or one of his heirs. The stories also suggest that the original creator of the sign was not human and possibly came from a strange alternate dimension that contains an ominous and ancient city known as Carcosa.

H. P. Lovecraft and many of his imitators were great admirers of Chambers' book and incorporated many of his characters and symbols into their own works. In the latter-day Cthulhu Mythos, developed by August Derleth and other Lovecraft imitators, the Yellow Sign is the sign of Hastur and is used by members of his cult to identify one another. In addition, according to many of these works one of Hastur's avatars is known as the King in Yellow.

In 1989, Kevin Ross designed a Yellow Sign symbol for the Chaosium roleplaying game Call of Cthulhu. Ross created the symbol for an adventure scenario entitled "Tell Me, Have You Seen the Yellow Sign?" in the supplemental book The Great Old Ones. The symbol resembles a yellow triskelion, and is also believed to resemble a tentacled creature, since Hastur is often described as an aquatic tentacled being similar to Cthulhu.

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