Cthulhu

Cthulhu is a fictional cosmic entity created by writer H. P. Lovecraft and first introduced in the short story "The Call of Cthulhu", published in the American pulp magazine Weird Tales in 1928. Considered a Great Old One within the pantheon of Lovecraftian cosmic entities, the creature has since been featured in numerous popular culture references. Lovecraft depicts Cthulhu as a gigantic entity worshipped by cultists. Cthulhu's appearance is described as looking like an octopus, a dragon, and a caricature of human form. Its name was given to the Lovecraft-inspired universe where it and its fellow entities existed, the Cthulhu Mythos.

In "The Call of Cthulhu", H. P. Lovecraft describes a statue of Cthulhu as "A monster of vaguely anthropoid outline, but with an octopus-like head whose face was a mass of feelers, a scaly, rubbery-looking body, prodigious claws on hind and fore feet, and long, narrow wings behind."

Cthulhu hibernates within R'lyeh, an underwater city in the South Pacific. His worshippers chant "Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn"

Reference: Wikipedia