Cthugha was created by August Derleth in "The Dweller in Darkness" (1945). It manifests as an enormous living conflagration and is associated with the star Fomalhaut.
Within Derleth's elemental framework for the Mythos, Cthugha represents the fire principle. It is counted among the enemies of Nyarlathotep, and certain occult texts suggest it can be summoned as a counter-force against that entity.