Ubb is the lord of the yuggs.
He is a large, aquatic, chthonian-like entity, pale gray and slug-like with a large mouth full of horn-like teeth, and ringed with tentacles. Ubb dwells in the cold fastness of the Pacific Ocean, with the rest of his race. The yuggs are said to guard their god, the Great Old One Zoth-Ommog, whose tomb, legend tells, lies at the bottom of an abyssal trench near the island of Ponape.