Zvilpogghua is known to the American Indians as Ossadagowah and is mentioned under this name in the book Of Evill Sorceries Done in New England of Demons in No Humane Shape. He usually takes the form of an armless, winged, bipedal toad with a long, rubbery neck and a face completely covered in tentacles. He currently dwells on Yrautrom, a planet that orbits the star Algol, in the Perseus Constellation. Zvilpoggua is an alternative spelling.
“The Star Beast” is the avatar form of this god (sometimes called the minion of “the Great Old One”) and was sometimes summoned by the American Indians, although they rarely did this because it could only go back to the stars of its own free will.
Zvilpaggua was created by Clark Ashton Smith, but not elaborated upon. August Derleth using H.P. Lovecraft's unfinished work developed Zvilpoggua in "The Lurker at the Threshold".