The Servitors of the Outer Gods are a fictional race created by Chaosium for the Call of Cthulhu RPG, which was based on August Derleth's The Lurker at the Threshold.
The Servitors of the Outer Gods are amorphous beings that resemble squids, frogs, and octopi which are constantly changing their shape and appearance. When needed they accompany the Outer Gods, though most of them are in Azathoth's court.
The music to which the Outer Gods dance to is made by these demonic drummers and flautists. On occasion they will aslo play for cultists to summon deities or to provide background music.