Styx

Styx is a 3-headed hellhound owned by Lilith. He is an amalgam of 3 of Lilith's victims, but primarily controlled by the center head, Tony. After drinking a goblet of water from the river Styx, he is cursed to turn to stone if his collar is removed. The collar allows Lilith to call him to her simply by saying "heel" to conjur a leash of fire from her hand.