Hellhound

Hellhounds are a monster found in Doom 3 (better known as Pinky (Doom 3)), Doom RPG (a member of the Canine class), and Doom Eternal a creature summoned by Marauders.

Behind the scenes
The Hellhound is a monster intended to appear in Doom 64, and sadly, it didn't make it to the final cut. Its existing sculpture is that of a demonic canine with two heads, resembling the Greek mythogical Orthrus.