Cerberus

Cerberus is the guard who watches over the entrance to the Greek Underworld to prevent the Dead from ever escaping and the Living from ever entering, and he is the offspring of Echidna. He is a three-headed dog (or hellhound) with a serpent's tail and the mane of snakes; furthermore, Cerberus is huge, loud, and terrifying with a set of sharp lion claws. He is a gluttonous creature which Aeneas' guide, Sibyl, uses to get past the frightening beast.
 * __ Cerberus __**