Cerberus

It was the gigantic, three-headed hound of Hades, which guarded the gates of the Underworld and prevented the escape of the shades of the dead.

Heracles was sent to fetch Cerberus as one of his Twelve Labours, a task which he accomplished with the aid of the goddess Persephone.

Parents: Echidna and Typhon

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Heracles, wearing his characteristic lion-skin, club in right hand, leash in left, presenting a three-headed Cerberus, snakes coiling from his snouts, necks and front paws, to a frightened Eurystheus hiding in a giant pot. Caeretan hydria (c. 530 BC) from Caere.