In Greek mythology, Cerberus, often referred to as the hound of Hades, is a multi-headed dog that guards the gates of the Underworld to prevent the dead from leaving. He was the offspring of the monsters Echidna and Typhon, and was usually described as having three heads, a serpent for a tail, and snakes protruding from his body. Cerberus is primarily known for his capture by Heracles, the last of Heracles' twelve labours.
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 (Louvre E701).
Cerberus and Hades/Serapis. Heraklion Archaeological Museum, Crete, Greece.
Heracles, chain in left hand, his club laid aside, calms a two-headed Cerberus, which has a snake protruding from each of his heads, a mane down his necks and back, and a snake tail. Cerberus is emerging from a portico, which represents the palace of Hades in the underworld. Between them, a tree represents the sacred grove of Hades' wife Persephone. On the far left, Athena stands, left arm extended. Amphora (c. 525–510 BC) from Vulci (Louvre F204).
Athena, Heracles, and a two-headed Cerberus, with mane down his necks and back. Hermes (not shown in the photograph) stands to the left of Athena. An amphora (c. 575–525 BC) from Kameiros, Rhodes (Louvre A481).
In Greek mythology, Orthrus or Orthus was, according to the mythographer Apollodorus, a two-headed dog who guarded Geryon's cattle and was killed by Heracles. He was the offspring of the monsters Echidna and Typhon, and the brother of Cerberus, who was also a multi-headed guard dog.
A two-headed Orthrus, with snake tail, lying wounded at the feet of Heracles (left) and the three-bodied Geryon (right). Detail from a red-figure kylix by Euphronios, 550–500 BC, Staatliche Antikensammlungen (Munich 2620).
A two-headed Orthrus and a three-bodied Geryon. Attic black-figure neck amphora, by the Swing Painter, c. 550–500 BC (Paris, Cab. Med. 223).