Kerberos (Cerberus)
The Underworld was the realm of the dead and was ruled by Hades (Pluto) and his wife, Persephone. Kerberos (Cerberus) guarded the entrance to the Underworld and kept the living from entering the world of the dead and devouring those who tried to escape. Kerberos' father was Typhon, a huge dragon-like monster with 100 necks on each of which was a dragon head belching flame. His mother Echidna was half woman half speckled serpent. According to most sources, Kerberos, was a three-headed, dragon-tailed (or serpent-tailed) dog, with innumerable snake heads on his back. According to Horace, Kerberos possessed one hundred heads while Hesiod stated he had fifty. The centre head was that of a lion, while the others were that of a dog and a wolf. Kerberos was fierce, pitiless, and flesh-eating. The poison used in Medea's attempt to murder Theseus was made from Kerberos's drool.
Kerberos was overcome four times.
Herakles' twelfth and final labour was the most dangerous one. King Eurystheus ordered Herakles to go to the Underworld and kidnap Kerberos. Heracles went to Eleusis to be initiated into the Eleusinian mysteries, to absolve himself of guilt for killing the centaurs and to learn how to enter and exit the underworld alive. He journeyed there and back with the aid of Athena and Hermes. Herakles asked Hades for permission to take Kerberos. Hades agreed as long as Herakles overpowered the beast without using his arrows or his club.
Herakles found Kerberos and wrestled the beast into submission, despite the dragon in the tail of the fierce flesh-eating guard dog biting him. Herakles grabbed Kerberos by the throat and dragged him to Mycenae through a crack in the surface of the earth. After this, Herakles dispatched Kerberos to guard one of the secret groves of Demeter but the dog eventually made his way back to the Underworld where he resumed guarding the entrance.
The poet and singer Orpheus journeyed to the Underworld in search of his lover, Eurydice. Orpheus lulled Kerberos to sleep by playing his lyre, and managed to sneak past.
In Roman mythology (Virgil's "Aeneid"), the Trojan prince Aeneas descended to Tartarus to visit his father Anchises. He was escorted by the Sybil of Cumae, who threw Kerberos a cake seasoned with honey and poppy seeds. Aeneas was then able to sneak past.
Also in Roman mythology, Psyche similarly lulled Kerberos to sleep with drugged honeycakes.
Ancient Greeks and Romans placed a coin and a small cake in the hands of their deceased. The coin was meant as payment for Charon the ferryman over the river Styx, and the cake helped to pacify Kerberos.
