KERBEROS (or Cerberus) was the gigantic hound which guarded the gates of Haides. He was posted to prevent ghosts of the dead from leaving the underworld. Kerberos was described as a three-headed dog with a serpent’s tail, a mane of snakes, and a lion’s claws. Some say he had fifty heads, though this number might have included the heads of his serpentine mane.
Herakles was sent to fetch Kerberos forth from the underworld as one of his twelve labours, a task which he accomplished through the grace of Persephone.
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