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.
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