Greek underworld his duty was to bring these souls to the underworld and no one would persuade him to do otherwise. Cerberus (Kerberos), or the "Hell-Hound", is Hades' massive multi-headed (usually three-headed) dog with some descriptions stating that it also has a snake-headed tail and snake heads on its back and as its mane. Born from Echidna and Typhon, Cerberus guards the gate that serves as the entrance of the underworld. Cerberus' duty is to prevent dead people from leaving the underworld. Heracles once borrowed Cerberus as the final part of the Labours of Heracles. Orpheus once soothed it to sleep with
Pluto (mythology) fera vota)", where fallen gladiators were human sacrifices to Dis and Charon received their souls as his payment, to the delight of the underworld Jove "(Iovis infernalis)". Medieval mythographies, written in Latin, continue the conflation of Greek and Roman deities begun by the ancient Roman themselves. Perhaps because the name Pluto was used in both traditions, it appears widely in these Latin sources for the classical ruler of the underworld, who is also seen as the double, ally, or adjunct to the figure in Christian mythology known variously as the Devil, Satan, or Lucifer. The classical underworld deities became casually