CEBERUS

Cerberus or Kerberos 

Herakles and Cerberus

(Greek: Κέρβερος) is in Greek mythology the hellhound that belongs to Hades and guards the entrance to the underworld, so that no dead out, while no living gets into it.

It is said that Cerberus has three heads. However, the number of its heads is controversial, as in some theories it is also 2, 50 or even 100. Furthermore, Cerberus' breath is deadly.

Family
Cerberus is the son of Echidna and Typhon. His siblings are the Chimera, the Hydra, the Nemean Lion and the Sphinx.

Story
Eurystheus once charged Herakles with kidnapping Cerberus to the Overworld. This was Heracles' twelfth job. Hades allowed Herakles to take Cerberus to the Overworld, so that he could bring him to Erystheus.