CERBERUS
Cerberus or Kerberos in Greek and Roman mythology is a dog-like creature (usually) depicted with a three-headed guard who guards the gates of the Underworld, to prevent anyone who has crossed the Styx River to escape. Cerberus is found in many ancient Roman and Greek literature and architecture as well as modern, although Cerberus's depictions and backgrounds often differ according to the age of manufacture.
Cerberus is the son of Echidna, the half-human half-slave woman of a snake and Typhon, the great monster feared by the Gods. Cerberus is said to be related to Hydra Lernaea, Orthos and Chimera. The general description of Cerberus in Greek mythology and culture, has three heads mentioned each has its own capabilities; one head is able to see the past, one's head is able to see what is happening now, and one other head is able to see the future.
although from other sources the three heads represent the birth, life and death. Cerberus will only eat fresh meat, whether from humans, animals, or Gods, and freely allow dead spirits to enter the Underworld. In addition to guarding the gates of the Underworld, Cerberus also pet Hades who are very faithful to guard it.
Capturing Cerberus without weapons is the last task for Heracles given King Eurytheus after his son was killed by Megara after he was made insane by Hera. And anyway, his job is very difficult and dangerous. After taking the assignment, Heracles goes to Eleusis to begin from within Eleusis Mysteries so Heracles can learn how to enter and exit the Underworld alive and through the Centaurs of assassins.
Eventually Heracles found a way to enter the Underworld in Tanaerum with the help of Athena and Hermes showing the way. He passes Charon with the help of Hestia though hard-earned. Upon reaching the Underworld, Heracles meets Theseus and Pirithous. Two friends are punished and imprisoned by Hades for his attempts to kidnap Persephone.
One tradition tells, Heracles meets both of them with the circumstances of the legs being wrapped by many snakes that have turned into stone; another tradition mentions that both are seated on a chair that makes them lose their memory. First Heracles pulls Thesseus out of his chair but can not because his legs are trapped in his chair and when Heracles tries to free Pirithous, the earth suddenly shakes violently refusing to free him so Heracles leaves him.
After leaving both, Heracles meets with Hades and asks permission to bring Cerberus to the surface. Hades gave Heracles permission, but with a condition, Heracles had to drive Cerberus without using any weapons. Apparently Heracles was able to conquer Cerberus and drive it from behind Cerberus's back through the Peloponnese cave and take it to Eurystheus. The terrified King with Cerberus coming into the kingdom immediately ascended to Pithos and told Heracles to bring him back to the Underworld and free Heracles in return.
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