Labors of Hercules. The Twelve Labours of Heracles or Hercules are a series of episodes concerning a penance carried out by Heracles, the greatest of the Greek heroes, whose name was later romanised as Hercules.
   They were accomplished at the service of King Eurystheus. The episodes were later connected by a continuous narrative.
   The establishment of a fixed cycle of twelve labours was attributed by the Greeks to an epic poem, now lost, written by Peisander, dated about 600 BC. After Heracles killed his wife and children, he went to the oracle at Delphi. He prayed to the god Apollo for guidance.
   Heracles was told to serve the king of Mycenae, Eurystheus, for ten years. During this time, he is sent to perform a series of difficult feats, called labours.
   Driven mad by Hera, Heracles slew his sons by his wife Megara. After recovering his sanity, Heracles deeply regretted his actions; he was purified by King Thespius, then traveled to Delphi to inquire how he could atone for his actions. Pythia, the Oracle of Delphi, advised him to go to Tiryns and serve his cousin, King Eurystheus, for ten years, performing whatever labours Eurystheus might set him; in return, he would be rewarded with immortality. Heracles despaired at this, loathing to serve a man whom he knew to be far inferior to himself, yet fearing to oppose his father Zeus. Eventually, he placed himself at Eurystheus's disposal. Eurystheus orig
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