After killing his family in an insane rage, Herakles (also known as Hercules) received orders from the oracle at Delphi to perform 12 labors to purge his sin. These were assigned by Eurystheus, king of Mycenae.
The king sent Herakles to Erymanthus to kill a wild boar that had terrorized the area. On his way he passed through the region of the centaurs. When one centaur, Pholus, offered our hero wine, the others grew jealous. A few centaurs are refined and steeped in learning. These were not. A great brawl erupted, Herakles defending himself with both his club and poisoned arrows.
Some took shelter in the house of Chiron. Herakles, in hot pursuit, shot Chiron with a poisoned arrow. One version of the story tells that Chiron, alone of all the centaurs, was immortal. He prayed to Zeus to remove this "gift," and release him from his pain. Zeus complied, and Chiron died. Herakles continued, mourning, to Erymanthus.
It was winter when he encountered the boar. Herakles drove it into deep snow, caught, bound it, and took it to Eurystheus. The king reacted to Herakles' success by hiding several days in his fortified room.
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