Achilles' Heel. Like many mythological heroes, Achilles was part human and part supernatural being. His parents were Peleus, a king of Thessaly in northern Greece, and a sea nymph named Thetis. According to Homer, Thetis raised both Achilles and his closest friend and companion, Patroclus.
Other accounts added various details to Achilles' life. In one story, Thetis, fearful for her son's safety, tried to protect him by rubbing him with ambrosia, the food of the gods, and holding him in a fire to burn away his human weakness. This action horrified Peleus, and Thetis, angry at his distrust, abandoned her husband and child and returned to the sea.
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