Theseus and Pirithous
Theseus's best friend was Pirithous, prince of the Lapiths. Pirithous had heard stories of Theseus's courage and strength in battle but wanted proof, so he rustled Theseus's herd of cattle and drove it from Marathon, and Theseus set out in pursuit. Pirithous took up his arms and the pair met to do battle, but were so impressed with each other they took an oath of friendship and joined the hunt for the Calydonian Boar. In Iliad I, Nestor numbers Pirithous and Theseus "of heroic fame" among an earlier generation of heroes of his youth, "the strongest men that Earth has bred, the strongest men against the strongest enemies, a savage mountain-dwelling tribe whom they utterly destroyed." No trace of such an oral tradition, which Homer's listeners would have recognized in Nestor's allusion, survived in literary epic. Later, Pirithous was preparing to marry Hippodamia. The centaurs were guests at the wedding feast, but got drunk and tried to abduct the women, including Hippodamia. The Lapiths won the ensuing battle.
In Ovid's Metamorphoses Theseus fights against and kills Eurytus, the "fiercest of all the fierce centaurs" at the wedding of Pirithous and Hippodamia.
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