Myrtilus was the son of the messenger god Hermes and either an Amazon; Phaethusa, daughter of Danaus; or Clymene. He was the charioteer of King Oenomaus of Pisa.
Oenomaus wanted to avoid marrying his daughter Hippodamia, after he learned of a prophecy that his son-in-law would kill him. So, he organised chariot races between himself and any suitor that wanted to claim Hippodamia's hand. If the suitor won, he would marry her; otherwise, he would be killed. Many suitors had died in the hands of Oenomaus in this way, until Pelops, son of Tantalus, arrived.
Pelops and Hippodamia had already fallen in love, so they devised a plan. On the eve of the race, they approached Myrtilus asking for help; in return, he would spend one night with Hippodamia. Myrtilus accepted, and replaced the bronze linchpins of Oenomaus' chariot with ones made of wax. During the race, the linchpins broke and Oenomaus was dragged to death by his horses. Myrtilus then tried to claim his prize, but instead, Pelops killed him by throwing him from a cliff into the sea, an area that has since been named as the Myrtoan Sea in honour of Myrtilus. Just before he died though, Myrtilus cursed Pelops; this curse plagued many descendants of Pelops, including Atreus, Thyestes, Agamemnon, Menelaus, Aegisthus, Orestes and Chrysippus.
See Also: Hermes, Clymene, Oenomaus, Hippodamia, Pelops, Tantalus, Atreus, Thyestes, Agamemnon, Menelaus, Aegisthus, Orestes, Chrysippus