Known as the Father and Mother of All Monsters due to their numerous monstrous offspring, including the two-headed dog Orthrus, the Nemean Lion, the Hydra, the Chimera, and Cerberus. Typhon was the last son of Gaea and Tartarus, while Echidna's parentage is obscured by ancient sources; most often, she is listed as a daughter of Phorcys and Ceto. In the Theogony, Hesiod describes a climactic battle between Zeus and Typhon following Zeus' defeat of the Titans: Typhon rips out Zeus' sinews and is nearly victorious, but Hermes restores Zeus's sinews and Zeus finally overpowers the giant monster. Typhon was then trapped under Mount Etna, where he is believed to cause earthquakes and volcanic eruptions.