Tityus, a giant, the son of Zeus and Elara. When Leto gave birth to Zeus' children Artemis and Apollo, the jealous Hera sent Tityus against her. Zeus, or Leto's children defended her. Zeus (or Artemis with Apollo) struck Tityus with his thunderbolts (their arrows) and he fell into Underworld. The condemnation of Tityus resulted in 2 vultures and 2 snakes eating his liver, which regenerated continually. According to some authors this punishment came about because of the rape of Leto; according to others, it was retribution for his attempt to take possession of the Delphic Oracle.
See: Titian Tityus.