Pegasus is a winged horse from Greek mythology. He was a son of Poseidon (who often took the form of a horse) and Medusa. In mythology, Pegasus is the steed of the famous hero Bellerophon. However modern adaptations feature him in relation to Perseus and various other heroes.
When Perseus slew the gorgon Medusa, her blood hit the ground and a winged horse sprung forth from the puddle of blood. Named Pegasus, the flying steed aided Bellephron in the slaying of the Chimera, before becoming the carrier of Zeus's thunderbolts. Later the steed would reappear on Paradise Island along with the Greek Sphinx and Chiron, as part of Wonder Woman's menagerie. His offspring would become the mounts for the Amazons, which they would use to bring down aircraft during the Amazonian war on America.
Pegasus is virtually immortal, incredible strong and fast, and can fly via his enormous wings.