Final Fantasy X
Voice Actor: N/A
Omega existed some 700 years prior to the events of Final Fantasy X as a warrior monk. It's not know why, but Omega decided to rebel against the teachings of Yevon, and he was branded a traitor by Yevon. They exiled him off of Spira's mainland, and he was forced to seek refuge in some small islands that were relatively unknown.
These islands later became known as the Omega Ruins, which is where Omega lived the remaining years of his life and eventually died. However, because of the extreme level of hate he had towards Yevon, when he died he transformed into Omega Weapon, and also helped with the formation of Ultima Weapon.