The Orichalcos God, or the Great Leviathan (4Kids dub), is a gigantic serpent creature who is behind all the events in Season 4 of Yu-Gi-Oh!, Waking the Dragons, and thus is the true and final antagonist (and the Bigger Bad) of the arc. He was empowered by the dreaded Orichalcos magic and he employed the Orichalcos Stones to take over the world. It was these stones that made Dartz of Atlantis turn evil and use the Orichalcos Stones and cards to seek out victims to steal souls from to feed the Orichalcos God.