Z-one (pronounced Zone), is a cyborg who serves as the main antagonist of the Ark Cradle arc and the final antagonist of the Yu-Gi-Oh 5Ds anime. He is the founder of Iliaster and is defined by its members, or "The Ancient One". Along with Aporia, Antinomy, and Paradox, Z-one is effectively the central antagonist of Yu-Gi-Oh! 5Ds, being responsible for all of its other main antagonists in one way or another, as well as for the first Zero Reverse that split Satellite and New Domino City apart. He is from about 200 years after the present day events of Yu-Gi-Oh! 5D's.