In the not too distant future, mankind battles over O-Parts, relics from an ancient civilization. It takes a special kind of person to unlock the full potential of these remnants from the past, and a unique breed of humans known as O.P.T.s (or O-Parts Tacticians) become a force to be reckoned with. Unfortunately, O-Parts can be used for good or evil purposes.

As the Olympia tournament continues, Jio squares off against Ikaros to save Ruby. It seems like a fair fight, but Ikaros is not what he seems. Will Jio be able to handle his true form? Meanwhile, the Zenom Syndicate moves closer to completing the Reverse Kabbalah...and Cross arrives at Olympia to take his final revenge against Satan.

In the not too distant future, mankind battles over O-Parts, powerful relics from an ancient civilization. Jio is a young boy with a tragic past who only trusts one thing in the world: money. Little does he suspect that he is also a very powerful O-Parts Tactician (O.P.T.), and inside him sleeps a demon of incredible ferocity. With his partner, Ruby, Jio embarks on a dangerous quest to acquire as many O-Parts as he can.

Jio is a young boy with a tragic past who only trusts one thing in the world: money. Little does he suspect that he is actually a very powerful O.P.T., and inside him sleeps a demon of incredible ferocity. He meets up with a girl named Ruby, and together they decide to embark on a dangerous quest to discover as many O-Parts as they can. Will Jio help Ruby realize her dream of becoming a world famous treasure hunter? More importantly, will Ruby help Jio realize his dream of--world domination?!