Ratman from the manga Ratman
Round 1 Hand to Hand
Shuto is in control but Kei knows that shuto is ratman
Round 2 hand to hand
Ratman is in control and kei thinks he is an alien
Shuto is in control and kei is allowed the black blade
Ratman is in control but has prior knowledge of what kei's weapon's do and kei is allowed to choose one weapon from the entire gantz arsenal.