One-Punch Man is a 3D arena fighting game in which players do battle using teams of three characters from the One-Punch Man universe.
The game features a unique “Hero Arrival” mechanic surrounding series main character, Saitama.
As in the manga and anime, Saitama is invincible to everyone except himself, and is so powerful that he can defeat anyone except himself in one hit.
However, if he is selected, he is always late to the fight, so he is not available for the first part of the fight, requiring the player to survive with only a two-character team until he gets there.
Certain moves and techniques can reduce the amount of time until Saitama arrives. If two Saitamas fight, they can deal damage to each other, but they will not flinch.
If Saitama is defeated (which can only happen at the hands of another Saitama), he runs off to go do something else instead of falling down.