One Punch Man - The Strongest is an action role-playing game based on the Japanese manga series of the same name. In the game, a hero named Saitama becomes the world's strongest man after receiving a mysterious power, allowing him to fight and defeat enemies with a single punch. The power is later revealed to be a combination of several elements, including strength, stamina, and bone density.

The gameplay is divided into several modes, including story mode, wherein the player controls Saitama, and fights the enemies of the series. In addition, there are several modes wherein the player can fight alongside the other heroes of the series, or can fight against them.