The One Punch Man arc titled “Monster Association” begins with a shocking introduction to a character who stands out as the most formidable antagonist in the entire storyline. Following this, in the battle between Saitama and Orochi, a mysterious figure has been hinted at, looming larger than anyone previously encountered: God.
This mysterious being is considered the ultimate antagonist that the heroes must confront. Notably, God serves as the source of the calamity faced by the monsters, making the final showdown with Saitama almost a certainty. However, a theory currently under discussion suggests that God may have many more hidden qualities than we initially thought, and if true, it could completely change our perception of the narrative.
God: A Version of Saitama from Another Dimension?

The Monster Association arc is the longest and most engaging arc of One Punch Man, featuring spectacular action scenes and beautifully crafted techniques. It also plays a crucial role in building the overall world of the story, particularly in establishing the main antagonistic characters.
The protagonist has been shown to possess formidable strength that is both terrifying and overwhelming. Just a single touch can transform an ordinary human into an entirely new level of threat. A prime example is Garou, who has undergone a transformation into a monster capable of matching Saitama’s strength for a period.
This illustrates God’s immense power, and it serves as a foundation for the shocking theory: God is a version of Saitama from a different universe or timeline. Although the current portrayal suggests that these two entities exist in the same dimension, this theory is far deeper than it appears.

The basis for this hypothesis stems from the fact that both entities represent an unprecedented level of power that no one can contest. Moreover, in the battles between the heroes and the Empty Void, the strength bestowed by God has been revealed to exist within One Punch Man. Therefore, it is possible that God is indeed a version of Saitama from another universe, which could explain the evil nature of this character. The potential bending of reality by God also aligns with the ability to alter reality through the immense power of Saitama.
If this theory proves true, God would be the ultimate pinnacle of Saitama’s power, an ability that has grown to an unimaginable level, allowing him to do anything he desires while also imparting a portion of that strength to others. This would make him the last antagonist symbolizing the narrative, as he would clearly represent the only being capable of challenging Saitama himself.
The Enigmatic Nature of the Theory

Although this theory is captivating, it currently relies heavily on speculation. The concept of another universe has been acknowledged within One Punch Man, which could further support this theory, but as of now, evidence is scarce.
Nonetheless, this potentiality cannot be dismissed, as the only entity who could possibly match Saitama is, indeed, Saitama himself. Furthermore, God’s power could represent the peak of Saitama’s strength, as his progression seems limitless. Despite the current lack of definitive proof for this theory, it could very well become a reality in the future.
Source: Gamerant