Saitama's origins are well known, at least as far as he chose to become stronger. There are still many dark spots on the protagonist of One punch manbut what is certain is that he has a strength capable of overcoming anyone, even without making a particular effort.
It has now been several chapters since Saitama and Tatsumaki fought. The two heroes faced each other, but the battle is in the final stages One Punch Man 182. Everyone tries to understand what causes that exaggerated tremor to panic among the heroes as Saitama is thrown back toward the fortress, only to start right back up, leaving the hero who was watching the scene stunned.
Tatsumaki has now used almost all of his power, convinced that apart from the sensational enemies with whom she has faced life and death fights, there is none who can stand up to her. To do this, he tries some finishing attacks, with Saitama becoming increasingly difficult to control. Despite an earth tide swamping him, the hero of One-Punch Man is still unharmed, having nullified all effects of Saitama's attacks in one punch.
At this moment, Tatsumaki begins to remember his past, from her loneliness to Blast's hint, but also to the time she tried to save Fubuki from the Tsukuyomi organization, sparking her sister's resentment. In the end, Tatsumaki awakens, and Saitama therefore wins, who scolds but also encourages her. Eventually, Fubuki and his men arrive there, the latter managing to remain in their lady's service. And so this One-Punch Man battle that has left more than one person wondering about Saitama's true strength seems to be over.
