One Punch Man Season 2 Episode 4 revealed that Garou already hated the heroes even when he was still a kid. It started while he was watching a television program that featured Justice Man. Garou was wondering why Justice Man always wins in the end, saying that monsters also deserve the spotlight and have reasons why they fight. During that moment, Garou vowed to be the strongest monster that no one can defeat.
One Punch Man Season 2 Episode 4 also showed the meeting of the board members of the Hero Association regarding what happened to Director Zeimeet. They have a belief that Garou isn’t only targeting heroes, but also the people who run the Hero Association. To prevent such incidents from happening again, the Hero Association ordered their executives to stay in their house, and if they go out, they must be accompanied by at least one Class-S hero.
The Hero Association first contacted King, a Class-S Rank 7 hero who is considered as the “Strongest Man on Earth.” King refused to serve as a bodyguard for the Hero Association executive, saying that he’s currently in the middle of a battle. Meanwhile, Class-Rank 15 hero Metal Bat was left with no choice but to guard an executive and his son who just wanted to try “peasant foods.”
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Everything seemed to be fine when they entered the restaurant but after a few minutes, two monsters appeared and tried to kidnap the executive and his son. As expected, Metal Bat easily defeated the two monsters as well as the two other reinforcements who came after them. The Hero Association, who is secretly watching in their headquarters, praised Metal Bat for saving the executive. However, they suddenly remembered what happened two years ago when a Dragon-level threat who has the ability to level the surface appeared.
One Punch Man Season 2 Episode 4 revealed that the Hero Association was talking about Centichoro, a giant bug monster. Metal Bat decided to deal with the monster by himself, ordering the two Class-C heroes beside him to bring the executive and his son to safety. Metal Bat attacked the monster as hard as he could, but it didn’t take any damage at all. Metal Bat immediately realized that the monster’s weakness is its face.
However, despite hitting it multiple times with his special technique, Metal Bat was still unable to completely defeat the monster. To make things more complicated, the “hero hunter” Garou arrived in the area to eliminate Metal Bat himself. The final scenes of One Punch Man Season 2 Episode 4 showed Metal Bat and Garou preparing for an intense battle while Centichoro is destroying City S.