Bad/Synopsis

History
Metal Bat used to be a C-Class Rank 223 hero, but after impressing the Hero Association he moved up to S-Class. The association members offered to arrange anything he wishes, even weapons. Metal Bat then request a bat that never breaks and received his signature bat. He is then berated by his sister for not getting Sweet Mask's autograph.

Alien Conquerors Arc
Metal Bat attended the S-Class heroes meeting, where he openly complains on missing his younger sisters piano lesson. From there, he proceeded to fight alongside the other S-Class heroes against Melzargard. During their fight Metal Bat was smashing the monster flying head and managed to find and destroy a marble inside its head, killing the head. With the aid of Bang and others, they are able to destroy all the marbles inside of it and kill Melzargard.

After the fight was over, the spaceship above them began to crash down and thex escape toward the headquarters. When Sweet Mask arrives and demands and explanation, he and the heroes were met with criticism. Angered by his statements, Metal Bat threatens to start a fight with him, but before the tension can escalate, they are surprised by Metal Knight's arrival.

Monster Raid Arc
Metal Bat was tasked to protect Narinki, a sponsors of the Hero Association and his son Waganma at a sushi restaurant. He tells the child to not put the dishes that Waganma has finished back in the counter, but the child doesn't listen, much to Metal Bat's displeasure. Metal Bat soon receives a call from his sister; she asks if he can help her with her shopping bags, but declines, because he is on a mission. His sister starts crying and hangs up the call. After the call, Metal Bat feels a sudden shaking. Metal Bat rushes back to Nariki and finds that Junior Centipede has emerged from the ground with Venus Mantrap. Furthermore, Junior Centipede has grabbed Wagama. Before the monsters could grab him, Metal Bat grabs his coat and engages in a fight with the mysterious beings.

Metal Bat has just finished his fight with Junior Centipede and Human Bird Grass. Nariki and his child Wagama are delighted and wish to celebrate. However, Junior Centipede was still alive and praises Metal Bat for his strength, but still questions Metal Bat about how high he is in the food chain. Before Metal Bat could finish Junior Centipede off, Senior Centipede erupted from the ground. Senior Centipede forced Metal Bat, Nariki, and his son out of the restaurant. Outside, Rafflesidon emerged from the ground and started releasing sleeping gas. Nariki and Wagama immediately fall unconscious. Metal Bat is left to fight two Demon-level monsters. During the battle with Senior Centipede and Rafflesidon, Metal Bat temporarily came under the control of Rafflesidon's gas. When under the influence of the gas, Senior Centipede gave Metal Bat a beating. However, Metal Bat was eventually able to resist the influences of the gases and then completely escaped its influences after injuring his own head. After regaining control, Metal Bat proceeded to defeat Senior Centipede and Rafflesidon with one strike each. However, only after the monsters were defeated did Metal Bat remember that he had not asked for their motivations yet.

After the Demon-level monsters were defeated, B-Class and C-Class heroes, Pineapple and Mohican, arrive at the scene. Metal Bat asks them to bring the Nariki and Wagama to the hospital so that he could finally help his sister with her shopping bags. However, Elder Centipede emerges from the ground. The lower class heroes inform Metal Bat about the monster, stating that is previously wiped out a town and it is marked as a Dragon-level monster. Metal Bat tells the two other heroes to grab the sponsor and the sponsor's child and run, while he prepares to go all out. Metal Bat intercepts Elder Centipede when the monster is charging at Pineapple and Mohican, but his attack did not manage to even leave a scratch and is launched to a building by Elder Centipede. Metal Bat then interpreted that the monsters face is it's weak point. Metal Bat jumps onto Elder Centipede while Elder Centipede is chasing after two heroes. Before Elder Centipede is able to reach the two heroes, Metal Bat unleashes an attack on Elder Centipede's head. Elder Centipede then tries to shake Metal Bat off by maneuvering around the city. Metal Bat is then launched hundreds of meters across the city and encounters Garou, who proceeds to attack him. The Hero Organization later tries to contact him but is unable to do so, due to the fact that Garou is fighting him. He's able to hold back against Garou, who is now much stronger than before, due to his extensive training and is already able to see Metal Bat attack patterns and comments he's disappointed on being unable to witness Metal Bat at his best.

Metal Bat retaliates with an attack, but Garou manages to dodge it. Garou is surprised by Metal Bat's persistence despite Metal Bat's numerous injuries, but insists that Metal Bat is at his limit. Suddenly, Metal Bat rushes to Garou with incredible speed. Garou still manages to avoid Metal Bat's attacks and attempts to counterattack, but Garou's attack are no longer able to faze Metal Bat either. Garou asks Metal Bat for the reason for this sudden increase in physical strength and Metal Bat simply explains that it's fightin' spirit. Metal Bat tells Garou to hurry up with the fight because he still needs to take care of a monster. Garou throws a manhole cover at Metal Bat, but Metal Bat hits it back with his bat. However, Garou already managed to reach Metal Bat by the time Metal Bat followed through. To counter Garou's swift attack, Metal Bat tackled him and launched him toward the ricocheted flying manhole cover. Garou's manages to catch the cover, however. Metal Bat tells Garou to not be full of himself. Garou suddenly launches a barrage of attacks at Metal Bat. Metal Bat tries the take the offensive, but none of his attacks connect. Garou continues to mock Metal Bat, asking him if he's going to persist until he dies. Metal Bat retorts by saying he'll fight until he wins and proceeds to initiate a killing move. Unfortunately, Garou manages to repel the attack and launch a blow to Metal Bat's chest, leaving Metal Bat laying on the ground. Abruptly, someone shouts, "Big Brother!".

Metal Bat is about to land a powerful blow on Garou, but stops because his sister Zenko is there. Garou then punches Metal Bat, but before they could clash again, Zenko jumps right in front of Metal Bat, saying that Metal Bat made a promise not to fight while she's around. Garou gets angry, but respects their promise and leaves the fight to pursue for Watchdog Man.

After Zenko explains why she's there and remembers about the monsters, Metal Bat tries to meet Elder Centipede again, but Zenko hits him in the back of the head and Metal Bat falls on the floor unconscious, due to his exhaustion.

Super Fight Arc
An unconscious Metal Bat is later seen being taken to the hospital with Zenko watching with worry. When he wakes up, he is seen watching the news about Monster Association with Zenko.

Psychic Sisters Arc
He briefly appears to defeat a Dragon-level threat and is angry because he's missing his cat giving birth. He plans to take his frustrations out on the monster but said monster is destroyed by Tatsumaki and Saitama during their fight and attempts to calm himself down afterwards.