Toshinori Yagi & U.A. Students vs. League of Villains

Toshinori Yagi & U.A. Students vs. League of Villains is a battle fought between the Pro Hero All Might, alongside some students of Class 1-A, and the League of Villains members Tomura Shigaraki, Kurogiri, and Nomu.

Prologue
Just before Tomura and Nomu kill off Izuku, Tsuyu and Minoru, All Might arrives at the U.S.J. facility, telling everyone to have no fear since he is here. He declares that he knows the gist about the situation, because he had run into Tenya on his way to the U.S.J., which infuriates him. His anger grows when he sees that the students had a hard time and Thirteen and Shota were injured protecting them.

The last remaining Tomura's underlings are intimidated by his presence, and before they can react, All Might enters the central plaza in a flash, instantly defeating them and saving Shota. All Might apologizes to the heavily injured and unconscious Shota, then he turns his attention to Tomura. Using his super speed again, All Might rescues Izuku, Tsuyu, and Minoru, knocking Tomura's hand mask off. Then he tells the students to take Shota to safety.

Tomura feels agitated because his father's hand fell from his face, but when he puts it back on he feels more relaxed and in control. Tomura is surprised he was unable to defend himself but notes that, although All Might is really fast, he has still gotten slower. Izuku tells All Might his smash attack was ineffective on Nomu, but All Might claims he has everything under control and the students leave the area.

Battle
All Might rushes Tomura and attacks with a Carolina Smash, but Nomu intercepts him and absorbs the impact, much to All Might surprise. Nomu tries to grab him but he ducks and punches Nomu in the gut, but this attack has no effect as well. He punches Nomu two more times in the head and then retreats after realizing the strikes are not effective. Nomu charges at All Might and swings.

All Might evades and counterattacks with three more punches while Tomura arrogantly explains his attacks don't work Nomu's Shock Absorption Quirk, and that he would have a better chance of defeating him if the Nomu let him gouge out it's flesh. All Might thanks Tomura for revealing Nomu's weakness and then suplexes the monster, creating a large shockwave.

While carrying Eraser Head towards the exit, Minoru notices how strong All Might is and cheers him on. However, Izuku knows the truth about All Might's limit and worries he will overexert himself.

When the dust settles, All Might realizes that Kurogiri created a portal beneath them to save Nomu and trap All Might while he still remains in the suplex position. Nomu uses the opening to bury his claws into All Might's side, where he has his weak point, while Tomura mocks that his plan to bury Nomu in the concrete would not work as it was modified to have the same strength as him. All Might lets go of the Nomu's torso and tries to free himself from the monster's grip without success.

Kurogiri drags them both slowly inside the Warp Gate. Kurogiri explains Nomu had to restrain All Might because he's too fast, and now he plans to close the gate when All Might's halfway through to cut him in half. Seeing All Might in mortal danger, Izuku asks Tsuyu and Minoru to take care of Shota, rushes back to the fight.

Kurogiri intercepts him and prepares to use his warp gate on him, but Katsuki suddenly arrives and blasts Kurogiri before pinning him down. Shoto accompanies him and freezes Nomu, allowing All Might to break free of the villain's hold. Eijiro joins the fray as well, but Tomura evades his surprise attack.

Tomura condemns Kurogiri for allowing Katsuki to capture him. Katsuki reveals he figured out that Kurogiri uses the black mist to hide his actual body and he knows to aim for his neck armor. Kurogiri tries to move but Katsuki threatens to blow him up. Eijiro tells him that's something a true hero shouldn't say.

Tomura compliments the student's efforts and orders Nomu to free Kurogiri. Much to everyone's shock, Nomu breaks off its frozen limbs and regenerates them. Tomura explains that Nomu has more than one Quirk, including Super Regeneration, and explains that the Nomu has been modified to take All Might at 100%.

Nomu attacks Katsuki in order to free Kurogiri created a powerful shockwave that knocks down the students. Izuku thinks that Katsuki couldn't dodge that devastating strike, only to see him by his side. Izuku is surprised that he was fast enough to react to Nomu, but he replies he was not. When the smoke from All Might's attack clears, it shows that All Might saved Katsuki in time but took the brunt of Nomu's powerful attack.

After seeing All Might saving Katsuki, Tomura begins to monologue about the use violence to protect comrades, and how society categorizes such violence as good or bad depending on whether it is carried out by heroes or villains. He continues to say that the title "Symbol of Peace" is nothing more than an oppressive form of violence, accusing All Might of using the title to create more violence. All Might replies that his words are preposterous, as he only wants to use violence for fun. Tomura admits that he has figured him out.

The students agree to backup All Might because they have the villains outnumbered, but All Might tells them to leave instead despite their insistence, especially from Izuku who knows that his time limit is about to end. Tomura orders Kurogiri and Nomu to attack All Might while he deal with the students. The villains approach while All Might finds his resolve despite his declining power.

The Symbol of Peace comes to blows with Nomu, and the shockwaves produced by their fight keep Kurogiri, Tomura and the students from getting near them. All Might and Nomu fight head-on, trading punches at incredible speeds. Tomura reminds the hero about Nomu's Shock Absorption, and All Might replies that if the Quirk only absorb the shocks but doesn't nullified, there's a limit to it and keep punching.

The Nomu continues to strike back, and All Might says if it can withstand him at 100%, then he must go beyond his limits and starts to fight with everything he has. Nomu begins to get overwhelmed and gets sent flying across the stage. It recovers and jumps back at All Might forcing them to collide in mid-air. They continue to scuffle until All Might throws Nomu into the ground.

All Might swiftly lands, and as Nomu bounces off the ground, the Number One Hero tells him the meaning of Plus Ultra. He charges up one final smash and defeats Nomu by sending him flying through the roof and into the stratosphere with one final, powerful, and epic punch. The students watch in awe as All Might stands victorious, claiming that he truly have gotten weaker, because in his prime with five punches would have been enough but it took over three hundred mighty blows to defeat the villain.

Aftermath
Despite his victory, it has been very costly, and All Might has barely more time to maintain his muscular form plus he can't move, so he tries to bluff in order to scare Tomura and Kurogiri away. Frustrated, Tomura mulls over All Might's strength and believes All Might is still as strong as he has always been. All Might threatens Tomura in a bait to get the villains to flee. Believing All Might victorious, the students decide to return to their class. However, Izuku knows Nomu took too much out of All Might and he could revert to his weak form at any time.

Kurogiri reassures Tomura saying that All Might is really in bad shape by Nomu's attacks, that the underlings are beginning to recover as well, and that U.A. staff has not yet arrived, so if he and him work together they still have a chance to kill All Might despite Nomu's defeat. Tomura agrees with him and they both attack the defenseless All Might.

The hero begins to panic, but then Izuku appears. He use his Quirk to move at blinding speeds and intercept the villains. He prepares to use a smash on Kurogiri's weak point, but he creates a portal for Tomura to stick his hand through and the latter goes to destroy Izuku's face. Before he can use his Quirk, a bullet flies through Tomura's hand, saving Izuku. They are all saved when Tenya returns to the U.S.J. with the U.A. faculty as back up.