Class 1-A vs. Toshinori Yagi

Class 1-A vs. All Might is the battle fought between Class 1-A and the hero All Might, disguised as a villain.

Prologue
After the attack on the League of Villains, students in class 1-A return to U.S.J. to carry out rescue training under the supervision of Shota Aizawa and Thirtee, both in the process of recovering their injuries from the previous attack. What the students don't know is, before the training began, All Might told Shota that he wanted to add a surprise to the training, acting like a villain.

Shota replied that he was against the idea because the students had just experienced a villain attack, and All Might’s idea may traumatize them if it goes wrong. All Might replies that they must teach the students determination to overcome it, and teach them that they should always be prepared as heroes to face any threat. All Might eventually convinced Shota to let him add the surprise, but that it was to be his responsibility.

After carrying out rescue practices in the cliffside, the class moves to the urban area of the U.S.J. for another training, which involves of four students acting as rescuers, searching and helping their classmates in need of rescue scattered in unknown locations in unknown conditions. Thirteen selects Izuku, Ochaco, Katsuki and Minoru Mineta as the rescuers.

As the training starts, Katsuki blows himself away from the starting area in search of the victims. The remaining three agree to split up and search for the victims who are able to speak. Sitting in hiding, Shoto meets All Might, whom he does not recognize when disguised as a villain. Believing he is facing a true villain, Shoto uses an ice attack against All Might, who dodges the attack and uncovers himself to reassure Shoto. Then All Might explains him his plan and ask to play along instead, acting as if he had been subdued by a villain. Shoto accepts.