Joint Training Battle

The Joint Training Battle is a combat training exercise that pits the students Class 1-A against Class 1-B in a series of five team matches. This exercise is also used to examine Hitoshi Shinso's potential for the hero course. This is the first event to take place in the winter of the student's first year.

Prologue
Following the day after the Provisional Hero License Exam

Eraser Head and Vlad King hold a Joint Training Battle between their classes during the early days of winter. Each class dons their winter hero costumes and meets at Ground Gamma.

Class 1-B arrives after Class 1-A and Neito Monoma openly challenges Class 1-A to this decisive battle between the rival classes. He even reveals that students voted 1-B's play over 1-A's musical performance from the School Festival.

Eraser Head silences Neito and announces that there will be a guest for this exercise. Hitoshi Shinso is being reviewed for consideration into the Hero Course. Hitoshi re-introduces himself to everyone and explains that in order to become a great hero, he must overcome everyone else.

Vlad King and Eraser Head begin the exercise immediately afterward. Each class chooses lots to split into five teams of four. Each team battles one match at a time inside the training field. Hitoshi is placed on a team with both classes, making two matches are five against four. Each team perceives the other as villains and must try to capture one another.

The team that captures four people and places them inside an "Irredeemable Jail Cell" wins. Teams of five still lose if four of their members are jailed. Teams start at their own bases and the matches are set with a twenty-minute time limit. If time runs out, the team with the most captured enemies wins.

All Might and Midnight come to spectate the battle. The matches begin shortly after both all students draw lots to decide their teams.

Aftermath
Midnight reveals that Class 1-A won the battle overall and the winners celebrate their victory, leaving the losing class to lament over their loss.

Hitoshi Shinso reveals to Eraser Head and Vlad King that he knew the entire battle was serving his entrance exam for the Hero Department, also saying that he was disappointed in his performance and the fact that he lacked the strength to capture anyone.

Eraser Head questions Izuku Midoriya about the new move he used and Izuku claims that he isn’t sure what it was, describing how his power overflowed and saying that he didn’t know why the tendrils suddenly appeared. He thanks Hitoshi and Ochaco Uraraka for saving him, Mina Ashido also commenting on how tightly the latter grabbed him to help him, which leaves both Ochaco and Izuku embarrassed.

Hitoshi says that he didn’t save Izuku out of kindness, instead just wanting a rematch with his rival, and Eraser Head scolds him, and after a short lecture from Eraser Head, Vlad King then announces to Hitoshi that he will be joining the Hero Department starting from his second year.

Trivia

 * This exercise was first mentioned the day after the first-years Provisional Hero License Exam, by Pony Tsunotori of Class 1-B.