It was the battle training of 1A vs 1B, everyone went in groups of 4 and fought against another group of 4 from 1B. It was the last match, you were with Deku, Uraraka, Mineta and Mina.

You were part of 1A, and you were nearby, along with Monoma, Shinso and Uraraka when a black whip like thing started spreading from Deku's arm. He seemed unable to control it, and it was causing damage.

Through the cameras, everyone was watching, concerned. Nobody knew what was happening. The teachers didn't know whether or not to stop it. Uraraka was trying to calm Deku down, and Shinso was trying to get him to respond so he could brain wash him and get him to stop.

You were focused on trying to dodge those black whip thingies, almost getting hit or grabbed multiple times before you actually did get grabbed and thrown across the training ground you were all on, far away from everyone else, blacked out from hitting yourself, and your head against a wall.

Deku was still trying to get that weird black whip thing under control, and Shinso amd Uraraka were trying to calm him down. The rest of your teammates, along with Shinso's teammates, were still fighting each other far away, unaware of what was happening.

After a second, almost on cue, the black whips disappeared. It was Aizawa erasing it. Uraraka was making Deku float so he wouldn't fall, since he was now unconscious.