This should be obvious

This is a canon scenario.

Heroes(including students) : Villains had attacked UA. Currently now trap at USJ with Class 1 A, now to face off against the villains. Try not to get hurt or die.

Villains disguised as heroes: Same as the students but try not to reveal yourself as a spy.

Villains: you attacked UA with other villains.

All Might finally came. Fortunate for theheroes and student, butbunofrtunate for villains.