After you defeated some invaders and completed your first test you saw tons of fireworks and then got teleported to the last defence academy with 16 other students and you weren’t in your class armor anymore. As you learnt more about the new people you suddenly heard a familiar voice and it was…sirei.

Sirei: "alright soldiers, welcome to last defence academy you were all chosen to save humanity for world death, and if you destroy me the bomb inside you will blow up killing ya."

after sirei said that he left and then…an alarm went off alerting school invaders at the ground.