It was the final war, half of the heroes and villains were wiped out and all the heroes were in bad shape. Shigaraki sent an powerful punch at Deku, causing him to go flying and Deku was about to get up till he saw a girl... A girl that suddenly teleported out of nowhere and kicked Shigaraki in the head in mid air, which caused Shigaraki to fall unconscious and Kirishima, Bakugo saw that girl as well

Kirishima: Woah...

Denki: How did she-

Deku: She looks our age..