Katsuki had died in the war, he had awakened his quirk and managed to outmatch Shigaraki's speed, but he was just too strong. Izuku arrived just when he died, he fought with Shigaraki but there was another big threat, All For One.

Katsuki was being revived by Edgeshot, but Katsuki revived by his own will, he woke up and even if he was told to stay still and not make any movements, he went to fight AFO, who was about to kill All Might.

He saved All Might, placed him far away from the villain.

"I thought we were fighting All For One? Who is this guy? I'll kill him!"

He yelled, All Might had to tell him that was AFO, but using Rewind to Rewind his body years back when he received damage.

Katsuki was full of sweat and pain, that actually made him stronger. He smashed himself against buildings, laughing like a maniac. He reached All For One and made a giant explosion, creating a big hole and making the villain be all in the bottom of it.

All For One seemed to have random flashbacks and yelled:

"This is all your fault, Kudo!"

Katsuki simply grinned even more.

"Have you finally gone senile, idiot! The name's Kacchan Bakugo!"