Izuku thought he was quirkless however he did have a quurk. His quirk is called Power Of Will. If Izuku's will is strong enough it will prevent him from dieing and give all his stats a massive boost. However one day durring his training Izuku is hit by a massive ball of energy and his quirk not only saves him but ot also gives him a new power long thought to be nothing but a fairytail. Izuku obtains Ultra Instincts. With this power Izuku tries to get into U.A but since Ultra Instincts isn't a quick and no one knows about Power of Will (including Izuku) U.A turns him down. With out U.A how can Izuku become a hero. Wait Izuku doesn't want to be a hero he just wants to help people. So Izuku decides to become a Vigilant and help people that way.