What if. Deku was reborn as a villain

Quirk Training

After receiving his new quirk, Izuku began his training under the guidance of All For One. The first thing he had to learn was how to control his powers. The quirk was incredibly powerful, but it was also dangerous. If he didn't learn to control it, he could accidentally hurt himself or others.

Izuku stood in front of All For One, ready to begin his training. The doctor was also present, monitoring Izuku's progress and taking notes.

"Today, we will be focusing on your quirk training. We need to understand the strengths and limitations of your quirk so that you can master it," All For One explained with a deep and eerie soothing voice.

"I'll be taking recordings and notes of your abilities. No, only they will be good data for researching but help you get a better understanding of your capabilities. So after each session, you can come to talk to me to look at the records or try some experiments on the scientific side of your quirk." Said the doctor from the sidelines

The first training session was intense. Izuku was put through a series of exercises to test the limits of his quirk. He practiced creating and manipulating the black smoke that his quirk produced, and he learned how to use it for offense and defense.

Over about two weeks, he learned how to increase the temperature of the smoke that he produced, creating a smokescreen for defense and offense. He also learned how to control the density and shape of the smoke, using it to create different forms and effects.

But Izuku was determined to become stronger. He knew that he needed to master his quirk if he was going to be successful in his revenge.

It wasn't until the beginning of his third week of training that the difficulty increased. The doctor slowly walked into the middle of Izuku training.

"Hello my assistant, I see that gotten used to your abilities right now." Said the doctor.

"Yes. No thanks to you and sensei. With your advice, I was able to get used to the quirk's transformation and figure out how to use it. But I must say, Am I going to do more experiments?" Said Izuku as he turned around.

"Why we're going to do something that will help the both of us," said the doctor with a little joyful chuckle.

That is when the footsteps can be heard from the dark hallway. At first, Izuku thought it person that was within the league but he pay more attention to the sound. It felt heavy and loud. As the sound gets louder, Izuku can hear some growls. It was then he saw the creature.

In front of Izuku where the creature with muscular physic, head exposing his brain, and scars showing around his joints and face. But it was eyes that got Izuku. The eyes look somehow blank but wild at the same time as if it was an undead beast.

"What the hell is that?!" Said Izuku trying to keep calm and hiding his shock.

"This is what I called a Nomu. These are my precious work. They are an artificial human, specifically created to help stop our enemies and testing on certain experiments." Said the doctor

"I see... so you want me to help you with it?" Said Izuku

"Yes since this one is still being developed and you are training. Why don't your spar with it? I already talk to All for One about it and he said that it is beneficial when you defeat it. You'll go to the next phase of your training." Said the doctor.

Izuku took a quick look at his potential training partner.
Analyzed the monster, studying its movements and weaknesses. He agrees with the doctor's proposal and the three walk to an open area.

"Here are the main rules. You can have multiple attempts to defeat the Nomu. When you are down, it is lost. You can come to me or AFO for any advice or help. When you defeat the Nomu, we can continue with the phase of your training." Said the doctor with his table in his hand.