The Silver-Eyed Hero

As I start my treatment on Midoriya using my vitality-infused mystic palm, forcing Izuku's body to absorb the bone fragments. All Might asks me a fair question.

"Uchiha-shōnen, won't you miss your next fight if you stay here healing Midoriya-shōnen?" (All Might)

That's a good point 

"Don't worry about it. I created a clone to take my place against Tokoyami." (Akira)

I actually created a shadow clone before entering the room. This will be enough to beat our bird-headed friend.

"I see. But isn't it a lack of respect for your classmate? I feel a bit bad for him for being defeated by a clone." (All Might)

I also feel a bit bitter about it, but I don't really have a choice here. It's that, or Izuku will be unable to fight his next match against Ida. I know very well that Ida is Izuku's friend, but he also sees All Might's successor as a rival of sorts. It wouldn't be nice of me to deny them this fight. It will be a valuable lesson for both.

Unfortunately for him, we all know that when Green Head gains access to the full power of OFA, he will leave everyone but me in the dust. Bakugo's last, power-up against AFO was just a plot armor device. There was only one OFA but also two AFO. In canon, they don't have 2 OFA-level fighters, so it was necessary to let the good guys in the end.

Now, with me in the picture, we have two top-level fighters.

"Hey young man! Something is happening to Midoriya!" (RG)

Recovery Girl's voice pulled me out of my thoughts. Indeed, Izuku's arm isn't healing like it was supposed to. Instead, red vein-like markings appeared on his body. A sign of OFA's activation. As if the quirk had a life of its own. Though it actually has a life on its own thanks to the vestiges. I noticed that this process began to suck Izuku's life force. I increased my life force output to match the sudden increase.

To my, recovery girl and All Might's surprise, his frail and yet muscular body transforms into a much more harmonious physique. His muscles grow a little bigger, his shoulders a little wider, and the rest of his body follows this growth. He now has a bulkier physique. He is clearly not as muscular as me, but definitely a little more the likes of Todoroki and Kaminari. On top of this, he has grown from 5,44 ft (ca. 166 m) to 5,54 ft (ca. 169 m).

When the treatment finished, his arm now healed and was better than before. All Might was the first to speak up.

"What happened?" (All Might)

"I don't know the ins and outs of this healing technique, so I can't say for sure." (Recovery Girl)

He is still too shocked to say more than that. As for what happened, I may have an idea.

"I may have an idea."

The two's gazes fell on me, waiting for me to explain this improbable scenario.

"All Might, did you train him Izuku intensely so that he could inherit OFA?" (Akira)

Judging by the look on Recovery Girl's face, she probably figured out what I wanted to say.

"Yes, but I don't see how it leads to this crazy situation. How can a treatment do something like this? How can his body change like this?" (All Might) 

His reaction is natural. After all, he is not even aware that OFA has a will. While we were discussing, Izuku finally woke up from his slumber.

"Where am I?" (Izuku)

"In your favorite spot: on a hospital bed." (Akira)

All Might and Recovery girls look at me with expressions that say "seriously". While the person in question only has a look of confusion.

"For some reason, I feel incredible, as if nothing were impossible!"

I looked down at his body in disbelief.

"What happened to me?!"

I would have the same reaction if I were him.

"Well, if you all could let me continue my explanation, it would be good because Ida already finished and won his match, and my clone is currently fighting Tokoyami." (Akira)

"S-sorry!" (Izuku)

Now that I have everyone's attention, I can finish this

"As I was saying, the fact that you developed your physique in such a short amount of time caused your muscles to heal incorrectly and incompletely, which hinders your growth and potential. So when I began treating your arm, OFA reacted to me infusing my life force to heal you and used it to fix your entire body by spreading it. In conclusion, my friend, you now have a trained body better than before that doesn't hinder your growth rate." 

The master and the apprentice seem really hyped by the news.

"How much do you think I can handle now?" (Izuku)

good question

"I'd say… about 10-15% without hindrance, 20% will hurt, and past that is still a bit much. At least, the stronger your body is, the less armed you will be if you ever need to go Plus Ultra." (Akira)

He still needs time to adjust to the increase in raw power, though. He won't be able to use it effectively for now. Better than that, without scars and permanent complications, he will become stronger than even the final power of his canon counterpart, which is pleasing.

Izuku is now so excited that he is almost metaphorically glowing.

"Anyway, Izuku, now that you are healed, you can join the others to watch Bakugo's match if you'd like. I have something to discuss with All Might. I advise you to return to the waiting room, though. Try to get a feel of your boost in power before your match against Ida. If the others question your physical changes, just say that my treatment helped your body adapt to your quirk."

He furiously nodded and left the infirmary; me and All Might also left soon after and stopped at a secluded corner.

"I think you understand what I want to say." (Akira)

"Indeed, I thought that OFA didn't have a will, but this unexpected twist makes me think otherwise." (All Might)

"In my opinion, more than just a will. I think the previous holders' consciousness may inhabit OFA through the vestiges."

All Might looked surprised, but soon seemed to recall something with a pensive expression.

"My master said something about the vestiges, she told me that a voice said "the time hasn't come yet" to her. I also had visions about those vestiges in my youth, but it was a one-time thing."

There was a moment of silence, like we were lost in our thoughts, but I have the answer.

"I noticed that after Izuku's change, the previous holder's signatures have grown stronger. So here is my theory: The "time" that your master mentioned might be the moment where the previous holders' consciousness in the quirk will fully awaken and be able to communicate." (Akira)

"Do you really think it's possible?" (All Might)

All Might says with an expression of disbelief and yet excitement. Probably at the idea of being able to communicate with his master, Shimura Nana.

"Not only that, but I think it also means that the previous holder's quirks might awaken along with the consciousnesses."

All Might seem even more confused

"Midoriya-shōnen might be able to awaken the previous users' quirks? This will be a lot for him to handle." (All Might)

All Might's PTSD of multi-quirk holders seems to trigger. I can't blame him, knowing how much he suffered at AFO's hands.

"In addition, because of the stockpiled raw power, I bet that these quirks will be far stronger than they originally were, and some aspects of their power might change. I suggest you investigate the previous users' so that we know what the quirks are and how to train them." (Akira)

he agreed to my suggestion.

"Indeed, it should be done. The only quirks I know are my master's quirk Float and her predecessor's Smokescreen. Smokescreen is self-explanatory; it can be released from the whole body and float; lets one levitate in the air."

I know that already, as with all the other quirks, but you don't need to know that.

"If we take the stockpiled power, then smokescreen will just have an increase in smoke amount. For float, however, I think we can expect it to change from levitation to straight high-speed flight. We still need to figure the others out."

All Might nods

"Indeed, I will share this with the principle as well. I greatly appreciate your help, Uchiha-shōnen. Now we need to regain our respective seats."

When he was about to turn back, I stopped him before returning to my class.

"One last thing, all Might. Considering what happened to your successor, I think it may be possible to use your embers with my treatment to heal you completely from your injury."

Indeed, Izuku's case showed that OFA's power, or at least Yoichi Shigaraki's original power in addition to transference, might be biological manipulation. It is further proven by All Might's muscle and small forms. So I can use this and use the embers as a catalyst to use my life force and regenerate his missing organs and any abnormal condition. Even if he loses his powers in the end. He deserves to live the rest of his life in peace after all he has done.

All Might seemed surprised by my statement. A sincere smile forms on his face, unlike his usual Symbol of Peace smile.

"Then I will place my hopes on you then."

He said as he left the hall.