Izuku has always been a curious boy, wanting to know everything that he can, with no cares about how he learns it. Now, after the death of his mother has driven him into insanity, he has decided that nothing will stop him from learning everything th...
Just as Izuku moves to incapacitate another student and extract their blood, something slams into the door of the USJ, causing it to go flying and slam into him, blowing him away.
"Students! Are you all right!?" All Might demands, coming through the place where the door used to be with a concerned look on his face, much to the relief of all of the students, sans Todoroki, who is unconscious and quickly bleeding out.
"All Might!" Momo yells, running up to him. "Most of us are fine, but there are some injuries. Mine, Thirteen's, and Todoroki's are the most severe. My arms are paralyzed because of severed nerves, if Dr. Deku is to be believed, Todoroki was slashed across the chest by an oddly shaped sword, and Thirteen was wounded by her own quirk."
All Might frowns. "Bakugo, cauterize Todoroki's wound. Uraraka, use your quirk on Thirteen and Todoroki. Once you two are done, all of you evacuate, taking them with you. Once you get far enough away for signal to return, call the school about the situation and inform Recovery Girl that there are people in need of immediate medical attention if you can." He orders, before turning to face the Plaza, where Dr. Deku can be seen leaving through a portal to his lab, missing an arm, which is quickly regenerating.
————————————
Once the portal closes, Izuku slips off his lab coat and his suit. "Mavis, it's time to test out The Annihilator." He says.
"Understood." The AI says through the room's speakers, before the wall opens up revealing a mechanical suit, which Izuku quickly puts on.
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
"Now then. Mavis, open the return portal." He says, his voice warped by his mask.
————————————
"WHERE THE HELL DID YOU GO!?" Tomura demands. "ALL MIGHT ALREADY FINISHED CAPTURING ALL OF THE TRASH-TIER GOONS THAT WE BROUGHT!!"
Izuku waves him off. "I've been gone for less than 2 minutes, calm down. I was just getting prepared to fight him."
Tomura raises an eyebrow, his confusion overpowering his rage. "What? Why? I thought that Nomu was supposed to fight All Might.
Izuku shakes his head. "No, no, you misunderstand. The Nomu is my bonus for doing this job. It was brought along rather than being sent straight to my lab because the stipulation for me receiving it is that I have to face All Might one on one. Now, stand back and let me do my job." He explains, before walking toward All Might. "I appreciate you standing there and allowing us to talk, All Might." He says, causing All Might to grin.
"No need to worry about it, young man." All Might says. "I figured that it would be rude to interrupt. Besides," he cracks his knuckles as his grin is replaced by a scowl, "you crippled one of my students. This is personal now."
Izuku shrugs. "To you, maybe. To me, this is just me doing my job. Scientific innovation, especially on the level that I work at, is not cheap. Gotta make ends meet somehow, and it just so happens that All For One pays well. Besides, she'll be fine if she gets the right treatment." He says casually, though All Might doesn't hear the last sentence, having gotten caught up on Izuku's mention of All For One. Which leaves him open for Izuku's first attack, launched entirely without announcement.
Izuku dashes forward at top speed and slams his fist into All Might's face, breaking his nose.
All Might stumbles backward, surprised by the sudden pain, before steeling himself and retaliating, delivering a blow to Izuku's chest, which does no damage, shocking him.
"Allow me to let you in on a little secret, All Might." Izuku says, returning the blow and sending the hero flying. "This suit was specifically designed to fight you. It absorbs any kinetic energy that impacts it, nullifying melee attacks, and any damage it takes is automatically repaired by the nanomachines built into it. As for what it does with the kinetic energy it absorbs, well, I'm sure you can guess that." He explains.
All Might groans as he pulls himself out of the staircase that he had crashed into. "It's not shock absorption, it's shock redirection. It uses all of that stored kinetic energy to deliver blows of equal power to what it received. By fighting you, I'm essentially fighting a smaller, though no less powerful, version of myself."
Izuku grins under his mask. "Exactly! I knew you would understand!" He exclaims. "Now then, enough talk. It's time for the fight of the decade!"
All Might laughs, before the Hero and the Scientist dash toward each other and begin trading blows.
All Might immediately delivers a barrage of blows to a single spot on Izuku's arm, hoping that the suit won't be able to absorb such a highly concentrated amount of kinetic energy and break. Fortunately, he's correct, and the suit breaks enough to separate that arm of the suit from the rest of it. Unfortunately, Izuku wasn't bluffing about the nanomachines, and the arm immediately gets reattached, allowing Izuku to retaliate with a single punch that contains the kinetic energy of 10 of All Might's, breaking several of his ribs.
All Might coughs up blood from this, but presses on, delivering blow after blow at a rate that Izuku can't hope to keep up with due to his reaction speed being that of a regular human as opposed to All Might's own.
Izuku does deliver a few good blows here and there, dealing heavy internal and external damage to the Symbol Of Peace and keeping the fight seemingly close despite the massive speed difference between the two. But, eventually one of them is going to reach their limit and, unluckily for Izuku, it's not All Might who reaches his first.
"Master, The Annihilator's Kinetic Energy Storage has reached maximum capacity." Mavis warns. "If you take many more blows, the suit will overload and suffer from catastrophic failure."
Izuku curses under his breath, realizing that he has lost. "Well, guess I'll just have to find a way to increase the next model's maximum capacity." He mumbles. Unfortunately, All Might's keen hearing picks up what Izuku said, causing his grin to return.
"I think it's time we end this, don't you, Dr. Deku!?" All Might says, loud enough to ensure that both the remaining villains, and the fellow heroes that had just arrived, hear him.
Izuku sighs. "Yeah, The Annihilator has reached its limit." He admits, before holding his arms out wide in order to invite All Might to finish the fight. "Go ahead and put this suit to rest, All Might."
All Might laughs. "It was a close fight, Dr. Deku!" He compliments. "Had you landed even 5 more blows than you did, this fight would be ending in your favor rather than mine. Take pride in coming closer than almost anyone else to defeating me!" He says, before charging forward with his fist pulled back and landing a blow more powerful than any previous one and completely overloading Izuku's suit, causing it to self-destruct as he goes flying, before he disappears into a portal alongside the Nomu, returning both to Izuku's lab.
