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In the deepest confines of All for One’s underground compound stood a single room, one so off-limits that not even the villain’s most trusted subordinates were allowed inside. The only ones permitted to enter were the man himself and the current holder of One for All.
For you see, this room was designed with the sole purpose of being the place where All for One extracted the aforementioned Quirk from its user. Today, that user just so happened to be Izuku Midoriya, who had been strapped to a chair with chains so tight that not even All Might could break out of them.
A wicked smile split across All for One’s face as he watched the boy struggle in his confines. But as much as he wanted to savor the moment, time was of the essence, as All Might and several of the top pro heroes were currently fighting through a hoard of Nomu to try and save Izuku.
Of course, All for One would be more than happy to give him back, though depending on how well Izuku cooperated, it may not be in one piece. “Let’s cut right to the chase, shall we?”
“No! I won’t let you take One for All!” Izuku’s thrashing became even more violent, but that didn’t stop All for One from wrapping a hand around his face and beginning the Quirk stealing process.
“I don’t believe you have a choice in the matter. But don’t worry, this will all be over in a moment,” He laughed, sensing the familiar Quirk within Izuku, the one he tried and failed to steal so many times before. This time would be different, though. He could feel it. “Now where are you, brother?”
———————————————
From inside the Quirk factor of One for All, seven and a half figures stood valiantly at the edge of the cliffside, staring off beyond the horizon as they prepared to fend off the oncoming storm.
“Prepare yourselves,” Kudo ordered the others, “All for One hasn’t attempted to steal One for All in decades. Who knows how much stronger he’s gotten since then?”
“Oh, he’s gotten stronger alright,” Yoichi stated, able to read his brother’s aura better than anyone, “But that might end up working to our benefit.”
Kudo blinked at those words, turning to Yoichi to fix him with a perplexed look. “What do you mean?”
“He’s gotten a lot of Quirks since we last saw him, possibly a few too many, if you know what I mean.”
None of the Vestiges knew what he meant as they all confusedly narrowed their eyes at him. It wasn’t until a few short moments of silence that someone finally put the pieces together. “Oooooooh, I get it,” Banjo suddenly realized.
“Are you gonna tell us what you mean or keep being vague?” Bruce asked impatiently, “Because if Fifth is the only one of us that can figure it out, then you’re using some seriously backwards logic.”
“HEY!”
“No need to worry,” Yoichi replied in a tone that was all too calm given the situation, “If I know my brother, then we won’t have to lift a finger to solve this problem.”
———————————————
All for One’s laughter only grew louder and more pronounced as he began to siphon the energy from Izuku’s Quirk factor. Feeling the power he dreamed of possessing slowly fill his very being gave him a sense of satisfaction like no other. Mentally, he squealed with delight as he thought up all the ways he’d be able to crush those useless heroes outside his base with his newfound strength.
Then, the siphoning came to an abrupt halt, and the room became eerily silent as the two occupants stood there awkwardly facing each other, both unsure of what to say.
Now, being unable to steal One for All was nothing new for the Symbol of Evil, but it was normally due to the vestiges within his brother’s Quirk refusing to cooperate.
But that wasn’t the case this time. He couldn’t quite put his finger on it, but somehow, All for One felt as if he was the problem. But that couldn’t have been the case. When, in his entire life, had he ever been a problem?
“Um, are you okay?” Izuku asked, still unable to see from the villain’s hand obscuring his vision, “You kinda stopped stealing my Quirk all of a sudden. Did you like, run out of space or something?”
If All for One still had pupils, they would’ve shrunk down to the size of pinpricks. No… it couldn’t have been… There was no way All for One had a limit on how many Quirks it could hold. Even if it did, what were the odds of him reaching it right as he was about to take the one he’d sought out for the better part of a century?
But then again, if there was any Quirk that could push All for One to its theoretical limit, it would be the strongest one known to man. All for One trying to steal One for All would be like trying to fit a full encyclopedia collection into an already overstuffed library.
With that analogy in mind, All for One knew he had to burn some old books in order to fit the new ones on his shelves. Except there was one problem with that, he could only transfer Quirks, not destroy them. Since all his Nomu were busy fighting the heroes outside, the only one around to transfer Quirks to was…
“I have good news for you, Young Midoriya,” All for One grinned, hoping his use of All Might’s nickname would help mask his uncertainty regarding the whole situation. “I’m in a generous mood today. As such, I’ll leave you with a few parting gifts before I take One for All.”
“Uh, okay?” Izuku’s confusion was evident in his tone. From what he understood, gaining more Quirks could only be a net positive.
Knowing he didn’t have much time until the heroes came knocking on his doorstep, All for One quickly scanned his database of Quirks for unhelpful ones he could transfer to Izuku.
First up on the chopping block were the ones that allowed humans to withstand multiple Quirks without succumbing to rapid aging. The All for One Quirk already came packaged in with one of those, he just used the spares for Nomu creation, which he wouldn’t need after he obtained One for All.
With all that in mind, he bundled up all the Quirks and carelessly shoved them into his makeshift storage unit, who let out a sharp, painful scream that made All for One chuckle with delight.
Next up was all the duplicate Quirks. One for All would increase the strength of his preexisting Quirks tenfold, meaning he could gladly part with a few copies of Kinetic Booster, Brawl Booster, Speed-Up, Grip Strengthener, Muscle Mass, Regeneration, Endurance, and Super Leap.
That barely seemed to leave a dent in his Quirk reserves, though. Next, he’d have to dispose of Quirks that had been rendered functionally useless over the years. His eyes were all but gone, meaning he had no use for Quirks such as Laser Eyes, Piercing Glare, Medusa, Hypno Gaze, and Unblinking.
A similar sentiment could be said about the Symbol of Evil’s respiratory health, so he had no remorse in giving away Fire Breath, Ice Breath, Electric Breath, Poison Breath, Minty-Fresh Breath, and Underwater Breath, just to name a few.
Last was just the plain old weird Quirks he’d picked up over the years, such as Hue Shift, Slippery Sweat, Quick Dig, Fluffy Hair, Tip Calculator, Punching Bag, Cat Transformation, and a bunch of others he never even bothered remembering the names of.
———————————————
“Oh, here they come,” Yoichi causally stated as he peered up at the inky black void they called the sky.
“Here who come?” Questioned En, who would soon find his answer as a burly man dropped from the sky and fell right on top of him.
“W-Wha? Where am I?” The man nervously asked. He wasn’t alone in this situation, as his entrance was followed by dozens of other individuals dropping from the sky, each a vestige of one of All for One’s prior Quirks, suddenly finding themselves free from his influence.
“Hi, welcome to One for All. Enjoy your stay,” Yoichi causally greeted all of them.
“Wow, we’re really starting to build a community,” Nana gaped at the sudden influx of occupants, “We should seriously consider investing in some infrastructure besides a circle of thrones.”
“So much for minimalism,” Hikage sighed.
———————————————
All for One felt a sense of accomplishment as he deposited the last Quirk into Izuku’s body. Now that he freed up an adequate amount of space, there was nothing left to do but take what was rightfully his.
“I hope you enjoy all those extra Quirks in the five seconds you have left to live.” As his devilish smile returned, All for One tightened his grip around Izuku’s face, ready to steal his Quirk for real this time and put an end to this century-long brotherly feud.
Except, for some reason, he still didn’t have enough space to store it.
“Alright, what is going on here?” He frustratedly threw his hands in the air. “ I get rid of all these Quirks, and it’s somehow still not enough. If anything, it’s like One for All has gotten even bigger… than… before…” It was at that moment he realized the one major flaw in his plan. “The Quirks I gave you already fused with One for All, didn’t they?”
“Yup,” Izuku firmly nodded.
“Well, shit.” The villain quickly accepted his fate as Izuku used Slippery Sweat to help escape from his confines. In one swift motion, he activated all his strength and speed-enhancing Quirks and punched All for One in the face at full force, popping his head like a blood-filled balloon.
“And just to be safe…” He activated Laser Eyes and used them to disintegrate the villain’s headless body, leaving nothing behind except a small pile of ash.
Izuku didn’t seem at all deterred by the fact he just killed a man, instead humming a jaunty tune to himself as he skipped out of the underground compound without a care in the world. “Man, I can’t wait to try out all these new Quirks. I’m sure I can save a lot of lives with Fluffy Hair.”