Chapter Text
The forum was called HeroNet Underground, and it was not, by any reasonable definition, easy to find.
It existed several layers below the usual social media ecosystems — not on the dark web, not illegal in any capacity, but deeply obscure in the way that only truly specialized communities could be. The registration required two recommendations from existing members, a written application explaining one's area of expertise, and a forty-eight-hour review period. There were no advertisements. There was no algorithm. The layout was plain, functional, and deeply reminiscent of forums from a decade prior, which its longtime members wore as a badge of pride.
HeroNet Underground was, in the estimation of its roughly eight hundred members, the single most intellectually rigorous hero analysis forum in existence.
Izuku Midoriya found it entirely by accident.
He'd been chasing a footnote — a specific citation in an academic paper about the theoretical upper limits of emitter-type quirks — and the citation led him to a paper, which led him to an obscure post on a now-defunct research board, which led him, through a chain of redirects that took forty-five minutes to untangle, to a cached thread on HeroNet Underground where someone with the username ChessNotCheckers had written a frankly staggering eight-thousand-word analysis of emitter quirk amplification, heat dissipation, and the biomechanical stress thresholds of the human nervous system.
Izuku read the whole thing in one sitting.
He read it again.
Then he spent three hours writing his own response in a document on his laptop, went to bed, woke up, reread both the original post and his response, edited it twice, and then spent another two hours trying to figure out how to actually register on the forum so he could post it.
He was twelve years old. He had been declared Quirkless at age four. He had eleven notebooks filled with hero analyses, quirk theories, and combat breakdowns. He had no friends.
He got in on his third application attempt, citing — with carefully anonymous precision — his work on quirk inheritance probability modeling and a three-thousand-word original piece on the gap between theoretical and practical quirk usage in professional hero work.
His username was GreenInk.
He posted his response to ChessNotCheckers' thread at 11:47 PM on a Tuesday, fully expecting nothing, and went to sleep.
───
By Thursday morning, ChessNotCheckers had replied.
GreenInk — I've been writing on this forum for three years and I can count on one hand the number of responses that have made me reconsider a foundational assumption. Your point about neural feedback latency in multi-activation emitters is one of them. I modeled the scenario you described. You're correct. I've updated the analysis in footnote 7. Where did you get your base data on the Kamui Woods incident? The public records are incomplete.
Izuku stared at the message for a long time.
Then he typed: I compiled it myself from video footage, witness accounts, and the partial hero agency report that was released under the Freedom of Information Act. I can share my raw data if you want. Also — the footnote 7 update is much more accurate now. Thank you for taking it seriously.
The reply came back in four minutes.
You compiled it yourself. Of course you did. Yes. Send me the data.
───
Nezu had not expected to be intrigued.
He was, by most measures, not easily surprised. He was the principal of U.A. High School, the highest-ranked educational institution for heroes in Japan. He held seventeen academic degrees. He had an IQ that standard tests were not sophisticated enough to measure. He had survived things that would have broken a lesser being — had survived them, catalogued them, and used them as fuel for something that was not quite bitterness but carried its edges.
He used HeroNet Underground because it was, quite simply, the only intellectual space where he could engage anonymously without immediately being identified. The forum's members knew him as ChessNotCheckers — a username chosen because, as he frequently told himself, he preferred to think several moves ahead of whatever game was currently being played.
He had not expected GreenInk.
The response to his emitter analysis was, frankly, remarkable. Not because it was perfect — it wasn't; there were two minor errors in the probability modeling and one overcorrection in the data set that suggested the author had access to incomplete information — but because the framework of the thinking was extraordinary. Whoever GreenInk was, they thought in systems. They thought about quirks not as isolated phenomena but as variables in a larger network of physical, biological, and social factors.
Nezu thought in systems too.
He sent three follow-up questions that same night, framed carefully so as to give nothing away about his own identity. He was curious whether the person would be frightened off by rigor. Many were.
GreenInk responded at 11:47 PM.
He was not frightened off. If anything, the questions seemed to sharpen him. His answers were careful, qualified where they needed to be, and bold where the data supported boldness. He cited his sources. He acknowledged gaps. He added a caveat to one of his own claims mid-response and explained why he was doing so.
By midnight, Nezu had ruled out every active researcher in the hero academic space he could think of. The writing style was too young — not unsophisticated, precisely the opposite, but it had a specific quality of enthusiasm that seasoned academics tended to sand away over time. GreenInk wrote about quirks the way someone wrote about a subject they loved, not one they studied.
Interesting, Nezu thought, tapping one claw against his desk in the dim light of his office. Very interesting.
He pulled up GreenInk's application. Anonymous. Careful. The pieces of original work cited were extraordinary but unattributable.
He couldn't figure it out.
He found that he didn't mind trying.