Etsuha repeated the process three times, carefully copying multiple Nomu gene sequences before finally leaving.
"Other than the two intact quirks, the failed transplantations are the main reason humans turn into Nomu. And there are certain genes in their bodies that are completely identical… If I'm not mistaken, those must be artificial sequences introduced by the doctor."
As he walked, Etsuha mentally reviewed everything he had observed, jotting down key details in his notebook.
For someone operating on the side of justice, the biggest limitation was obvious—there were lines that couldn't be crossed. His gene manipulation ability could heal injuries, but using it to replicate or transplant quirks—especially something like Nomu abilities—was dangerous. If something went wrong, he could turn a normal person into a monster.
The consequences would be catastrophic.
Villains, on the other hand, had no such restrictions. The doctor behind the Nomu had clearly conducted countless human experiments, accumulating data and experience far beyond anything Etsuha currently possessed.
Still, Etsuha had no intention of recklessly transplanting Nomu quirks into humans. His real goal was to study the differences between quirk gene structures—so that one day, he could perform safe and controlled transfers.
"I'll need some test subjects."
As he left the prison, his thoughts remained fixed on quirk genetics. Since human experimentation was out of the question, small animals would have to suffice.
Fortunately, a pet shop wasn't far away. Etsuha picked up two white lab mice and began experimenting almost immediately as he made his way back.
"Since Principal Nezu evolved due to an awakened animal quirk… this should theoretically be possible."
Holding one of the mice, Etsuha focused and carefully introduced a regeneration-type quirk gene into its body.
"Squeak!"
The mouse instantly became agitated. Its entire body convulsed violently, its pores bulging grotesquely—until, within moments, it fell lifeless.
Etsuha examined the body again, analyzing the genetic structure.
"The regeneration quirk is too complex… Once introduced, it destabilized the mouse's entire system and caused a complete collapse."
He frowned slightly.
"Is it because the mouse's body is too weak… or because the quirk itself is too powerful?"
For the second mouse, Etsuha drastically reduced the gene load of the regeneration quirk—cutting it down dozens of times. The result was far weaker, essentially rendering the ability useless.
This time, after injection, the mouse became aggressive and restless—but remained alive.
"No structural collapse… but increased aggression."
A glint of understanding flashed in Etsuha's eyes.
"So the issue really is the quirk itself."
With that conclusion, he decided to pause further experimentation for now.
Soon after, Etsuha arrived at U.A. and found Aizawa Shouta already waiting.
"You're early, Shina," Aizawa said, sounding slightly surprised. "I figured you'd show up tomorrow, knowing you."
"Just happened to be nearby," Etsuha replied casually. Then he got straight to the point. "So, about this 'final boss' role—what's the actual plan?"
Aizawa yawned before answering.
"U.A.'s entrance exam usually revolves around defeating robots. The more you destroy, the higher your score. That part hasn't changed. But this year is… different. As I told you before, the school wants something more impactful."
"…Right. 'Impactful,'" Etsuha muttered dryly.
Ignoring the comment, Aizawa continued, "Once a candidate reaches a certain score threshold, they'll gain access to your area. That's when you step in. All you need to do is demonstrate your strength."
"And if they beat me?"
"They'll receive a significant reward," Aizawa said. "So don't worry—they'll definitely challenge you."
Etsuha raised an eyebrow. "That's it?"
"This is just the overview," Aizawa replied, clearly annoyed. "The full plan is much more detailed."
"Fine. So what do I do before someone challenges me? Just sit there and wait?"
"Not necessarily. You only need to appear toward the end. Before that, you're free to do as you like."
"In that case," Etsuha said casually, "I'll just follow the examinees around. I've got nothing better to do anyway."
"That's fine," Aizawa nodded. "Just don't interfere with their scores. Otherwise, it'll disrupt the entire system."
"No problem."
And just like that, the plan for U.A.'s "final boss" was settled.
Of course, as Aizawa had mentioned, the actual structure of the exam was far more complex—complete with scoring systems, thresholds, and reward conditions. These were later explained to Etsuha in detail by the principal.
After that, things became relatively uneventful.
U.A. remained closed for the time being, and there weren't many students on campus—but the teachers were already busy preparing.
Among them, All Might had taken it upon himself to give Midoriya Izuku some last-minute intensive training. It was clear he was deeply concerned about the boy's upcoming performance.
Time passed quickly.
Before long—
The next day arrived.