Once all of the heroes had invaded City Z and Sekingar had sent all of the S-class heroes into the monster hideout, Puri-Puri Prisoner continued his own search, boring through the underground walls of the Monster Association base.
He ended up in a small chamber filled with torture equipment, and noticed Garou chained to the wall, seemingly unconscious. Not recognizing him as the infamous hero hunter, Puri-Puri Prisoner thought he was simply another human hostage and moved to release him, introducing himself as an S-class hero. However, just as Puri-Puri recognized Garou's face from the wanted poster, Garou awoke and broke the chain before swiftly pummelling the hero with a multitude of strikes.
Above them, Saitama went on with his own chill little excursion inside the association.
Back below, Puri-Puri Prisoner was being absolutely pummelled by Garou, getting blasted through multiple walls until he lay there battered and bruised, completely unable to move. However, as he lay there, a big shiny black leg muscle appeared directly beside him, revealing Superalloy Darkshine, who had managed to stumble upon him at exactly the right time.
Weakly, Puri-Puri filled him in on the situation, as opposite the two huge men a dark, bulked-up figure of Garou stepped out.
Elsewhere in the base, the battle between Tatsumaki and Psykos had really only just begun, and so had this one. True hell had broken loose before Darkshine, as Garou had pretty much lost his mind, not thinking, just attacking over and over again.
Suddenly, as Superalloy called him a monster, Garou snapped back to reality, as technically he had actually been asleep, attacking on pure instinct from the moment Puri-Puri Prisoner had disturbed him. Darkshine launched at him and attacked the now-awake hero hunter. But after being pummelled, Garou simply stood there, challenging the reasoning for Darkshine even being a hero in the first place, as well as the entire hero society's way of thinking.
Popping out those immaculate muscles, Darkshine unleashed a devastating tackle that pierced through Garou's guard with ease and sent him flying back through multiple layers of the Monster Association. Garou's ribs were completely shattered by the blow, but he soon recovered and began using his techniques to fight against the hero. Firstly, he used Water Stream Rock Smashing Fist to pummel the huge man, followed by Whirlwind Iron Cutting Fist to land a complete onslaught that made the indestructible hero consider the possibility of defeat, and his entire reasoning for actually becoming a hero in the first place.
Reconvincing himself that he, Darkshine, had the strength to take down this base of a monster, he then used his full power to punch Garou and used his prolific super alloy bazooka. But to his complete and utter shock, Garou met his fist with a blow of his own. And in that exact moment, Garou also finally proceeded to an even higher level of strength, with his limiter beginning to break.
Deep inside the association, Garou continued his beatdown on Superalloy Darkshine. He slipped past a punch from Darkshine and delivered a strike that forced the hero to drop down, coughing.
Standing above the S-class hero, Garou taunted Darkshine, who looked at him in complete fear. It was explained that when he was a child, Darkshine had been a frail weakling, unable to participate in sports and other physical activities. His frailty had left him unable to build any form of self-confidence. On his fifteenth birthday, though, his parents gave him a set of three-kilogram dumbbells.
From that day onwards, he lifted every single day, gradually increasing the weight until the amount he could lift was immeasurable. His progress through this built up his confidence to the point that he eventually joined the Hero Association and continued his search for an opponent who could push him to his limits.
As Garou continued his assault, Darkshine realized that he had never been looking for a real fighter. Rather, he had sought a fight that could give him a satisfying victory. The thought of injury instantly flashed through Darkshine's head. The most powerful fear he had long forgotten began to grow and overwhelm him completely, crowding his thoughts.
Darting forth, Garou kicked him in the stomach and pinned him to the ground with a follow-up kick to the chin. He moved to strike at Darkshine's ears, but pulled back when the hero yelped in fear. Standing above the cowering hero now, Garou judged his assault to be akin to bullying, a pathetic evil compared to what he aimed to become in the future.
Suddenly, Garou's joints started cracking, and the dark marks on his body crawled towards his face.
Then, even more randomly, psychic barriers were created by Tatsumaki that surrounded Darkshine and pulled him up as the ceiling of the room collapsed in, leaving Garou on the ground amidst the falling rubble. Tatsumaki then dragged the entire Monster Association headquarters to the surface.
Tatsumaki and her interruption had robbed Garou of what was almost a sure kill right there. On top of that, it also left an unimaginable weight of debris crushing him down.
Even still, Garou, who was deep underground, buried under all that falling debris, began rising up. Slowly rising, he pondered the idea of why the more he was beaten, the more he felt like he was getting stronger.
He came to the conclusion that through these surges of strength he was one step closer to becoming the monster that he wished to become. Internally, he fully envisioned himself as despair incarnate, desiring to make the world become the way he wanted it to be. And with that, his body once more began transforming into a more monstrous state.