The First Appearance of Nen

The waiting room on the 50th floor was lit by harsh white lights, the air thick with the smell of sweat and disinfectant. Fighters warmed up in their own ways—punching sandbags, stretching their legs, or leaning against the walls with their eyes closed.

Killua leaned against the metal wall, his hands in his pockets. The elevator doors opened, and Gon stepped out with a young boy in a white martial arts uniform. The boy had thick, neatly trimmed eyebrows, and his steps were light yet steady.

"Hello! My name is Zushi, and I'm a disciple of Shingen-Ryu martial arts! I saw your matches on the first floor just now. You were amazing!" Zushi clasped his hands together in a formal salute and bowed solemnly.

"Oh? Shingen-Ryu? Never heard of it." Killua raised an eyebrow, the corner of his mouth curling up. "Did you jump straight up from the first floor too?"

"Yep! The referee said I could go to the 60th floor, but I wanted to fight a few more matches on the 50th floor. My acting master said that would help build a solid foundation." Zushi nodded firmly.

The elevator attendant added an explanation of the 50th-floor rules—a three-minute point-based knockdown match. A Clean Hit was worth one point, a Critical Hit two points, and a Down one point. The first to accumulate ten points or knock out their opponent won.

Killua stepped out of the elevator, his gaze sweeping across the electronic display on the waiting room wall before stopping on a string of numbers. "Ring 57. My opponent is Zushi." He turned to Gon. "I'll wait for you on the 60th floor."

The announcement rang out: "Contestant 2055, Gon, please proceed to Ring 53 and prepare. Contestant 2044, Killua, and contestant 2066, Zushi, please proceed to Ring 57 and prepare."

Gon headed toward another ring.

Saitama sat in the last row of the contestants' section in the hall, stuffing a potato chip into his mouth. When he had bought corn at the entrance earlier, he had spotted chips on the convenience stand's snack shelf and grabbed a bag on the way. Barbecue flavor—the same kind sold during supermarket specials in Z City. They actually had it here too. The audience stands were full of the rustling of chip bags, and his chewing blended into the noise, slow and unhurried.

More than half the dipping sauce bottle in the plastic bag remained. He popped another chip into his mouth. Crunch.

In front of the television, Genos scooped the last spoonful of rice from the cooker into his bowl and sat back down at the coffee table. On-screen, Killua was rotating his wrists in front of Ring 57. He opened a bag of chips too—seaweed flavor, bought during the same supermarket trip as the barbecue-flavored bag on the coffee table. Last time, his teacher had said the barbecue flavor tasted better than the seaweed flavor, so this time Genos had bought three bags of each, intending to let his teacher choose when he returned.

He put a chip in his mouth. Crunch.

Ring 57 was covered in blue nonslip mats, with spectators packed all around it. The referee stood in the center in a black uniform, stopwatch in hand. By the contestants' area stood a bespectacled man—his shirt collar open, arms folded, a smile on his lips. Wing, Zushi's acting master and a Shingen-Ryu instructor.

The referee raised his right hand. "Contestants, ready—begin!"

Zushi immediately assumed the standard Shingen-Ryu fighting stance. His feet were shoulder-width apart, knees slightly bent, hands guarding his chest. His gaze was focused, and every muscle in his body was taut without a single opening.

Killua walked slowly toward Zushi, his hands still in his pockets. That stance is pretty solid—not something he picked up at the last minute. Shingen-Ryu, huh? Interesting.

"Ha!" Zushi took a deep breath and suddenly shouted. He burst forward, driving his right fist straight at Killua's face. The punch cut through the air with a sharp whistle, clean and precise.

Too slow. Killua shifted his body slightly, barely moving his feet as he effortlessly dodged the fist. He circled behind Zushi and tightened the edge of his right hand like a blade, striking precisely at the back of Zushi's neck.

A light smack rang out.

Zushi's eyes widened. His body instantly lost balance, and he pitched forward onto the mat. The referee quickly approached to inspect him. "Critical Hit! Contestant 2044, Killua, scores two points!"

The crowd began to murmur—the silver-haired brat really was strong; that Shingen-Ryu kid was no match for him; betting on Killua had been the right call. Killua stood beside Zushi, his hands still in his pockets. "Sorry, but before the 150th floor, this move is all I need."

Within ten seconds, Zushi pushed himself back up. He shook his head and resumed his Shingen-Ryu fighting stance, his eyes as focused as ever. "I haven't lost yet!"

Killua raised an eyebrow. He had not held back with that strike—by the standards of the opponents he had faced on the 50th floor, that hand chop should have kept someone down until the count ended. Yet Zushi had gotten up. There was no pain on his face, only concentration. I hit too lightly.

He sidestepped Zushi's straight punch again, circled behind him, tightened the edge of his hand, and chopped the same spot with greater force. Zushi fell face-first onto the mat once more.

The referee announced, "Critical Hit! Killua scores another two points!"

Zushi got back up again. This time, a trace of blood seeped from the corner of his mouth, but he merely wiped it away with his sleeve, resumed the Shingen-Ryu stance, and took a deep breath.

Killua frowned. It's not that I hit too lightly—I hit hard enough. This guy can just get back up.

Saitama sat in the last row of the stands and put a chip into his mouth. Crunch. The aura on the ring had begun to flow—not force, but the foundational form of Nen. Wing still stood at ringside with his arms folded, but a faint aura had begun to shimmer around Zushi's body. Finally. Saitama ate another chip. Crunch.

In front of the television, Genos put a seaweed-flavored chip into his mouth. Crunch. A faint halo appeared around Zushi's body on-screen—the first page of the Hunter wiki's section on Nen fundamentals had officially entered real combat at this moment. He swallowed the chip, reached for the remote, and turned up the volume. Then he reached for the notebook on the coffee table and opened it to the page marked with a tab—the definitions of the Four Major Principles had already been copied there in neat handwriting: Ten, Zetsu, Ren, Hatsu. His teacher was probably in the audience too, and the barbecue-flavored chips in his hand were likely already half gone.

Just as Killua was preparing to strike for the third time, Zushi's body suddenly changed. His fingers curled slightly, the muscles in his arms began to tremble, and a weak yet distinct aura spread from him, wrapping around his body like a pale halo. His expression shifted from calm to fierce, and his eyes gained a sharpness they had never possessed before.

!!! This feeling—it's just like Illumi! Killua's pupils abruptly contracted, and his body instantly went on guard. That invisible pressure radiated from Zushi like the tip of an extremely fine needle pressed against the back of his neck. He was no ordinary kid.

The audience erupted. The commentator cried out, "This child's presence has completely changed!"

"Take this!" Zushi charged at Killua again, his speed and strength greatly improved from before.

Killua instinctively retreated. His legs had made the decision on their own—it was not fear; before his mind could react, his body had already begun backing toward the edge of the ring. He had felt this pressure before. Whenever Illumi stood behind him, his body automatically retreated like this. He gritted his teeth and forced himself to stop, sidestepping Zushi's straight punch before swinging a backhand chop at the back of Zushi's neck again. But this time, Zushi only swayed after the strike landed—he did not fall, did not cough blood. He merely tilted his head slightly, then turned back, his gaze even sharper.

"Is that your only move?" Zushi stared at him.

"Zushi! Stop!" A shout suddenly came from the audience. Wing gripped the railing with both hands, his expression stern.

Zushi's body stiffened. The aura around him instantly vanished, clarity returning to his eyes as guilt appeared on his face. He immediately stopped moving, lowered his head, and bowed. "Acting Master! I'm sorry! I... I wanted to win too badly!" The oppressive sensation vanished without a trace. He had become that polite little boy again.

Wing offered no explanation. He climbed over the railing, walked to Zushi's side, and bent down to whisper in his ear—the voice was so quiet that only Zushi should have been able to hear it, but Killua's ears twitched. Zoldyck hearing training allowed him to catch those words: "...Before the 200th floor, you cannot use that power."

The referee declared Killua the winner, with a total score of 7 to 3. Killua did not raise his hand in acknowledgment. He merely watched Zushi return to Wing's side.

Saitama put the last chip into his mouth. Crunch. The chewing sounds in the back rows of the audience came to an abrupt stop. He looked down at the empty bag—barbecue flavor, the same kind from Z City. He crumpled the empty bag into a ball, stuffed it into the plastic bag, stood, and brushed chip crumbs from his pants. Wing's words had just pointed out the core threshold of Nen—Floor 200. Tomorrow, he would teach them "Ren." No rush. More than half the dipping sauce in the plastic bag remained.

In front of the television, Genos also put the last seaweed-flavored chip into his mouth. Crunch. He closed his notebook, picked up the remote, and paused the screen on the shot of Wing leading Zushi away through the contestants' passage. On the last page of his notebook, he wrote: Nen fundamentals training is about to begin. Teacher is eating chips. He crumpled the bag and tossed it into the trash can beside the coffee table, then added one more line: Barbecue flavor.