The World of One Piece. The Slopes Above Shells Town.
"Kyle... is this really how you learn Observation Haki?"
Gon hissed through his teeth, his hand hovering gingerly over a fresh, throbbing lump on his forehead.
Kyle stood opposite him, rhythmically tapping a wooden staff against his open palm. "Exactly. Haki comes in three colors: Observation, Armament, and Conqueror's. The first two can be forged through training. But the third... Conqueror's Haki... that is chosen by fate. Only those with the disposition of a King can awaken it."
He raised the staff again, his expression unreadable.
Kyle's ability, the Book of Resonance, operated on a unique set of laws. The resonance only activated when a contract was signed and the partner was brought across the dimensional threshold. In the Hunter world, Kyle could not share in Gon's growth. But here, in a foreign dimension, the rules bent.
The contract granted the partner a body adapted to the new world's laws—allowing them to cultivate local powers like Haki—while Kyle acted as a mirror.
Every ounce of pain Gon felt, Kyle felt. Every flash of enlightenment Gon experienced was instantly downloaded into Kyle's soul.
This was why he swung the staff with such fanatical precision. He wasn't just training Gon; he was carving these reflexes into his own spirit. The pain was the price of power, and Kyle paid it gladly.
"Observation Haki functions similarly to En," Kyle explained, tightening his grip on the wood. "It heightens your senses to the absolute limit. It allows you to see the unseen, to sense intent before the muscle even twitches."
He pointed the staff at Gon. "We only have three days. You need to learn to dodge my basic attacks before we leave."
Gon rubbed the bump on his head one last time. He thought of the date on the calendar, of the clown magician waiting for him in the arena. The hesitation vanished from his eyes, replaced by a diamond-hard resolve.
"I'm ready."
Kyle tied a strip of cloth over Gon's eyes, plunging the boy into darkness.
The "special training" resumed.
Thwack.
The staff came down. The impact shuddered through Gon's shoulder, and simultaneously, a phantom ache bloomed in Kyle's own joint. He ignored it, swinging again.
Thwack.
Gon gritted his teeth, forcing himself to ignore the stinging pain and focus on the air.
Kyle's movements became fluid, almost manic. The shared agony was a feedback loop that sharpened his own focus. He needed this pressure. Only extreme stress could force the dormant senses to awaken.
Gon's talent was, frankly, terrifying.
For the first hour, he relied solely on his wild animal instincts, eating more hits than he dodged. But through the Resonance, Kyle felt the shift. It was like watching a spiderweb expand in the dark. Gon's senses were reaching out, feeling the displacement of air, tasting the faint killing intent encoded in each swing.
Swish.
Kyle swung low.
Without thinking, Gon's head snapped to the left. The wood sliced through the empty air, millimeters from his ear.
He had dodged.
Then came the second. Then the third.
It was no longer luck. Gon was beginning to see the invisible tracks of the attacks. Kyle smiled, feeling the shared revelation settle into his own mind, and immediately increased the speed.
Heavens Arena. June 26th, 1999.
Killua Zoldyck sat cross-legged on the floor, practicing his Ten, but his eyes kept darting toward the empty space in the center of the room.
"He said three days," Killua muttered, a thread of anxiety tightening in his chest. "If they're not back by noon..."
As if in answer, the air in the center of the room began to warp. Space folded in on itself, weaving a curtain of shimmering light.
Two figures tumbled out of the brilliance, hitting the carpet with a thud.
Kyle looked like a corpse; his face was drained of all color, his aura reserves completely hollowed out. Gon, on the other hand, looked electric. Despite the bruises and welts covering his arms, his eyes burned with a new, intense clarity.
"Gon!" Killua was on his feet in an instant. "You made it! What was it like? The other world?"
For Killua, the concept of an 'other world' was something from a fairy tale. Seeing it confirmed was enough to make the assassin's curiosity boil over.
"It was amazing!" Gon bounced to his feet, ignoring his injuries. "They have these things called Devil Fruits, and this power called Haki! It's different from Nen, but the feeling... it's similar!"
"Haki? Devil Fruits?" Killua's eyes sparkled. "Tell me everything."
He was so focused on Gon that he completely missed Kyle, who had silently crawled onto the sofa and collapsed, trying to meditate his aura back from zero.
Kyle closed his eyes, regulating his breathing. As the energy began to trickle back, he noticed something. The reservoir of his soul had expanded. Every time he forced the gate open, the strain tore his capacity wider. It was brutal, but it was working.
"So, this is Observation Haki?"
Killua stood behind Gon, his assassin instincts flaring. Without warning, he launched a chop toward Gon's neck.
Gon didn't turn around. He simply dipped his shoulder.
Killua's hand hit nothing but air.
"Yup!" Gon grinned, tapping his temple. "I can feel your intent. Even without eyes, I can feel where you're going to strike by the way the air moves."
"Hoh?" A competitive smirk tugged at Killua's lips. "Let's see you dodge this."
He moved. This time, he didn't hold back. His speed tripled, his hand blurring into a strike that utilized the rhythmic echo of the assassination arts.
Thud.
Gon sensed it, but his body couldn't keep up. The fist planted squarely into his cheek, sending him tumbling into the wall.
"Killua!" Gon sprang up, clutching his nose. "That was cheap!"
"You let your guard down!"
The two boys dissolved into a wrestling match, pillows flying across the room. Kyle, who was trying to cultivate in peace, took a stray pillow to the face. Then another.
His eyebrow twitched.
"Alright," Kyle sighed, grabbing a pillow. "War it is."
An hour later, the three of them lay sprawled on the floor, breathing heavy, the room a disaster zone of feathers and overturned furniture.
Killua rolled onto his side, his expression suddenly serious. He looked at Kyle.
"Kyle. I want to sign the contract too."
Kyle propped himself up on his elbows. He wasn't surprised. For a boy like Killua—raised in a cage of expectations and blood—the allure of the unknown was irresistible.
"Really?" Kyle asked, a genuine smile breaking across his face.
Killua blinked. He had expected hesitation, or perhaps a demand for payment. The Zoldyck family didn't do favors; everything was a transaction. But Kyle looked... happy.
The lack of calculation in Kyle's eyes disarmed him. It was a warmth Killua wasn't used to.
"Yeah," Killua nodded, his voice firm. "I'm in."
"That's perfect," Kyle beamed. "Welcome aboard. You're the third crewmate of my pirate crew."
"Pirate crew?" Killua raised an eyebrow. "You actually want to be a pirate?"
"In that world, 'Pirate' is just the title for those who live freely," Kyle explained, sitting up. "And we're going to need that freedom. The world is vast, Killua. The strongest monsters gather in a place called the New World."
"New World?"
"It's ruled by four emperors. The Yonko," Kyle said, his voice dropping an octave. "They are the pinnacle. All of them possess the disposition of a King. Three of them hold Devil Fruit powers capable of altering the environment itself."
Kyle paused, letting the weight of the next sentence settle.
"If we were to convert their Haki into Nen terms... their aura capacity would easily exceed one million units."
"One million?!"
Killua's pupils contracted.
He knew numbers. He knew power. A master Hunter might have fifty, maybe seventy thousand. One million wasn't a fighter; it was a natural disaster.
But the shock only lasted a second. The fear in Killua's eyes crystallized into a sharp, predatory calculation. He was already measuring the distance, analyzing the gap between himself and the summit.
"But we will surpass them," Kyle said. It wasn't a question.
Killua looked at Kyle's confident grin and found himself believing it. With the Resonance Contract, Kyle could compound their training. If they built a crew of monsters, Kyle would become the Leviathan that led them.
"I'm actually getting excited," Killua admitted, a dangerous light in his eyes. "Gon fights Hisoka in fourteen days. Shouldn't we go back? I want to learn that Haki stuff."
"I can't," Kyle shook his head, looking apologetic. "The gate has a cooldown. I have to wait three days before I can open it again."
"Hey, Kyle," Killua rubbed his chin, a thought striking him. "Have you thought about buying a ship? If we're going to be pirates, we need a ride."
"I've thought about it," Kyle laughed bitterly. "But I can't transport something that big through the gate. It's physically impossible."
Wait.
Kyle froze.
Big objects... transportation... shrinking...
A specific image flashed in his mind. A grotesque man in a suit, a member of the mafia's most feared enforcement squad.
The Shadow Beasts. Specifically, the one known as Owl.
Owl possessed a Conjuration ability called the Fun Fun Cloth. It could shrink anything it covered—people, cars, vaults—into a tiny, pocket-sized bundle.
If Kyle could get that ability... or get Owl...
He could buy a high-tech battleship in the human world and smuggle it into the Age of Discovery.
A slow, ambitious grin spread across Kyle's face. That wouldn't just be a ship. It would be an era-defining weapon.