The sun had barely crested the jagged peaks of Mt. Colubo, but the morning air was already thick with the scent of pine and sweat.
"Hahaha! Is that all you've got, you oversized rug? Did you skip breakfast?"
A wild, unbridled laugh echoed through the forest clearing. In the center of the grove, a scene of pure primal power was unfolding.
Ten-year-old Portgas D. Ace, his lean, corded muscles glistening with sweat, was locked in a life-and-death struggle with a Great Bear—a mountain overlord standing over four meters tall. He carried no blade and used no flashy techniques. His hands were clamped onto the beast's massive shoulders, his feet digging deep furrows into the muddy earth.
Relying on sheer physical tenacity and a recovery rate that defied logic, Ace was meeting the forest king's raw strength head-on.
"ROAR—!" The giant bear let out a frustrated rumble, its strength finally flagging against the boy's immovable stance.
Bang!
With a sudden shift in weight, Ace executed a perfect shoulder throw. The massive creature hit the mud with a bone-shaking thud. Dazed and defeated, the bear didn't retaliate; instead, it rolled over, rubbing its head against Ace's leg like a scolded puppy.
"Good effort. I'll toss you half a roasted crocodile later," Ace said, patting the bear's head before casually sitting on its soft, rising belly.
"Ace! Stop bullying the local wildlife!"
The underbrush snapped as Sabo and Luffy emerged, gasping for air. Both boys carried massive logs across their shoulders. They looked like they had crawled out of a swamp, their bodies trembling from exhaustion as they collapsed onto the grass.
"Bullying? This is 'sparring,' Sabo. Look at the progress," Ace gestured to the edge of the clearing. Several tigers, crocodiles, and mountain primates were lounging there, looking thoroughly beaten but oddly docile.
"They look like they were punched into submission, not sparred with," Sabo wheezed, rubbing his throbbing shoulders. "But seriously... this 'Marine Headquarters Elite Drill' you pried out of the old man is going to kill us."
Ace didn't disagree. He knew that the most scientific, limit-breaking physical training in the world was locked within the Marine system. Every time Garp returned to the East Blue, Ace made it his mission to manipulate or pester the Vice Admiral into revealing the secrets of the elite—weighted cross-country runs, waterfall endurance, and high-pressure deep-sea diving.
What was meant for grown men in the Grand Line had become the daily ritual for three children on a remote island.
"If we don't polish every inch of muscle to the limit now, how do you expect to walk tall on the open sea later?" Ace stood up, his joints popping like small explosions. "Luffy! Enough napping! Go practice your impact resistance with that Great Ape!"
"Aaaaah! Not the ape! Help me, Ace!" Luffy screamed as he was tossed into the air by a flexing primate, bouncing off the ground with his rubbery body.
Sabo watched Luffy's "training" with a grimace before turning to Ace. "And you? You finished your basic sets in the middle of the night, didn't you?"
"Me?" A sharp, hungry grin tugged at Ace's lips. He looked toward a row of thick wooden stakes driven deep into the ground. "Today, I'm trying to dismantle the old man's footwork."
Before Sabo could ask what he meant, Ace's silhouette blurred.
Snap!
A faint sonic pop cracked in the air. Ace vanished from his spot like a ghost and reappeared instantly ten meters away, standing directly in front of the center stake.
Sabo's eyes nearly bulged out of his head. "That... that's the teleportation move the old man uses before he cracks our skulls!"
"He calls it 'Soru,'" Ace said, glancing back with a grin. "It's about kicking the ground dozens of times in a single heartbeat to create explosive speed. It's part of something called the Rokushiki."
Ace had been "listening" to the rhythm of the world since he was small—a latent, raw Observation Haki that allowed him to feel the vibrations of Garp's movements even while being beaten. He wasn't just taking hits; he was stealing techniques.
He wanted it all—the explosive Soru, the aerial freedom of Geppo, and the fluid evasion of Kami-e.
Bang! Bang! Bang!
Ace continued to vanish and reappear. His movements were still raw, and his speed was a fraction of a Marine Admiral's, but his terrifying physical talent was already forcing the technique into reality.
"He really is a monster," Sabo muttered, watching the afterimages flicker across the field. He had always considered himself talented, but Ace was playing a different game entirely.
"Don't just stand there, Sabo! Come and see if you can hit me!" Ace flashed in front of him, swinging a heavy hook.
"Hey! Watch it, you bastard!" Sabo scrambled, raising his metal pipe to parry the blow.
"Hahaha! If you can't even block a warm-up punch, how can you be the First Mate of the Eclipse Pirates?"
As the sun dipped below the horizon, the roars of beasts and the laughter of boys blended into the soundtrack of Mt. Colubo.
Later that night, the three brothers sat around a crackling campfire, tearing into the "tribute" crocodile meat.
"Ace," Sabo said, his face illuminated by the dancing orange light. "I heard the old man bragging while he was drunk. He said the real monsters of the sea use a power called 'Haki.' When are you going to make him teach us that?"
Even Luffy stopped chewing, his large eyes turning toward his older brother.
Ace swallowed a mouthful of meat and wiped the grease from his chin, his eyes reflecting the deep, dark embers of the fire. "It's too early for that."
He leaned forward, his voice dropping into a tone of sober intensity. "Haki is the manifestation of will and vitality. If you don't have a monstrous physical container to hold it, trying to force Armament Haki just burns out your potential. It's like putting a massive engine into a wooden boat—it'll just shake itself apart."
Ace raised a clenched, oil-stained fist. "Right now, we treat our bodies like sponges. We soak up every bit of nutrition, we polish every muscle, and we push our limits until this mountain has nothing left to teach us."
"When we hit fifteen, and our frames are fully grown..." Ace's grin returned, wider and more dangerous than before. "I'm going to pry the old man's mouth open and squeeze every secret of Haki and martial arts out of him until there's nothing left."
He stood up, facing the cool night wind blowing in from the coast.
"And then, when we're seventeen... we set sail and turn this boring world upside down!"