"Huh..."
As he slowly drew back his fist, the overwhelming Haki that had infused Zephyr's body gradually subsided. The muscles that had been shifting and surging with the Haki flow throughout his body slowly returned to normal.
Fine beads of sweat appeared on Zephyr's forehead.
"...I'm getting old." Feeling the fatigue emanating from his body, the old man sighed inwardly.
The punch that had severed the deep-sea current was unleashed with absolutely no reservations; it was his true, all-out power.
Using the Black Body Style, he controlled every part of his body and stimulated its maximum potential. His already pinnacle-level Haki erupted with unimaginable might.
Back in his prime, he could maintain this state for a very long time. But in recent years, such an attack has placed an enormous burden on his body.
In fact, it had been the same four years ago when he encountered the pirate who attacked him at sea. Back then, Zephyr nearly crushed his opponent while fighting at full power.
Yet, that pirate relied on monstrous vitality to survive and endured until Zephyr's body could no longer bear the strain, ultimately leading to the tragedy four years ago.
According to the SSG scientists who examined Zephyr and created his new arm, within a few years, his body might no longer be able to use the esoteric techniques of the Black Body Style, and sustained high-intensity combat would become extremely difficult.
This was the power of time.
Even an Admiral who once dominated the seas would grow old.
Fortunately...
"There are successors." Zephyr took a deep breath, turned around, and saw Roy, his eyes blazing with fervor.
He grinned.
"Well, kid? What do you think?"
"Awesome."
What else could Roy say?
"That thing just now was..."
"This is the true Black Body Style," Zephyr said proudly. "First, temper your body until you can control every part of it. Then, use that control to guide and master Haki."
"When you use Haki, you control every part of your body, squeezing out its potential and coordinating it with your Haki."
This was the most distinctive aspect of his physical combat style. Many powerful fighters could infuse Haoshoku Haki into Busoshoku Haki.
Among them, there were plenty whose raw Haki strength surpassed Zephyr's.
However, just like the punch Zephyr had demonstrated earlier, when he threw that punch, it wasn't only Haki that was flowing.
Every part of his body was squeezing out its potential.
That's why his technique is called "Black Body" and not "Black Arm"!
And so, Roy had no more complaints.
What was there left to say?
Train!
Afterward, under Zephyr's guidance... Roy didn't hesitate. He picked one of the countless surging "Black Snakes" and leapt straight into it.
Then...
"!!!"
Pain struck once again.
But this time it was different from the deep-sea water pressure before.
While the deep-sea pressure had been like a massive mountain pressing down on Roy's body... this time, the enormous deep-sea current was like that mountain growing fists and smashing him with a heavy punch!
No... one hundred punches!
"Hōng Lóng!"
Even after becoming sturdier, nearly steel-like, after obtaining the Dice-Dice Fruit, Roy felt that his tendons and bones were wailing in agony.
"Hold on. Feel the changes in your body. Feel the power in every inch of it. You're terrible at controlling your body. Most of your strength is being wasted."
Zephyr's voice reached his ears at that moment.
Hearing this, Roy clenched his teeth hard.
But after only a short while, exhaustion overwhelmed him. His body went slack, and like a withered leaf, he was caught in the violent sea current and swept toward the depths.
At that very moment, Zephyr's figure suddenly flashed. He appeared in the current, grabbed Roy with his left hand, and pulled him out.
Without waiting for Roy to speak, Zephyr said, "Some muscle fibers are torn. The bones should be fine. Given your recovery ability, how about starting the next round of training in ten minutes?"
Roy bared his teeth and laughed. "Seven minutes is enough."
"Good kid." Zephyr grinned, the satisfaction on his face growing clearer. "Then seven minutes. This old man will prepare more coating bubbles for you."
With that, he turned and left.
Meanwhile, Roy calmly remained in the deep sea, quietly feeling his body recover.
His eyes were filled with resolve.
Normally, he was a lazy guy. But when effort was required, he never backed down.
Seven minutes later, Zephyr returned.
Without hesitation, Roy plunged headfirst back into the raging waves.
Once, twice, three times...
In the silent depths of the sea, Roy was tossed around by the "Black Snakes," only to be pulled back by Zephyr each time.
"The muscle efficiency in your left calf is much worse than in your right leg. Do you know why your shoulder blade broke this time? It's because just now you..."
"The force from your abdominal muscles needs to shift further back. Feel it. Next time, control your output to seven parts."
"That's it, exactly... now you have to control your heart rate to increase blood flow."
"Keep going! At your age, how do you even have the nerve to sleep?"
It was here that Zephyr truly demonstrated why he was hailed as a legendary Marine instructor. Whenever Roy failed, Zephyr could pinpoint his problem with uncanny accuracy.
Through these repeated failures, Roy began to feel changes in his body.
The steel-like skin granted by the Dice-Dice Fruit seemed to grow denser and tighter with constant use.
He was also gaining increasingly refined control over the power granted by the Giant Rhino Fruit and the Muscle-Muscle Fruit. He could clearly sense which muscle had torn, healed, and grown stronger.
"I'm growing stronger... without adding any Enhancement Ability, but I really am growing stronger."
Roy could perceive this with absolute clarity.
This realization almost enabled him to ignore his exhaustion and continue training like a madman.
Until one particular training session...
"Crack!"
Roy stood in the middle of a raging current, desperately trying to control his body as it confronted the massive flow head-on.
His heart pumped blood at high speed, and his muscles were fully engorged. Gritting his teeth, he stretched out both hands to maintain his balance.
Then...
"Buzz!"
At one point, he felt something unprecedented appear in his body.
Roy found it hard to describe that sensation.
It wasn't an Enhancement Ability. Rather, it felt as though some kind of power was surging from deep within his bones and muscles.
It seemed to exist in every part of his body, like magma hidden beneath a submarine volcano.
However, the sensation vanished in an instant, so quickly that Roy thought it might have been a misconception. So, when the sea current swept him away once more, and Zephyr fished him out again,
Roy immediately asked Zephyr about what he had just felt.
Then...
"You felt it?" Zephyr glanced at Roy, looking slightly surprised.
"Of course it wasn't a misconception. What you felt was your own Haki."
"As expected..." Hearing this, Roy inwardly muttered, "Just as I thought. So that was Haki?"
He had already guessed that the power existing within him that wasn't an enhancement ability could only be Haki.
But the problem was...
"How do I use it?" Roy looked at Zephyr with anticipation.
Zephyr chuckled and looked back at him while speaking. "What are you thinking, kid? Do you think it's that easy?"
He didn't hold anything back, explaining his understanding of Haki directly to Roy.
"Haki exists within everyone. It's just stronger in some and weaker in others."
He raised a finger.
"Except for Haoshoku Haki, which is somewhat special by nature..."
"The other two types of Haki can be obtained through practice. The stronger your physique, the greater your potential for Busoshoku Haki. The sharper your senses, the greater your innate potential for Kenbunshoku Haki."
As he spoke, he pointed at Roy.
"Your body is strong, like a monster's. Naturally, your Busoshoku Haki potential is absurdly high. It's perfectly normal that you'd sense it so quickly."
"But sensing Haki is only the first step. Tempering and guiding it out is the real key to Haki training."
Hearing this, Roy was inevitably disappointed.
"Then how long will it take me to guide Haki out? How long until I reach your level?"
He really needed Haki; when facing Logia-type users, Busoshoku Haki was indispensable.
Zephyr didn't hesitate at all.
"To initially guide out Haki, about half a year."
"To use the Haki in your body proficiently, even those with high talent usually need one to two years."
"As for reaching my level..." Zephyr paused. "With your physique and talent, about ten years should be enough to fully draw out all the Haki within you. By then, you should have completely mastered the essence of the Black Body Style as well."
At this point, Zephyr's eyes were filled with anticipation.
In his view, Roy wasn't even thirty yet.
Ten years later, he'd still be under forty, right at his peak.
Zephyr was absolutely certain that version of Roy would definitely be stronger than him!
'That Garp bastard keeps bragging in front of me about Kuzan learning his Iron Fist. When the time comes, I'll show him just how strong Zephyr's successor really is!'
But clearly, Roy was stunned by what he heard.
"Half a year just to master Haki?"
"One to two years to use it proficiently? Ten years to reach the peak?"
He could understand Zephyr's words; his physique was too strong, so his Haki potential was huge, too. Naturally, developing it would take a lot of time.
Moreover, even Luffy, whose combat talent was maxed out and who carried the protagonist's halo, still needed two years of training under someone like "Dark King" Rayleigh to master Haki.
By comparison, Zephyr's evaluation of Roy's potential was extremely generous. But for Roy, this timeline still felt far too long.
"Isn't there something like a Haki Fruit?" He muttered to himself.
Obviously, Zephyr had no idea what Roy was thinking.
After finishing his mental image of showing off his disciple ruthlessly in front of his old friend in the future, Zephyr turned back to Roy.
"Rested enough? If so, then keep going. Do ten more rounds today, and then we'll head back!"
"Ten... ten times!?"
(End of Chapter)
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