Inside the capsule—
Kai endured the ultra-intense current surging from every direction.
Zzz—zzz—zzz!
Blinding arcs of electricity flashed nonstop, and the faint smell of scorched flesh began to seep from his skin.
Every strand of current was like a sharp steel needle, trying to punch straight through his body.
Every breath—
Pulled threads of electricity into his lungs.
The current tempered his organs, meridians, bones, and blood.
Finally—
Under the brutal refinement of the Level Ten current, Kai snapped his eyes open. A dazzling gleam burst from his pupils, and his exhale even carried flickers of lightning.
"Level Ten stimulation…"
"Is that all?"
He chuckled.
A full year of bitter training had pushed his body to an utterly absurd realm.
Even Level Ten current could no longer seriously damage him.
In fact—
As his strength increased, the training effect of the electrotherapy method had begun to shrink to almost nothing.
Simply put:
For Kai right now, the electrotherapy capsule was no longer that useful.
A full year invested into this method had given him surge after surge—
But after a year, he had become too strong.
He was completely different from who he was a year ago.
A total rebirth.
Half a beat later, the current inside the capsule gradually shut down.
Kai reached out and pushed open the liquid-crystal glass door.
Creak.
With a soft sound, the door opened, and he stepped out.
The sealed chamber was lit with dazzling, multicolored lights—bright and clear.
Under the lights, Kai's powerful physique was fully revealed.
His bare upper body was packed with muscle definition.
Blue veins—thick like centipedes—crawled across every tightened muscle group. Each muscle looked honed into a perfect shape, like a volcano that had been suppressed for too long.
Every single one contained terrifying explosive power.
And once that power erupted—
It would be earth-shattering.
Bulging muscle, and on top of that—
The grotesque Ghost Back.
Like a devil's pattern carved into his flesh.
It had become clearer. More obvious.
And it radiated a heavier, more oppressive aura than ever—so dense it felt like it could almost become tangible.
If an ordinary person dared approach him right now, they'd likely collapse from the pressure alone.
Kai exhaled heavily and turned to look at the capsule, emotion flickering in his eyes.
"One year…"
"Without realizing it, a whole year is gone."
For this entire year, Kai had maintained high-intensity electrotherapy training almost every single day, forcing his strength to skyrocket.
In that year, aside from this research institute, he had almost never left.
So to the countless Marines in Marineford…
Kai was as if he'd vanished into thin air.
No traces. No news.
Even his fellow trainees from the same generation were curious where he had gone.
Other than Marine high command, almost nobody knew his whereabouts.
No one could've imagined—
Kai had stayed inside the research institute for an entire year.
One year without stepping outside.
Training at extreme intensity every day.
If you counted it all up…
Kai's daily electrotherapy time was no less than six hours.
Double Zephyr's original warning of three hours.
And he kept it up for an entire year.
Yet even so—
Not only did his body show no hidden injuries or lingering risks, he looked more vigorous than ever. Clear-eyed. Energetic. Powerful.
"I wonder how much happened outside…"
"I've been here a year. The sea must've gotten a lot more interesting."
"It's time to leave."
Kai narrowed his eyes, making his decision.
Because the capsule's stimulation no longer helped him much, it meant one thing:
He had hit a new bottleneck.
A higher, harsher threshold.
Not something he could break in a short time.
He needed time to settle and refine.
So he wasn't planning to keep staying here.
"I wonder how Smoker and the others have progressed over this year…"
Kai smirked with interest.
He'd disappeared from the training camp without a word and stayed missing for a full year.
Smoker and the others had definitely used him as their target.
The only question was—
How strong had they become?
"In the blink of an eye, I'm five years old."
"Time really flies."
"I've been away from the East Blue for over a year now… I kind of miss it."
"I wonder how Ace is doing taking care of my idiot little brother Luffy."
"And the villagers in Foosha Village…"
Kai felt a wave of nostalgia.
A year locked away in closed-door training made him curious about the outside world again.
He was a social creature, after all—not a lone beast.
Thankfully, there were always researchers here to talk to.
Otherwise, he might've truly become detached from normal life.
"I should find a chance to ask them what's been happening out there."
Kai rolled his shoulders, then quietly called up his status.
"System. Open my status panel."
Before it even appeared, his heart was already full of anticipation.
A full year of rebirth—
His panel was bound to be completely different.
A moment later, the virtual display appeared in his vision.
[Host: Kai]
[Strength: 148.1 (+102.9)]
[Speed: 140.6 (+109.4)]
[Stamina: 140.6 (+101.1)]
[Mental Power: 63.0 (+43.8)]
[Ghost Back Completion: 19.19%]
[Overall Training Effect Boost: 100x]
This was the result of one full year.
One year was long.
For ordinary people, a year of hard work might not even show much change.
But for Kai—
One year was enough to flip his entire existence upside down.
Compared to a year ago, he wasn't just "stronger."
He was stronger by hundreds of times.
Maybe thousands.
And the panel made that painfully obvious.
Strength, speed, stamina—each of them had increased by over a hundred points.
Everyone knew the truth:
The stronger you became, the harder it was to improve.
Yet Kai used only one year to multiply his strength to a ridiculous degree.
He had become so strong that even he didn't know his own limit anymore.
And it wasn't just his physical stats.
His Mental Power had surged by over forty points—meaning his Conqueror's Haki intensity had climbed to another level.
Kai could say with full confidence:
Even if it was someone like Sengoku—
If they compared Conqueror's Haki intensity, Sengoku would likely be far behind him now.
And finally—
Ghost Back Completion.
He was less than 1% away from 20%.
Just a little more—
And he'd cross 20% and unlock a brand-new ability.
Kai's eyes lit up at the thought.
Two hundred times training boost?
Five hundred?
A thousand?
Just imagining it made him feel almost delirious with excitement.
Of course—
Beyond the panel, his techniques had also improved massively over the year: Rokushiki, advanced applications, Armament and Observation Haki—everything.
His growth was comprehensive.
"Right now…"
"Even barehanded—without using any combat techniques…"
"I could casually smash a pirate worth over a hundred million Berries."
"Even without Rokushiki, without Haki… just my physical stats alone would be enough."
Kai clenched his fists.
He could feel it—
An overwhelming force sleeping inside his body.
World-ending.
That wasn't an illusion.
If he threw a casual punch here…
He might collapse the entire research institute.
"And if I'm not mistaken…"
"My combat power has definitely reached Marine Headquarters Vice Admiral level."
"Maybe I'm still below monsters like Akainu, Aokiji, and Kizaru… or my old man Garp, or Vice Admiral Tsuru."
"But compared to ordinary Vice Admirals, I won't lose."
"I might even be stronger."
"If you put me among Vice Admirals, I'd still be near the very top."
Kai withdrew his gaze from the panel and laughed softly.
One year had passed.
He was five years old now.
A few months ago, he'd already celebrated his birthday here in the institute.
And he didn't feel sad about it at all.
Because his power had reached a new level.
A five-year-old with Vice Admiral-level combat power.
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