In a cold, dark cave,
an extremely old Uchiha Madara sat motionless on a stone chair.
Gripped tightly in his hands was a sickle-shaped weapon, reminiscent of his youth. Behind him stood the emaciated shell of the sacred tree—the Gedo Statue.
At this point, Madara's body had already aged beyond recognition. He remained alive only by leeching vitality from the Gedo Statue.
"White Zetsu, you returned early," Madara's hoarse voice echoed through the cavern. "Did you find anything?"
From the damp soil, a plant-like humanoid emerged, half-white and half-black, eerily grinning.
"Ah~ Lord Madara," White Zetsu said in his shrill tone. "I found an interesting Uchiha boy. He awakened the two-tomoe Sharingan at just seven years old."
Madara's half-lidded eyes slowly opened. "Oh? What's his personality like?"
White Zetsu shrugged playfully. "Unlike the usual arrogant Uchiha, this boy is cheerful and kind. He's even been seen helping old ladies cross the street."
He giggled. "And the best part—his dream is to become Hokage."
"Heh~"
Madara chuckled, his laugh laced with cruel amusement.
What a naïve little fool.
Did he really think Konoha would ever allow an Uchiha to become Hokage?
Madara had long since severed all ties with the village that betrayed him.
Still…
"A child like that may be worth cultivating," he murmured. "After all… I don't have much time left."
His expression turned serious. "White Zetsu, keep an eye on that boy. And everyone around him. We may need them in the future."
"Yes, Madara-sama!"
---
"Aahhh! Nooo! I wanna lie down!"
In a clearing deep within the Konoha Forest, Kakashi was sprawled out on the grass, looking thoroughly defeated.
Surrounding him were stacks upon stacks of scrolls—each one packed with intricate sealing formulas.
Two and a half years had passed since he'd become Tsunade's apprentice.
During this time, Kakashi had demonstrated an almost demonic learning speed.
Theoretical medical ninjutsu? He mastered it faster than most could blink. That was impressive, but not too surprising.
But once it came to practical techniques—like the Healing Jutsu, Chakra Scalpel, Super Strength, or Heavenly Guard Kick—
Kakashi picked them up instantly, often after just one demonstration.
Even Tsunade, who had seen countless prodigies, found herself speechless at his speed.
After a long period of consideration, Tsunade decided to go all in—
She would teach him her forbidden techniques:
Ninja Art: Mitotic Regeneration, and the Hundred Healings Technique.
But first, he had to master the Hundred Healings Mark.
Which brought us to the current scene.
---
"The sealing technique for the Hundred Healings Mark is way too complicated!"
Kakashi groaned as he massaged his temples.
When he first received the secret scroll, he had been ecstatic.
After all, this was the main reason he chose Tsunade as his mentor.
But upon opening it…
He was buried beneath hundreds of densely packed pages, each covered in seals, formulas, and handwritten annotations.
It felt like someone had dumped an entire library on his head.
"This is absurd… there are hundreds of seals in here. When am I supposed to finish this?"
Kakashi wanted to scream.
The Hundred Healings Mark had been developed by Uzumaki Mito, the wife of the First Hokage.
As the culmination of the Uzumaki Clan's legendary sealing arts, it was insanely complex.
But Tsunade had assured him that he didn't need to understand it all.
He only had to imitate—
Using a miniature rune-reduction technique, he had to copy each symbol onto his body in the correct sequence.
It sounded simpler in theory. But in practice?
Kakashi could only rely on his own two hands.
He had begged Tsunade to at least show him a demonstration—but was flatly denied.
She claimed it was a necessary step in his growth.
But judging by the smug grin on her face…
Kakashi was pretty sure she just wanted payback for all the times he'd embarrassed her with his monstrous learning speed.
Still, Kakashi wasn't someone who gave up easily.
After lying on the grass in despair for a bit longer, he got back up and resumed his work.
---
To his surprise, the study actually turned out to be rewarding.
The sealing system reminded him of programming code from his previous life.
Miniature runes were reduced to the size of peanuts, yet still maintained clear structures and stability.
The seals were layered together, interconnected to form a solid framework.
Within this complex system, two main functions were embedded:
Energy Storage: Compressing unused chakra into highly concentrated crystals.
Energy Release: Releasing all that stored chakra when needed.
In essence, the technique acted like a chakra battery.
Thankfully, he didn't have to worry about high concurrency or real-time server crashes, Kakashi joked inwardly.
But the more he studied, the more impressed he became.
The scroll included advanced techniques such as the Four Symbols Seal, one of the core formulas of the Uzumaki Clan.
And these weren't just random scribbles.
They were high-tier sealing jutsu—
The kind that could one day evolve into something like Adamantine Sealing Chains or even Six Paths: Chibaku Tensei.
Of course, those required either Uzumaki blood or Six Paths power—
Kakashi had neither. But just learning the foundations could push his abilities to a whole new level.
Reinvigorated, he dove back into the scrolls with renewed purpose.
---
One month later.
Tsunade's eye twitched as she watched Kakashi approach her.
His silver hair was a mess. His eyes were bloodshot.
But more importantly—
A diamond-shaped seal glowed faintly on his forehead.
He had done it.
Even Tsunade, who had learned it herself, was taken aback.
She had taken over two months—and even then, she had skipped studying often to gamble.
But Kakashi?
He finished it in a month. And he hadn't even cheated.
This kid was terrifying.
"Well," she said slowly, trying not to let her pride show,
"It seems you've successfully mastered the Hundred Healings Mark."
"In that case, it's time I teach you my ultimate techniques:
Forbidden Technique: Ninja Art—Mitotic Regeneration and
Forbidden Technique: Hundred Healings."
"Rin, come over here," she called to the girl training nearby.
"Shizune already knows these, even though she never mastered them.
You both need to listen carefully."
---
Tsunade stood tall as both Kakashi and Rin gathered in front of her.
"The Ninja Art: Mitotic Regeneration uses the chakra stored in the Hundred Healings Mark to accelerate cellular division.
It rapidly regenerates damaged organs and tissues, even during battle."
"The technique automatically adjusts how much chakra is used, based on the severity of the injury.
However, be warned—cells can only divide so many times. Overuse will shorten your lifespan."
"On the other hand, the Hundred Healings Technique unlocks the full power of the seal.
The chakra spreads throughout the body, amplifying all your physical abilities."
"While in this state, Mitotic Regeneration becomes passive.
Whenever you're injured, it automatically kicks in and heals you instantly."
"This means you can fight non-stop.
Your Super Strength and Heavenly Guard Kick will be doubly powerful."
Kakashi and Rin's eyes widened in awe.
Then Tsunade's expression turned solemn.
She took a step forward.
"Now, watch carefully as I demonstrate."
---
"Hundred Healings Mark—Release!
Ninja Art: Mitotic Regeneration!"
A purple light burst from the diamond on her forehead.
With it, dark markings spread across her face.
"Forbidden Technique—Hundred Healings!"
The curse marks extended beyond her face—down her arms, torso, and legs—until they enveloped her entire body.
A powerful aura erupted around her, sending a shockwave through the forest.
"Remember these core medical ninja rules!" she shouted.
"First! Never stop treatment until your teammate is truly dead!"
"Second! A medical ninja must never fight on the frontlines!"
"Third! A medical ninja must not die before any of their team!"
"Fourth! Only those who have mastered both Mitotic Regeneration and the Hundred Healings Technique may break all three rules!"
---
Kakashi and Rin stood frozen in place, eyes wide with admiration.
So this was the strength of a top-level medical ninja…
So overwhelming. So awe-inspiring.
From this moment on, Kakashi's journey into forbidden healing techniques had truly begun.