Due to the unique nature of the Uchiha clan's kekkei genkai...
Their study of Yin Release techniques and training methods had always held a significant advantage. Thanks to the Sharingan, they could explore spiritual energy far more easily than others.
The relationship between kekkei genkai and secret techniques was mutually reinforcing. The bloodline ability made it easier to develop secret arts, while the techniques in turn strengthened their mastery of the kekkei genkai.
This feedback loop was the true reason why the Uchiha clan was able to pull so far ahead of other shinobi.
It was hard to believe that Sasuke, the clan leader's son, wouldn't know the methods of cultivating Yin Release.
Fugaku, as portrayed in the original story, always had high expectations for both his sons. He even brought a four-year-old Itachi onto the battlefield—clearly wanting to pass on everything he could as early as possible.
And yet, Sasuke showed little noticeable progress up until the age of twelve. It was obvious: either he lacked proper guidance, or Konoha had withheld too much of the Uchiha's inheritance.
As a result, Sasuke was stuck refining the same basic techniques over and over again—unable to advance without a proper teacher.
That thought led Kaien to recall the "inheritance" his cheap parents had left him.
If he hadn't chosen to become a shinobi, he probably wouldn't even be able to spend all of it in a lifetime.
Back to the matter of the Sharingan—
There were only two real explanations for why Sasuke didn't realize he had awakened it.
One: Itachi had cast a genjutsu on him, making him subconsciously forget the event of awakening.
Otherwise, how could the sudden surge in chakra and ocular power that came with awakening the Sharingan go unnoticed?
The second possibility: it was Indra's chakra activating a protective mechanism—delaying early development to store up latent potential, allowing for a rapid bloom during growth.
Kaien had neither of these conditions.
No older brother with blood ties, no chakra from a legendary figure to watch over him.
All he could do was follow the honest, brutal path—where even a genius could die young if fate willed it.
It was a strange feeling.
To have so much power... and yet still feel a hollow emptiness inside.
Perhaps that was why Kaien often seemed lethargic, unmotivated on the surface.
Only when he fought seriously did the sharp edge of his Uchiha genius show.
"Yeah, things are kind of grim right now... but it's nowhere near hopeless. Worst case, when my Mangekyō awakens, I'll just keep focusing on healing my kekkei illness!"
The Sharingan is a reflection of the soul. Kaien refused to believe that such a strong will to live wouldn't manifest as a life-saving ocular ability.
Still, speaking of the Sharingan—
Kaien realized something strange.
He had already tested the ability to suppress the scarlet glow of the Sharingan. That worked before.
But now, with the newly acquired [Weakness Camouflage] trait, there might be even more possibilities.
Take now, for instance—
Kaien watched as the tomoe in his eyes changed form before his very eyes—three tomoe faded to two, then one... and then suddenly morphed into the four-bladed pinwheel of the Mangekyō Sharingan.
The form of Kamui's Mangekyō.
"Even though I can change the appearance of my Sharingan... the power remains that of a three-tomoe. Disguising it as Mangekyō doesn't make it real…"
Still, [Weakness Camouflage] was far more useful than he'd initially thought.
Being able to mask the form of the Sharingan? That was an unexpected bonus.
Turning his real three-tomoe into a fake one-tomoe wasn't just harmless—there was genuine value in it.
Finally... he could use the Sharingan openly in front of others.
A seven-year-old with a one-tomoe Sharingan would still turn heads.
But he was Orochimaru's disciple, a recognized Uchiha genius, and someone who had experienced loss.
No one would question it too much if he awakened a one-tomoe Sharingan, right?
Besides, he had protection.
One of the two people in the world who coveted the Sharingan most was now his own teacher.
And this could be the perfect way to get Orochimaru invested in researching his bloodline illness.
If Kaien wanted his help, he needed a good excuse.
Back when he only had the two-tomoe, he didn't dare show it.
But with just one tomoe? That was safe.
At worst, he'd be labeled a genius.
Not a freak.
And as long as he didn't channel chakra into the eye, no one could tell it wasn't a genuine one-tomoe.
The tragic tale of a beautiful young genius, falling ill after awakening his Sharingan...
There was no way Orochimaru—especially this version of Orochimaru, still retaining a trace of humanity—could stay indifferent.
And on top of that... he could milk some sympathy out of the lambs watching from afar.
Kaien smiled warmly—genuinely, for once—as his thoughts settled.
Then he used the Summoning Technique and called forth a black cat to use as a pillow.
The black cat was a member of the ninja cat clan.
Over the past year, Kaien had built a solid relationship with it. A few dried fish was all it took for a fluffy pillow and a personal sentry.
Too convenient to pass up.
...
"Kagami, thank you for your hard work."
Hiruzen Sarutobi looked at the man in front of him—Uchiha Kagami—who, despite being younger, now carried an air of deep weariness.
Kagami hadn't returned to Konoha in over a year.
This was his first time back.
While investigating the mysterious deaths of Kaien's parents, he was suddenly ambushed.
Had it not been for the power of his Mangekyō Sharingan, Kagami truly believed he would've died there.
He recovered in secret, then rushed straight to the Land of Whirlpools the moment he received Hiruzen's message.
The constant traveling had drained the naturally-curly-haired Uchiha to his limits.
Kagami first gave a report on everything he had uncovered in the Land of Iron, then moved on to his analysis of the Land of Whirlpools.
"These two incidents may seem unrelated on the surface… but I can't shake the feeling that there's a single hand orchestrating everything from the shadows."
"And whoever they are, their target is clearly Konoha."
"If we lose our allies, Kirigakure could strike deep into our territory. And Kumogakure has been circling like a vulture…"
Kagami's expression darkened. A single misstep could plunge the shinobi world into another war.
After years of recuperation, all five great nations now had the strength to wage war again.
Hiruzen fell silent as well.
Clack, clack—
The soft knock of his pipe against the wooden desk echoed in the room.
"I'll take care of everything. For now, you need to rest, Kagami."
He looked at the Uchiha's tired face, concern in his eyes.
"I couldn't uncover the truth… How can I face that child?"
Kagami's voice was bitter.
Even with eyes that surpassed the power of a three-tomoe Sharingan… there were still things beyond his grasp.
"This wasn't your failure, Kagami."
"And... that child is now under Orochimaru's wing."
"He's found a new bond. He's a boy who draws out the deepest pity from the hearts of others…"
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Pls Drop some Power Stones
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