The sky was a vibrant blue, with towering clouds drifting like mountains. A gentle breeze pushed the cloudscape along, casting shifting patterns of light and shadow across the forest floor, drawing a clear line between the boy and girl standing there.
The handsome boy stood in the light, his crimson eyes gleaming with an eerie intensity, his spiky hair casting sharp, jagged shadows on the ground.
The silver-haired blind girl stood in the shadow of the clouds, her luminous skin radiating a captivating glow in the dim environment.
It was a picturesque scene—one that could make a jaded middle-aged man reminisce about his youthful days or inspire a lovestruck teenage girl to weave countless romantic tales, her eyes sparkling with emotion.
But reality was far less poetic.
"The Thunder Blade: Fang is a legendary ninja tool from the Mist Village. It amplifies Lightning Release, boosts casting speed, reduces chakra consumption, and can even summon natural lightning for combat. It's not something Zabuza's clunky cleaver could ever compare to. Among the Seven Ninja Swords of the Mist, the Thunder Blade is a contender for the strongest ninja tool. For a ninja skilled in Lightning Release and swordsmanship, it's practically priceless!"
A shadow clone researching the Thunder Blade relayed its findings to Hikari, who, with her eyes closed, enthusiastically described the blade's capabilities to Sasuke.
As she absorbed the clone's memories, images of experiments and analyses flooded her mind, deepening her awe of the blade's power. The Thunder Blade, or Thunder Fang, had an exceptionally high chakra metal content. As a dual-wielded weapon, its craftsmanship alone was exorbitantly expensive. The intricate Lightning Release seals etched into it were so sophisticated that even Hikari was impressed.
No hand signs needed for Lightning Release, faster casting, doubled power, halved chakra cost—it was essentially a lightning staff in the form of dual blades!
Hikari wasn't exaggerating in the slightest.
While Samehada might edge it out slightly in versatility, their offensive capabilities weren't even in the same league. In the hands of a Lightning Release master, this blade could rightfully claim the title of the strongest ninja sword.
Sasuke's eyes, with their spinning tomoe, glinted with a faint red glow as he listened, clearly determined to claim the weapon.
"Its value as a test subject pales in comparison to this ninja tool—unless…" Hikari said with a sly smile, watching Sasuke's serious expression. "You're willing to join my organization."
"Your organization?" Sasuke's brow furrowed. Despite knowing her for years, he'd never heard of Hikari being part of any group.
"I can't reveal the organization's name yet, but if you agree to join and carry out assigned missions while allowing our researchers to study the evolution of your Sharingan, you'll get the Thunder Blade!"
Hikari laid out her true intentions.
She had no one she truly trusted in Root. Ryoma, who'd betrayed her, could no longer be relied upon. Chihaya and Iwakuma, while capable, were old friends of Ryoma and former subordinates of Danzo, so she remained wary of them. Most critically, Root lacked high-end combat power besides her.
There were a few Jonin, but in the increasingly chaotic ninja world, Jonin were barely better than cannon fodder. Younger members like Sai and Torune Aburame had potential but clear limits—they could be useful but couldn't carry the team.
Sasuke was different.
After five years of close companionship, his arrogance had been tempered. With Naruto, Guy, Kakashi, and others by his side, he wasn't the dark, isolated figure from the original story. Danzo, the mastermind behind the Uchiha massacre, was a wanted criminal in Root, and Hikari was the one who'd driven him out of Konoha—a benefactor in Sasuke's eyes. His personality made betrayal unlikely.
As for his potential? That was a no-brainer.
Once he stabilized his three-tomoe Sharingan, he could seek out a dying Itachi to awaken the Mangekyo Sharingan, then use Itachi's eyes to achieve the Eternal Mangekyo. With a fully realized Susanoo, he'd rocket straight to Kage-level strength.
Root needed talent like that.
The clouds drifted with the wind, and the shadowy waves at Hikari's feet crept toward Sasuke.
Her conditions were harsh. Sasuke's chest heaved, his tomoe spinning as he weighed the pros and cons, silent for a long moment. He trusted Hikari enough to be a test subject, but joining an organization and taking on mysterious missions while having his Sharingan studied was practically signing his life away.
"I'd be your only superior in the organization, and you'd only need to follow my orders," Hikari explained patiently, her eagerness to recruit mirroring Danzo's in the past.
Once a top enforcer in Root, now its leader, she naturally needed capable ninjas who could fight.
Sasuke's expression didn't change, but the resistance in his emotional aura noticeably lessened.
There was hope!
Noticing his shift, Hikari pressed on, her excitement growing. "Join the organization, and I'll help you awaken a Sharingan beyond the three-tomoe!"
Flash!
A spark seemed to ignite in Sasuke's eyes, his face brimming with uncontainable shock. "A Sharingan beyond the three-tomoe? That's right—Itachi's eyes…"
He muttered, memories of that haunting night flooding back. Amid the endless pain, he recalled the spinning black shuriken in Itachi's strange Sharingan. If he could evolve his Sharingan to that level, he could take on Itachi and avenge his parents and clan.
A flame of vengeance blazed in Sasuke's chest—not just raw anger but a colder, heavier resolve, far more intense and complex than mere killing intent.
"I'm in!" Unable to resist Hikari's offer, Sasuke locked eyes with her and vowed, word by word, "As long as you give me the power to take revenge, you can have anything you want!"
"I want your loyalty!" Hikari raised her right hand, her index and middle fingers together, a purple glow igniting at her fingertips.
Seeing the gesture, Sasuke's heart jolted. It was identical to one he knew all too well—Itachi's!
Rage surged, nearly overwhelming his reason. The two tomoe in his left eye spun wildly, forming a black ring, with a third tomoe faintly taking shape.
The evolution interrupted in the Land of Waves was reignited by this sudden trigger!
Was he evolving already?
Hikari raised an eyebrow, too caught off guard to marvel at Sasuke's sensitivity. Seizing the critical moment of his Sharingan's evolution, she activated her Byakugan's pupil power, invading his mind.
She immediately saw a surge of Yin Release chakra, brimming with intense emotion, flowing from his pineal gland.
That was it!
Her Byakugan glowed as she locked onto Sasuke's forehead. The chakra surged toward his left eye, and in an instant, the third tomoe fully formed.
"I—evolved?" Sasuke, still burning with anger, noticed the world sharpening around him. Even Hikari's hair, swaying in the wind, seemed to move in slow motion. His chakra surged with the evolution of his Sharingan.
Having experienced this once before, he instantly realized he'd achieved the three-tomoe Sharingan he'd been chasing!
The joy of growing stronger broke through his emotions. The special energy from his pineal gland abruptly stopped, the spinning tomoe slowed, and his eyes stabilized—three tomoe in the left, two in the right, a striking contrast.
"Congrats," Hikari said, observing the process but feeling puzzled. She couldn't understand how that unique chakra was generated.
There was no fusion of mental and physical energy like normal chakra, no special process. Neither the pineal gland nor the brain showed any unusual structure.
The Sharingan's evolution seemed to rely solely on intense emotion to spontaneously create this special chakra. That wasn't ninja-like at all! Even the Otsutsuki needed the God Tree to absorb natural energy for chakra—creating it from nothing was impossible.
It defied the fundamental logic of chakra, yet the Sharingan's evolution challenged the entire ninja world's system.
Lowering her hand, Hikari stubbornly continued observing, scanning every cell in Sasuke's pineal gland where the chakra originated. Her pupil power drained rapidly, her forehead aching.
No matter how closely she looked, she couldn't find the chakra's source. His brain had no abnormal structures, and the chakra's emergence was bizarre, as if the Yin Release chakra existed all along, hidden in a dimension like Kamui, unlocked only by extreme emotion as a key.
The pineal gland was like a signal transmitter to that dimension!
Could that emotionally charged chakra be… Indra's chakra?
The thought struck Hikari, but she quickly dismissed it. The Second Hokage had dissected Uchihas—surely they weren't all Indra reincarnates. Itachi and Obito's Sharingan evolutions also relied on emotion. If it was all Indra's chakra…
Her eyes flickered as information collided in her mind, the unexpected Sharingan evolution revealing shocking secrets.
Seeing Hikari fall silent, Sasuke, reveling in his new power, stood still with wide eyes, letting her observe. Though he'd just agreed to her terms, he was already prepared to be a test subject. Being studied like this, rather than dissected, felt like a steal.
The wind grew stronger in the training field, the clouds shifting to engulf both figures in shadow. Sunlight struggled through the thick clouds, casting faint rays.
Sasuke willingly displayed his Sharingan, not daring to look away, but Hikari didn't acknowledge his cooperation. She was lost in thought about the Uchiha, the Sharingan, and Indra.
Assume the special Yin Release chakra was Indra's power. That raised an unsolvable question: who was the true Indra reincarnate?
The original story gave an answer, but Sasuke's evolution process muddied what seemed obvious. Undisputedly, Madara and Sasuke both achieved the Eternal Mangekyo and were acknowledged by the Sage of the Six Paths as Indra's reincarnates.
A bold theory formed in Hikari's mind: perhaps "reincarnation" was a misleading term. If they were called inheritors of Indra's power, it made sense.
All Uchihas were Indra's descendants, capable of tapping into his power through extreme emotion, making them all inheritors. Sasuke and Madara were special because they accessed a larger share of Indra's power through the Eternal Mangekyo.
Being an "Indra reincarnate" wasn't predestined—it was about being the strongest Uchiha of an era, claiming the most of Indra's power. Only then could one bear the title.
Pondering this, Hikari felt she was close to the truth. Indra was a prideful genius who pursued ultimate personal strength, so only the strongest Uchiha could claim his name. Sasuke and Madara, the greatest of their respective eras, were naturally his reincarnates. If Itachi or Obito had achieved the Eternal Mangekyo first, they could've claimed the title too.
But could Indra's power support four Eternal Mangekyo? Could one Uchiha monopolize so much that others couldn't evolve? Was that why each era typically saw only one Eternal Mangekyo?
Likely, Indra's power could only sustain one Eternal Mangekyo per era, requiring decades or centuries to recover before another could emerge. By then, the previous Uchiha would be dead, leading to the "reincarnation" narrative.
What about Naruto, the Asura reincarnate? Did the strongest Senju or Uzumaki inherit Asura's name through vitality? Hikari shook her head. Aside from the Nine-Tails' power, she'd never seen foreign chakra in Naruto, so she couldn't judge.
Perhaps Asura and Indra's inheritance worked differently, explaining why their reincarnates often clashed.
"Done studying?" Sasuke asked, his crimson Sharingan glaring as he saw Hikari shake her head regretfully. He wasn't a heartless killer, and keeping his eyes open so long was drying them out.
"Pretty much," Hikari replied, licking her back teeth. She'd figured out how to evolve a Sharingan into the Mangekyo.
She couldn't tap into Indra's power herself—only Uchihas, with their millennium-old chakra seed, could. Her only method was to extract the special chakra from Sasuke's pineal gland during an emotional peak and inject it into his Sharingan to trigger evolution. But the resulting Mangekyo would likely still produce Sasuke's Amaterasu and Kagutsuchi.
That was no different from stealing his eyes.
As for the Eternal Mangekyo? Out of the question. Hikari had no Mangekyo-awakened siblings, and draining Sasuke's energy would prevent his own evolution, making the formula impossible.
"You really figured it out?" Sasuke asked, stunned by Hikari's research speed. The Sharingan was an Uchiha bloodline limit—could she really understand it just by observing its evolution?
Rubbing her aching forehead, Hikari didn't want to discuss it with Sasuke, this simultaneously lucky and tragic figure. If her theory about Indra was correct, Sasuke was the ultimate fortunate son.
Indra's power was perfectly restored for an Eternal Mangekyo, his clan was wiped out leaving no competitors, the more talented Obito had no blood-related siblings, and Sasuke had a Mangekyo-awakened brother near death. Everything aligned perfectly, turning the moderately talented Sasuke into Indra's reincarnate.
But thinking of his tragic past, Hikari's envy faded. Perhaps this was the cosmic luck earned by sacrificing his family.
Flash!
Purple flames reignited at her fingertips as Hikari looked at Sasuke calmly. "Pledge your loyalty, and I'll show you the true formula for power!"
Sasuke's expression grew solemn. He removed his Konoha headband, stepped toward Hikari, and saw her raise her hand in that familiar gesture. Brushing his hair aside, he closed his eyes, waiting—
"Stick out your tongue."
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