The realization came to Kenjaku three weeks after his battle with Sukuna, during a routine meditation session in his Uzushio quarters.
He had won against the King of Curses. Had sealed away the most dangerous techniques of the most powerful being in jujutsu history. Had accomplished something that generations of sorcerers had deemed impossible.
And he had nearly died doing it.
The memory of those desperate moments replayed in his mind with uncomfortable clarity. Sukuna's casual dismissal of his attacks. The overwhelming speed that had made evasion almost impossible. The raw power differential that had reduced all of Kenjaku's centuries of experience to mere survival instinct.
He had won through cleverness, through surprise, through techniques that Sukuna had never encountered and couldn't defend against. But cleverness had limits. Surprise could only work once. And there were beings in this merged world who wouldn't be caught off guard so easily.
Madara Uchiha, who would eventually awaken the Rinnegan and challenge the very concept of mortality.
Obito Uchiha, who would manipulate the shinobi world from the shadows while wielding Kamui's untouchable intangibility.
Hashirama Senju, whose Wood Release could suppress even tailed beasts and whose vitality made him nearly unkillable.
Kaguya Otsutsuki, the progenitor of all chakra, a goddess who had been sealed rather than killed because killing her was beyond the founders' power.
The other Otsutsuki, an entire clan of dimension-hopping parasites who viewed planets as fruit to be harvested.
The Akatsuki, a collection of S-rank missing-nin whose members included immortals, puppet masters, and living explosives.
Naruto Uzumaki, who would eventually contain the full power of all nine tailed beasts and achieve a form of godhood through sheer determination.
Sasuke Uchiha, whose Eternal Mangekyo Sharingan and Rinnegan would make him one of the most versatile combatants in history.
And somewhere out there, Sukuna was still alive, still plotting, still burning with hatred that would eventually demand satisfaction.
Kenjaku had entered this world believing himself powerful. The Sukuna fight had taught him the truth.
He was strong. But he was not strong enough.
Not yet.
The training began the next morning.
Kenjaku approached his physical development with the same methodical intensity he applied to everything else. Centuries of existence had given him vast experience with different bodies, different capabilities, different limits. He understood anatomy at a level that most medical professionals never achieved. He knew exactly how far he could push flesh and bone before they broke.
And with Idle Transfiguration, he could reshape that flesh and bone to exceed normal human parameters.
The first phase focused on baseline enhancement. Every morning, Kenjaku would use his technique to optimize his body's physical structure—strengthening muscle fibers, reinforcing bone density, improving neural conductivity. The changes were small individually, but they accumulated rapidly.
Within a week, his speed had increased by twenty percent. His strength by fifteen. His reaction time had sharpened to levels that approached the legendary shinobi of canon.
But physical enhancement alone wasn't enough.
"You're pushing too hard," Hiroshi observed one afternoon, watching Kenjaku perform training exercises that would have killed an ordinary person. "Your body is remarkable, but even remarkable bodies have limits. You'll destroy yourself at this rate."
"Limits are meant to be broken," Kenjaku replied, not pausing in his routine. "And destruction can be reversed, as long as I maintain consciousness."
He finished a set of movements that had left his muscles screaming and his lungs burning, then immediately used Idle Transfiguration to repair the damage. The technique couldn't heal in the traditional sense, but it could reshape his body back to an optimal configuration, effectively resetting the physical trauma.
"That's cheating," Hiroshi said, though his voice carried more fascination than disapproval.
"No. It's efficiency." Kenjaku began another set, pushing even harder than before. "Normal training works by damaging the body and allowing it to rebuild stronger. I'm simply accelerating the process—applying damage and repair in rapid succession, forcing adaptation at a rate that natural healing could never match."
The approach was brutal but effective. Every session left Kenjaku operating at the absolute edge of his physical capabilities, then reshaped him to slightly exceed those capabilities before the next session began. It was an exponential growth curve, limited only by his cursed energy reserves and his willingness to endure constant, deliberately induced suffering.
He was very willing.
Hana watched his training with a mixture of awe and concern. Her own development had been progressing steadily under Kenjaku's guidance, but the gap between them was widening rather than narrowing. Every day, her master became something more—something further from human, something that defied the categories she understood.
She found it intoxicating.
"Master," she said one evening, after a particularly grueling session had left Kenjaku temporarily immobile while his body reconfigured, "why are you pushing so hard? You defeated Sukuna. You're already the strongest being I've ever seen."
"Sukuna was one opponent." Kenjaku's voice was strained from exertion, but his mind remained sharp. "And I barely survived that encounter. What happens when I face two such opponents? Or ten? What happens when I confront beings whose power dwarfs even the King of Curses?"
Hana's brow furrowed. "Are there such beings?"
"There will be." Kenjaku allowed his body to finish its current reshaping cycle, then sat up with renewed energy. "The future holds threats that this era cannot imagine. Entities that make Sukuna look like a talented amateur. I've seen glimpses of what's coming, Hana. And if I'm not ready—if I haven't transcended every limit this body can achieve—then everything I'm building will be swept away like sand before a tsunami."
He met her eyes with an intensity that made her breath catch.
"I refuse to let that happen. I will become strong enough to face anything this world produces. Strong enough to challenge gods themselves. Whatever it takes. However long it takes. However much it costs."
Hana saw the absolute conviction in his gaze and felt her devotion deepen further. This was why she followed him. This was why she had surrendered everything she was to his service.
He was reaching for heights that no one else could even perceive.
And she would do anything to help him get there.
The second phase of Kenjaku's training focused on cursed energy development.
Raw physical power was important, but in a world where spiritual energy determined the outcome of most conflicts, it was ultimately secondary. Kenjaku needed to expand his cursed energy reserves, refine his control, develop new techniques that would give him advantages against opponents he couldn't simply overpower.
The Uzumaki sealing knowledge provided the foundation. Their tradition included meditation techniques designed to expand spiritual capacity—methods that shinobi used to increase their chakra reserves over time. Kenjaku adapted these approaches for cursed energy, combining them with jujutsu principles to accelerate development.
But adaptation wasn't enough. He needed innovation.
The breakthrough came during his third week of intensive training, while experimenting with the interaction between Idle Transfiguration and his own cursed energy production.
Normal cursed energy was generated through negative emotions—fear, hatred, sorrow, pain. The stronger the emotion, the more energy produced. Most sorcerers learned to cultivate controlled negativity, maintaining a baseline of productive emotional darkness without succumbing to the psychological damage it could cause.
Kenjaku had a different idea.
What if he could modify his own soul to produce cursed energy more efficiently? Not through emotional cultivation, but through structural optimization—reshaping the very mechanics of energy generation to exceed normal parameters.
The theory was sound. The implementation was agonizing.
Modifying one's own soul was incredibly dangerous, even with Idle Transfiguration's precision. The soul was the foundation of identity, the core of existence. Changes to its structure could have unpredictable effects on personality, memory, capability. A single mistake could unravel everything Kenjaku was.
He proceeded anyway.
The process took three days of continuous meditation, during which Kenjaku mapped every aspect of his own spiritual structure with painstaking precision. He identified the regions responsible for cursed energy generation, analyzed their function, designed modifications that should theoretically enhance their output.
Then he implemented the changes.
The pain was beyond description—a fundamental violation of his own existence that made physical torture seem like a gentle massage. His consciousness fragmented and reformed multiple times as his soul struggled to adapt to its new configuration. He experienced death, or something close to it, in countless small increments.
But when it was over, his cursed energy reserves had more than doubled.
"Master!" Hana's voice reached him through layers of dissipating agony. She was kneeling beside him, her face pale with fear. "Master, are you—what happened—I couldn't wake you for two days—"
Kenjaku opened his eyes, feeling the power coursing through his modified soul. It was like being born again, his entire spiritual existence humming with potential that hadn't been there before.
"I'm fine," he said, his voice stronger than expected. "Better than fine. I just became significantly more dangerous."
He stood up, testing his new capabilities with small releases of cursed energy. The difference was immediately apparent—greater density, faster recovery, improved efficiency in every technique he attempted.
But more than that, the modification had opened new possibilities. His soul was no longer a static foundation; it was a work in progress, something he could continue refining as his understanding grew.
He could make himself stronger indefinitely.
The limit wasn't his body, or his techniques, or his cursed energy. The limit was his imagination.
And Kenjaku had centuries of imagination to draw upon.
The third phase of training focused on technique development.
Kenjaku's existing abilities were powerful but limited. Cursed Spirit Manipulation let him collect and deploy cursed spirits, but the technique was dependent on finding or creating suitable specimens. Idle Transfiguration gave him unmatched versatility in combat, but it required physical contact for major modifications and consumed significant cursed energy for large-scale changes. His seal techniques were devastating but situational, requiring specific conditions to implement.
He needed more options. More versatility. More ways to respond to threats he couldn't predict.
The Uzumaki library provided inspiration. Their sealing techniques included defensive applications that could be adapted to cursed energy—barriers and shields and reactive protections that would activate automatically when triggered. Kenjaku developed versions of these that could be inscribed on his own soul, creating passive defenses that required no conscious activation.
He called the result Soul Armor.
The technique created multiple layers of spiritual protection, each designed to counter different types of attacks. Physical strikes would be partially absorbed, reducing their impact. Spiritual attacks would be redirected, their energy channeled away from vital aspects of his existence. Even soul-targeting techniques—like his own Idle Transfiguration—would face resistance, the inscribed seals fighting against external modification.
It wasn't invincibility. Nothing was. But it was a significant improvement over his previous vulnerability.
Beyond defense, Kenjaku developed offensive applications for his combined traditions. He created cursed energy constructs reinforced with sealing patterns, making them more durable and precise than normal projections. He refined his Maximum: Uzumaki technique, incorporating seal-enhanced focusing to dramatically increase its destructive potential. He experimented with barrier techniques that could trap opponents in spaces where his advantages were maximized.
Each new development was tested in combat against the hostile forces that the Warring States Period provided in abundance. Bandits, rogue shinobi, minor clan patrols that strayed too close to his training grounds—all became unwitting test subjects for his evolving capabilities.
The results were encouraging.
Opponents who would have posed genuine challenges a month earlier now fell within seconds. Kenjaku's combat efficiency had improved by an order of magnitude, his expanded cursed energy reserves allowing sustained engagements that would have previously exhausted him. His physical enhancements made him faster and stronger than most shinobi could track, while his new defensive techniques made him almost impossible to damage.
But it still wasn't enough.
Because every improvement Kenjaku made was measured against the threats he knew were coming. And those threats weren't bandits or rogue shinobi or minor clan warriors.
They were gods.
"Tell me about the Uchiha," Kenjaku instructed Hana one evening, after a training session that had left a small army of bandits scattered across the landscape like broken toys.
Hana had been observing his growth with something approaching religious reverence, her devotion now so complete that she no longer even attempted to maintain professional distance. She responded to his question immediately, pulling from the intelligence she had gathered during their time on Uzushio.
"The Uchiha are one of the most powerful clans in the current era. They're known for their Sharingan—a dojutsu that grants enhanced perception, the ability to copy techniques, and in rare cases, access to powerful genjutsu. They've been at war with the Senju clan for generations."
"Their current leadership?"
"Uchiha Tajima is the clan head. He has several children, including two sons who are reportedly prodigies—Madara and Izuna. The older one, Madara, is supposedly the most talented Uchiha in living memory."
Kenjaku nodded, already knowing far more about Madara than Hana could possibly report. The boy who would become the legendary ghost of the Uchiha, whose hatred would shape shinobi history for generations, was currently just a child—probably around ten years old, developing the skills that would eventually make him a living legend.
It would be easy to kill him now. A single assassination, targeting a child who hadn't yet developed the power to defend himself. Madara's future influence would be erased before it began.
But that wasn't what Kenjaku wanted.
"And the Senju?" he prompted.
"Equally powerful, with a bloodline that grants exceptional vitality and life force. Their current head is Senju Butsuma. His sons—Hashirama and Tobirama—are considered the heirs apparent. Hashirama in particular is rumored to have developed a unique ability, though details are scarce."
Wood Release. The power that would eventually suppress tailed beasts and build hidden villages from nothing. Currently manifesting in a child who dreamed of peace, who would one day become the God of Shinobi.
Another easy target. Another assassination that could reshape history.
Another option that Kenjaku rejected.
Because killing Madara and Hashirama before they reached their potential would defeat the entire purpose of his existence in this world. He wasn't here to prevent threats—he was here to face them. To test himself against the greatest beings this merged universe could produce. To prove that his vision, his preparation, his relentless self-improvement could triumph over any opposition.
What glory was there in murdering children? What satisfaction in erasing legends before they could be born?
No. Kenjaku wanted to fight Madara at his peak. Wanted to challenge Hashirama when Wood Release had achieved its full expression. Wanted to face every threat this world could generate and emerge victorious through power rather than prevention.
That was the story he was writing.
"Continue monitoring the major clans," he told Hana. "I want to know about every significant development—political marriages, deaths, emerging talents, shifting alliances. The more we understand about the current landscape, the better positioned we'll be to influence the future."
"Understood, Master." Hana hesitated, then asked the question that had clearly been building in her mind. "What exactly are we working toward? You've mentioned shaping the future, influencing the transition to a new era. But what does that mean specifically?"
Kenjaku considered how much to reveal. Hana's loyalty was absolute, but her understanding was limited. She didn't have the meta-knowledge that allowed him to see the larger patterns, the eventual developments that would reshape this world.
"Do you know what a hidden village is?" he asked.
Hana shook her head.
"It doesn't exist yet. But it will." Kenjaku gazed into the middle distance, seeing futures that hadn't been written. "Eventually, the endless warfare of this era will exhaust everyone. The clans will realize that their current model—small family groups fighting for scraps of territory—is unsustainable. Someone will propose an alternative: larger organizations, combining multiple clans under unified leadership, establishing territories and treaties that make constant warfare unnecessary."
"That sounds... impossible," Hana said. "The hatred between clans runs too deep. The Uchiha and Senju alone have been killing each other for so long that neither side can imagine peace."
"And yet peace will come. Because the alternative is extinction." Kenjaku's smile carried an edge of prophetic certainty. "Hashirama Senju will dream of a village where children don't have to die on battlefields. Madara Uchiha will be convinced—temporarily—that cooperation could protect what remains of his family. Together, they'll create the first hidden village, and others will follow their example."
He turned to face Hana directly.
"That transition is the moment when I can exert maximum influence. If I position myself correctly, I can shape the structure of the new order. Determine which clans rise and which fall. Establish power bases that will persist for generations. Plant seeds that won't bear fruit for decades but will eventually reshape the entire shinobi world."
Hana absorbed this information with visible wonder. "You can see the future?"
"Not exactly. I understand the forces that will shape it." Kenjaku's answer was technically honest while obscuring his meta-knowledge. "The patterns of history repeat. The drives that motivate people—survival, power, connection, legacy—remain constant across eras. If you understand those drives well enough, prediction becomes possible."
"And what do you want from this future you're shaping?"
The question was more perceptive than Kenjaku had expected from his obsessively devoted subordinate. It deserved a genuine answer.
"I want to be necessary," he said. "I want to be a force that cannot be ignored, whose influence touches every significant event. I want to build something that will endure for centuries—not a kingdom or an empire, but a legacy. A mark on history that proves I existed, that I mattered, that the world would have been fundamentally different without me."
He paused, considering his deeper motivations.
"In my previous existence, I was nobody. A forgettable person living a forgettable life, contributing nothing of value to a universe that wouldn't notice my absence. This world—this opportunity—is my chance to be someone. To write a story worth remembering. To become the villain that legends will be told about for generations."
Hana's expression softened with something that might have been compassion, if her emotional responses hadn't been so thoroughly warped by her attachment.
"You're not nobody, Master. You're the most extraordinary being I've ever encountered."
"Now I am." Kenjaku's smile returned, self-aware and slightly mocking. "But I wasn't always. And the fear of returning to that state—of becoming ordinary, irrelevant, forgotten—drives me more than any specific ambition. I would rather be history's greatest monster than one of its countless anonymous victims."
He stood up, signaling the end of their conversation.
"That's why I train. That's why I prepare. That's why I will never stop improving, never stop reaching for greater power. Because the alternative is unacceptable."
The weeks continued to pass, each one bringing new developments in Kenjaku's capabilities.
His physical training had reached a plateau—not because he couldn't improve further, but because additional modifications required understanding he hadn't yet developed. The body he inhabited had been pushed to its theoretical maximum. Going further would require insights into human biology that exceeded even his extensive knowledge.
But his cursed energy development showed no such limitations. Each refinement to his soul's structure increased his reserves further, and the compound effect was becoming dramatic. By the third month of intensive training, Kenjaku's cursed energy capacity exceeded what he had possessed at his peak in the original timeline—and he was still growing.
His technique arsenal had expanded substantially as well. Soul Armor had been refined through dozens of iterations, each version more sophisticated than the last. His barrier techniques had been integrated with Uzumaki sealing methods, creating defensive structures that could contain even S-rank threats for significant periods. His offensive capabilities had been diversified to handle different types of opponents, with specialized approaches for physical fighters, spiritual attackers, and technique-based combatants.
And throughout all of this development, Kenjaku maintained his cover as a visiting scholar, sharing enough knowledge with the Uzumaki to keep them invested in the relationship while concealing his true capabilities.
It was exhausting. It was exhilarating. It was exactly what he needed.
But as his power grew, so did his awareness of how much further he still had to go.
Madara's eventual Rinnegan would allow him to control the Gedo Statue and, through it, the Ten-Tails. Even with Kenjaku's current abilities, he wasn't confident he could defeat that level of threat.
Obito's Kamui would make him essentially untouchable during its activation. Kenjaku needed a counter-technique, something that could bypass intangibility.
Hashirama's Wood Release could suppress cursed energy just as effectively as it suppressed tailed beast chakra. The interaction between their abilities was unpredictable and potentially dangerous.
Kaguya was a goddess with thousands of years of existence and power that transcended mortal understanding. Defeating her might require alliances, preparations, resources that Kenjaku hadn't yet begun to accumulate.
The other Otsutsuki were unknown quantities, their capabilities potentially exceeding anything this planet had produced.
And Sukuna was still out there, still sealed but still alive, still nursing a hatred that would eventually demand satisfaction.
The threats were overwhelming. The timeline was uncertain. The challenges ahead were beyond anything a normal person could imagine facing.
But Kenjaku was no longer normal.
He was something ancient wearing something young, carrying knowledge of futures that might never come to pass. He was a monster by choice, a villain by design, a force of chaos and ambition that would not be denied.
And he was getting stronger every single day.
"Again," he told Hana, as they faced each other in the training ground they'd established outside the Uzumaki village. His subordinate had improved dramatically under his instruction, her combat capabilities now exceeding most jonin-level shinobi. But she was still no match for him.
That was the point.
Training against inferior opponents forced him to develop restraint, control, precision. It wasn't about winning—he could win instantly, at any time. It was about winning while maintaining specific limitations, about achieving objectives with minimum expenditure of resources.
Because someday, he would face opponents where efficiency would mean the difference between victory and defeat.
Hana attacked with everything she had—a combination of taijutsu, weapons, and the basic cursed energy manipulation Kenjaku had taught her. Her movements were fast, fluid, the product of intensive training and absolute dedication.
Kenjaku countered everything without moving from his spot, using minimal cursed energy to deflect each attack. His perception had sharpened to the point where Hana's movements seemed almost slow, predictable patterns that he could read before they fully formed.
"Your left side is exposed," he observed, during a brief pause in the assault. "You're favoring your right leg after the injury last week. Compensate consciously until the habit is corrected."
Hana adjusted her stance immediately, attacking again with improved form. Her devotion made her the perfect student—she accepted criticism without ego, implemented corrections without resistance, pushed herself beyond her limits without being asked.
It was almost too easy.
Kenjaku deflected another series of attacks, his mind wandering to larger concerns even as his body maintained perfect defensive awareness.
The future was approaching. The children who would become legends were growing older, developing their powers, moving toward the destinies that would reshape the world. Every day brought them closer to the peak capabilities that Kenjaku would eventually face.
He needed to be ready.
He needed to be stronger than anything this universe could produce.
He needed to break every limit, exceed every expectation, become something that even gods would fear.
And he would.
Because that was the only acceptable outcome.
That was the story he was writing.
And the villain always prepared for the final battle.
The training session ended with Hana's defeat—inevitable, but achieved through her absolute exhaustion rather than any dramatic finishing move. Kenjaku caught her as she collapsed, lowering her gently to the ground.
"You're improving," he told her. "Another month at this pace, and you'll be able to challenge most elite shinobi."
"Still nothing compared to you," Hana murmured, her voice thick with fatigue and adoration.
"No. But you're not supposed to compare yourself to me." Kenjaku brushed hair from her face, the gesture almost tender. "Your role is to be useful, not to be equal. And you're becoming very useful indeed."
Hana smiled, her exhaustion somehow deepening her contentment. Being useful to him was the only purpose that mattered.
Kenjaku lifted her and began walking back toward the village, his enhanced body showing no strain from her weight. The sun was setting over Uzushio Island, painting the sky in shades of red and gold.
Somewhere on the mainland, the Warring States continued. Clans fought and died. Children grew into warriors or corpses. The future Kenjaku had seen in manga panels and anime episodes was being written in blood and fire.
And at the center of it all, invisible but influential, the greatest villain of the age continued his preparations.
Breaking his limits.
Exceeding his potential.
Becoming something that had never existed before.
Something that the world would remember forever.
Whether it wanted to or not.