Uchiha Kiyo was still absorbing natural energy, but this time he maintained strict control, only drawing in what he could purify through his body's transformed structure. The remaining portion of energy required for his body's evolution was supported by the purified natural energy continuously produced by his shadow clones.
This final metamorphosis lasted nearly half a day.
"Finally... the foundation building is complete."
Uchiha Kiyo slowly stood up, feeling the immense power coursing through every inch of his rebuilt frame.
"Ugh, the smell is horrible..."
Just as he was ready to embrace his newfound strength, the stench of decaying necrotic flesh and expelled impurities flooded his senses.
"Water Release: Water Cleansing Technique!"
He formed a few hand signs, and a controlled torrent of water erupted from his palms, cleansing away the foul residue.
"Much better."
Dressed now in a fresh white robe, he took a long breath and focused inward, beginning to analyze the new state of his body.
"The physical improvements are even greater than I expected. The automatic transformation during the spontaneous evolution went far beyond my predictions. The time extension was due to the enhanced structural rebuild. The improvement far surpassed the previous stage."
He spoke softly, his fingers flexing as he studied the subtle but profound increase in strength and control.
"Now my body's compatibility with natural energy has significantly improved. I can purify it at a much faster rate... in fact, I no longer need to pre-store purified natural energy. My body itself can act as a natural filter."
That was the biggest difference. Before, he had to absorb and purify natural energy into storage before using it. But now, his very body served as a high-efficiency purification engine. He could draw in natural energy directly and use it on the spot without any filtration delay.
"Incredible. My chakra refinement speed will increase exponentially. That bottleneck is completely gone."
Beyond that, the quality of his spiritual root had taken another leap forward. During the process of foundation building, his cells had undergone extensive restructuring, incorporating multiple elemental affinities. Among them, Lightning Release stood out—previously a difficult attribute for him to manage, but now successfully integrated.
Although its quality was slightly below his other four primary elements, it was still a breakthrough.
This was true evolution.
While he hadn't completely mastered this newly restructured body, Uchiha Kiyo could already tell that his combat power had at least tripled. Once he adapted fully to his new body and techniques, his overall power would soar even higher.
"So the so-called Foundation Establishment doesn't necessarily require years of preparation. As long as one's natural energy affinity reaches a certain critical point, spontaneous transformation will occur. That seems to be what people mean by opening the Sea of Consciousness."
This meant the method he had used was not the only path. Gradual accumulation of purified natural energy, paired with controlled absorption over time, could also lead to the transformation.
"The Uzumaki Clan would be ideal candidates for this. Their life force is incredibly strong, and they likely possess innate affinity with natural energy. Especially during youth, when cellular division is less active, their affinity consumption would be minimal. Their strong constitution allows for faster absorption of natural energy, and with proper training, they could establish a foundation early."
He paused, thinking deeply.
"Of course, comprehension is key. Even if they aren't proficient in other disciplines, they must at least have strong fundamentals in sealing techniques and basic medical ninjutsu. Thankfully, the Uzumaki have natural talent in both."
What he had achieved today was built upon countless failures and risks, but now, the results were beyond question.
He had also refined his body's transformation method further to maximize efficiency. He was confident this would work for others—especially chosen disciples.
With his fit level nearly perfect, his lifespan would be extended dramatically. This step was crucial to pursuing his longer-term goals.
"The path of immortality truly grants longevity."
The entire system he had constructed was slowly becoming more cohesive. With the successful establishment of the foundation, the cultivation structure was finally beginning to stabilize.
Two realms had now been established—the mortal foundation and the spiritual root—laying the groundwork for a full cultivation system.
But for now, Uchiha Kiyo wasn't ready to re-enter the world. He needed time to synchronize completely with his new strength, recalibrate his techniques, and ensure full mastery of his transformed state.
As he contemplated the future, thoughts of legacy came to mind.
He would need to pass on this knowledge eventually—refining the system until it could be taught. Apprentices. Students. A true legacy.
---
Konoha
When the original body completed its foundation, Hui—the clone stationed in Konoha—instantly received the memory feedback. He and the other clones resumed activity after ensuring the main body was safe.
Though the clones had known that the main body was protected and failure wouldn't end them, there had still been a shadow of anxiety. The foundation stage had taken years of planning.
"With the foundation now established, a lot of our long-term objectives can move forward."
Hui muttered as he walked down the quiet path toward the training grounds.
Through shared memory, he had analyzed the transformation in great detail. The conclusion was clear: the foundation stage couldn't be replicated by clones. Only the original body, with a fully reconstructed structure, could undergo it.
But Hui wasn't discouraged.
"Even if we clones can't achieve foundation building, the immortal cultivation path has been established. The techniques and research can still support the shinobi system. Besides, our current power is more than enough for our objectives."
His eyes wandered to the distance, where three figures trained under the shade of Konoha's morning sun.
It was Team Minato—Kakashi, Obito, and Rin.
They were training on their own today. Minato was out on a mission, leaving the three young genin to handle basic drills and sparring.
Hui observed silently from a distance.
Kakashi, ever serious and composed, executed drills with robotic precision.
Obito, as expected, slacked and complained, throwing himself into half-hearted sparring before arguing with Kakashi.
Rin, on the other hand, trained quietly, her movements full of patience and rhythm. Her control over chakra was impeccable for her age.
Hui's eyes lingered on her.
The idea of taking on a disciple had crossed his mind before, and Rin's aptitude for both medical ninjutsu and sealing techniques made her a perfect candidate.
"Her talent is rare. She may even be able to achieve foundation establishment herself… assuming her 'death' is handled properly."
Hui mused, already calculating timelines and planning fake-death scenarios.
Rin's death was supposed to occur soon in the original timeline, but with the right manipulation, he could fake it. That would allow her to exit the public eye and undergo training in secret.
Meanwhile, Obito was already within reach—both literally and strategically.
A chuckle escaped Hui's lips.
Just then, a shadow stepped beside him.
"How are they doing, Hui-kun?"
It was Namikaze Minato, watching his students fondly.
He had been observing Hui's intense gaze and decided to approach casually.
Hui, already aware of Minato's presence, remained unfazed.
"They're all quite promising. Kakashi's talent is obvious. Obito, while lazy, has the strength and potential. But Rin… Rin is the one with true hidden value. Her chakra control is outstanding, and her medical proficiency already outpaces others in her age group."
Minato gave a quiet nod, his gaze softening.
"Obito worries me. He lacks focus. I often assign Kakashi to provoke him, hoping it'll spark motivation."
He sighed, then paused as Hui spoke again.
"Obito likes Rin. Maybe she could be the key to getting him serious."
Minato raised an eyebrow, then smiled mischievously.
"You're suggesting I use love to motivate him?"
Hui's silence spoke volumes.
Minato chuckled, his golden hair shining in the sun. Then, something occurred to him.
He had noticed how intently Hui watched Rin—not out of infatuation, but with analytical interest. It wasn't like how others admired her. Hui's gaze was clinical.
"Could it be… Hui sees her talent too?"
Minato's smile widened.
He was right.
Hui didn't care about fame or power. But Rin's potential in healing and sealing—disciplines Uchiha Kiyo had mastered—was immense.
"What do you think of Rin, Hui-kun?"
Hui turned to him.
"She has excellent chakra control and strong foundational talent. With the right guidance, she'll surpass expectations in both medical ninjutsu and sealing techniques."
Minato smiled.
"I was hoping you'd say that."
He patted Hui's shoulder.
"Would you consider mentoring her? I can teach her many things—but not what she needs for medical paths. Rin's talent is too good to waste. If she studies under someone like you, she'll shine."
Hui gave a small nod.
"It would be an honor."
Minato grinned, satisfied. For now, things were aligning perfectly.
Little did anyone know, the seeds of a new immortal path were already being sown in the heart of Konoha.