Naruto: Getting Observation Haki By Sacrificing The Byakugan

"But if there are other enemies, we'll still have to rely on you."

"Don't worry," Kawaki Aoba replied calmly. "I already have a rough plan to protect the village. Follow me."

With that, Kawaki Aoba led Tobirama Senju, Qingke, and the rest of the group to meet with Minato Namikaze. After all, as the Fourth Hokage, Minato's approval was necessary for what came next.

"Aoba," Minato said, surprised, "you want to set up another layer of defense around the village?"

Kawaki Aoba nodded. "That's right. I've already refined the current barrier. With your authorization, I can deploy the new formation immediately. If all goes well, even most S-rank jutsu won't be able to break through."

Minato was momentarily speechless. "Ordinary S-rank jutsu... won't break it? That's not just good—that's phenomenal. And you're saying this will cover the entire village?"

It was a level of defense Minato had never imagined, much less seen. Still, he understood the urgency. With the threat of powerful enemies like Uchiha Madara and Nagato looming, there was no time for hesitation.

Seeing no reason to refuse, Minato gave his approval.

Without delay, Kawaki Aoba led a team to install twelve massive pillars—each two meters wide and nearly ten meters long—at strategic points surrounding Konoha. These weren't just any structures. They were sophisticated creations, a product of Divine Machinery Refinement—an intricate chakra-based engineering technique developed by Aoba himself after countless hours of research.

Each of the twelve pillars served as a foundation point for the barrier. Once activated, the system could tolerate damage to up to nine of the twelve pillars and still function, as long as three remained operational.

As Aoba activated the system, beams of chakra light shot skyward from each pillar, forming a lattice across the sky and linking together to create a dome-like barrier over the entire village.

Naturally, such a massive display attracted attention. Shinobi across the village looked up in awe as the barrier solidified. Even civilians, unaware of its mechanics, swelled with pride.

"This is Konoha," they whispered. "No other village can do this."

But among the sensory ninjas and the elite, the awe turned to disbelief. The chakra flowing from the pillars was overwhelming.

Tobirama Senju—brought back temporarily via Edo Tensei for consultation purposes—stood near one of the pillars, stunned. "This amount of chakra..." he muttered, unable to finish his thought. The sheer chakra pouring from a single pillar was staggering.

"How long can the barrier remain active at full power?" Tobirama finally asked.

"If left alone, without constant chakra replenishment, it'll last twelve hours under normal conditions," Aoba explained. "If it comes under constant assault, particularly from large-scale ninjutsu, that number may drop. Still, it was designed specifically to counter high-impact threats like Nagato's Chou Shinra Tensei."

Aoba had witnessed that technique firsthand during a mission in the Rain Country. Based on his calculations, this barrier could endure up to nine full-force gravitational blasts before collapsing.

Though dissatisfied with the system's limitations, Aoba knew it was the best that could currently be achieved. The onlookers, however, were overwhelmed just by the chakra required to sustain it.

Tobirama, in particular, was shaken.

Twelve hours... That means each pillar contains enough chakra to operate for at least an hour... he thought, his mind racing.

Each one equals the chakra reserves of my elder brother...

One pillar contained as much chakra as Hashirama Senju. That comparison left him speechless.

"How are you going to replenish that much chakra?" Tobirama asked at last.

"There's no need to worry about that," Aoba answered. "I made it, so I'll maintain it. I'll handle all the chakra replenishment personally."

Everyone froze.

Even among the powerful shinobi present, no one could comprehend how a single person could fuel such a massive system. Yet Aoba's tone left no room for doubt.

With Madara's return a looming possibility, the decision was made to keep the barrier active indefinitely. And while it was clear that no one else in the village could manage its maintenance, everyone understood one thing:

This barrier belonged to Kawaki Aoba alone.

The chakra requirement was simply beyond anyone else's capabilities.

Tobirama glanced at Aoba again. Despite his shock, he felt something else too—envy. Once, he had looked up to his brother's overwhelming chakra. Now, he found himself envying someone else entirely.

Compared to his former self, this version of Tobirama Senju—now residing in an Uchiha's body—possessed significantly less chakra. Take, for example, the large-scale Water Release techniques he once excelled at. Though still capable of performing them, he no longer dared to waste chakra as freely as before.

After all, the Uchiha clan's chakra reserves could not match those of the Senju. He chuckled inwardly—now he too was technically an Uchiha.

Tobirama unconsciously brushed his fingers across his eyes, where a new power was taking shape—a power he once despised more than any other.

As a leading expert on Uchiha physiology and dojutsu, how could Tobirama ever forget the Mangekyō Sharingan?

Even though he had always harbored disdain for Madara Uchiha, it would be dishonest to claim he never coveted the man's power.

Ever since becoming an Uchiha himself, Tobirama had gradually begun shedding his prejudice. His research into the Sharingan naturally became deeper and more personal.

The Mangekyō Sharingan, in his analysis, was nothing more than the pinnacle expression of Yin Release. The emotional trauma traditionally required to awaken it was, in his view, a crude trigger—a shortcut rather than a necessity.

But Tobirama Senju relied on intellect, not trauma. If the Mangekyō Sharingan was merely the peak of Yin Release, then to him, it was only a matter of scientific understanding.

Still, even with a powerful defensive barrier, they couldn't afford to lower their guard against Madara Uchiha. As a contingency, Minato formed a team of elite shinobi to intercept any potential reinforcements Madara might send.

These included clan leaders and high-ranking shinobi: Tobirama Senju, Asuma Sarutobi, Aoba Yamashiro, among others.

They were a failsafe—hopefully unnecessary, but crucial nonetheless.

As for Madara himself, few dared speak his name. That god-like power could only be entrusted to Aoba Kawaki.

Even Minato Namikaze admitted he could only support Aoba using Sage Mode and the Flying Thunder God Technique.

Once all preparations were finalized, Tobirama voiced the question that had been on everyone's minds.

"Aoba-sama, this barrier consumes a tremendous amount of chakra. Its defense must be incredible. May we test it?"

Aoba Kawaki nodded. "Of course. We don't even need to go outside—the barrier works identically from within. Feel free to try it. Think of this as a preemptive test. I'll replenish the chakra afterward."

At the mention of chakra, silence fell. How could Aoba speak so casually of such consumption, as if it were a trivial matter?

Was this the terrifying reality of a chakra powerhouse—utterly beyond comparison?

With Aoba's approval, the shinobi began testing the barrier with their signature techniques.

Tobirama went first. Of everyone present, he was the most curious about the barrier's mechanics.

Water Release: Water Dragon Bullet Technique!

A sequence of four rapid hand seals—completed in less than four seconds—and a massive water dragon surged forward, captivating onlookers with its sheer scale.

Even more astounding was the fact that the technique came from someone now technically an Uchiha. The irony was not lost on anyone.

The dragon crashed into the barrier with immense force… yet not even the faintest ripple appeared.

The defense was nothing short of astonishing.

Tobirama, however, remained unsurprised. With such vast chakra consumption, anything less would have been disappointing.

His Water Dragon Bullet had served to test the barrier's response to kinetic impact. The results spoke for themselves.

Had he not wanted to be too conspicuous, Tobirama would have followed up with his Hard Vortex Water Blade, his true signature jutsu. But with Minato present, his Rasengan would serve as a similar comparative gauge.

Indeed, Minato stepped forward, forming the Rasengan in his palm. The result was no different—no reaction from the barrier.

Other shinobi followed with their clan techniques and elemental jutsu—Fire, Wind, Earth—but all proved futile against the barrier.

Just as Tobirama assumed the test was over, he felt a familiar chakra fluctuation.

Turning, he saw Minato beginning to gather Sage Chakra.

Sage Mode.

Although his entry was slower and his mastery not on par with Hashirama's, the presence of natural energy was unmistakable.

Red pigmentation formed around Minato's eyes, and his presence sharpened dramatically.

Where once he had been a swift assassin with limited attack power, now he radiated a more dangerous, balanced threat.

Sage Art: Super Big Ball Rasengan.

With Sage Chakra enhancing it, the Rasengan grew in size and force, slamming into the barrier.

Still, the result seemed the same—no visible damage.

But Aoba Kawaki noticed something others didn't.

The chakra expenditure required to maintain the barrier had suddenly spiked.

It wasn't just the attack's brute force—it was the Sage Chakra itself.

Aoba considered the implications. He was now 90% certain: Sage Chakra had a unique interaction with the barrier's structure, bypassing some of its absorption properties.

Even so, it didn't matter.

Aoba would personally confront Madara Uchiha. The others would handle Nagato and Obito.

Obito had no connection to Sage Mode, and Nagato likely hadn't developed his Rinnegan to absorb and wield Sage Chakra efficiently.

And even if he had, the barrier could probably withstand even the combined Sage-powered assaults of the two.

---

Amegakure, Hidden Rain Village.

Within the shadows, Black Zetsu reported the developments in Konoha to Madara Uchiha.

Upon hearing of the new defensive barrier, Madara raised an eyebrow, interest flashing in his eyes.

"A barrier, huh? Another one of Aoba Kawaki's creations? Intriguing."

His lips curled into a smile.

Between the mysterious power behind Aoba's eyes—comparable to the Rinnegan—and the man's growing reputation, Madara found his curiosity increasingly piqued.

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