Sasuke's Training

After returning home and eating her fill, Karin unexpectedly took the initiative to ask to study in the basement. That made Aoba's heart stir.

The two then headed to the basement. Aoba had isolated this place with all kinds of Sealing Jutsu. Neither the Telescope Technique nor White Zetsu's spying could possibly see inside.

"Aoba, I noticed something very strange. One of those monsters you mentioned has been lingering near our house lately."

"Near us?"

Aoba's heart shifted slightly. He realized he had overlooked a problem. Before, he had not been worried about White Zetsu spying on him, because he had merely been an insignificant nobody. The active White Zetsu were limited at this stage, so they could not possibly waste their energy on him.

But after he had "defeated" the Raikage, the Wind-Chasing Sword had become one of the biggest names in the Shinobi World. Naturally, that could attract White Zetsu's attention.

Fortunately, Aoba's important experiments were all conducted in the isolated laboratory. White Zetsu could not detect them. Otherwise, who knew how many complications might have arisen.

"Where is it now?"

"I can't see it right now. But when I came back earlier, it was right beneath our house, only a dozen meters away."

Aoba understood at once. White Zetsu had probably noticed his secret laboratory. It would definitely be curious about a place blocked by Sealing Jutsu that it could not see through. That was why it had drawn so close to the surface. It wanted to find out what this suddenly famous ninja was secretly working on.

"Good, Karin. Remember, don't pay too much attention to it. Other than confirming its location, do not watch that thing too closely. And when it gets directly beneath our floorboards, tell me."

"Understood." Karin was a little excited. Children were always interested in playing ninja. Before graduating, they always imagined becoming great ninja and roaming freely across the battlefield. But in truth, no ninja who had gone to war failed to miss their days at the academy.

Playing ninja had never been a children's game. It was a deadly game woven from iron and blood.

After the New Year, during the last few days of the holiday, Aoba remembered that he still had an agreement to fulfill.

By the river outside the village, Sasuke Uchiha had already been waiting so long that he was growing impatient. He had even started wondering whether Aoba had tricked him.

Before the New Year, he had met Aoba. Aoba had made a very strange request of him: during the holiday season, he was to hold a banquet at the Uchiha residence and invite the classmates he got along with.

Sasuke had never seen such an absurd request in his life. He had even suspected that the other man was deliberately making things difficult for him, because all of Konoha knew that he was unsociable. Yet that guy had insisted on making him do something like this.

But the technique that could kill Itachi Uchiha was simply too tempting. Sasuke might have been proud, but after sparring with Aoba several times, he had clearly realized that he was still far, far too weak.

At this rate, he would never be able to kill Itachi Uchiha. Driven by his thirst for revenge, along with another emotion he could neither name nor understand, he had ultimately held that gathering at the Uchiha residence before the New Year.

Though Sasuke had spent the entire event feeling like he was sitting on pins and needles, awkward to the point of death, looking back on it afterward, it had surprisingly felt pretty good.

And after that, his relationships with those classmates seemed to have grown much closer. During the New Year, quite a few people had even brought holiday gifts to his home. In short, after the Uchiha Clan had disappeared, Sasuke's New Year had turned out unexpectedly well.

He had also discovered a rather "terrifying" fact.

He did not seem to dislike the feeling of those gatherings.

He shook his head, throwing away those messy thoughts. What am I thinking? I'm the last Uchiha, a man burdened by a blood-deep vendetta. How could I immerse myself in childish fooling around like this?

"What are you thinking about, Sasuke?" a voice suddenly asked from behind him.

"The date of the next gathering." Sasuke regretted it the moment he said it. He spun around and found Aoba standing behind him, smiling at him.

"Oh? Looks like the last gathering worked out well. Keep it up."

"Enough. I've fulfilled your request. Now it's time for you to keep your promise." Sasuke tried his best to look cool and aloof, but in Aoba's eyes, that was just another child's little game.

"All right. I won't go back on something I promised you. I came today to fulfill it. If I remember correctly, you have both Lightning and Fire natures, right?"

"That's right."

"Good. The technique I'm teaching you is a Lightning Release ninjutsu."

"Lightning Release?" A trace of confusion flashed through Sasuke's eyes. According to the information he had, Aoba was a Wind Release ninja who specialized in Wind-style Nintaijutsu.

"Heh, we're ninja, Sasuke. Remember this: always leave yourself a trump card. A card that can turn things around when your life is on the line. That is what a true ninja does."

"A trump card... I understand."

"Good. Now, let's begin properly. Before you learn this technique, there is one prerequisite. You need to master Lightning Release Nature Transformation."

"Nature Transformation?" The Ninja Academy of Konoha would never teach such advanced knowledge. In truth, it was somewhat early for Sasuke to be learning this at his age.

If it had been anyone else, Aoba would not have taught them this way. But Sasuke did not matter. As Indra's reincarnation, he was one of the two biggest cheaters in this world. Squeezing a little more out of him was no big deal.

Sasuke had always believed himself to be a genius. At the Ninja Academy, he had ranked first in every practical combat class. To him, all of that had been simple and easy to understand.

But after he began learning Aoba's ninjutsu, he experienced true difficulty for the first time. Difficulty beyond imagination. For three straight days, he trained desperately, yet he had not even managed to complete the so-called Nature Transformation.

In other words, he was not even qualified to learn that technique yet. That left Sasuke somewhat discouraged, but also a little relieved. In his eyes, the harder the technique was, the greater his chance of defeating Itachi Uchiha. Now, he believed that Aoba had not deceived him.

In reality, Sasuke Uchiha's progress was already astonishing in Aoba's eyes. Releasing ordinary ninjutsu required gathering chakra and then forming hand seals.

The process of forming seals was essentially the process of transforming chakra into ninjutsu.

But Aoba's ninjutsu required no seals. In fact, every ninjutsu Aoba had developed himself was seal-less. That was because developing hand seals was extremely dangerous. Even if you could understand the effect of every single seal, once they were combined, they might not produce the result you wanted. They could even cause a backlash.

That was why developing ninjutsu with hand seals was so dangerous. At this point, one had to mention the Second Hokage, Tobirama Senju. That guy had produced forbidden techniques one after another, yet somehow had not died in the process. Aoba truly found that hard to understand.

But Aoba himself would not take such a risk. Apart from already established ninjutsu, anything he developed himself would use no seals whenever possible. In fact, Aoba's limit was one seal.

In other words, the ninjutsu he developed himself would use no more than a single hand seal.

What he was teaching Sasuke now was precisely his trump card: Lightning Release: One Flash. It was the Shinobi World version of the Super Railgun.

The principle behind this technique was to use lightning to create an electromagnetic acceleration track, then fire an iron ball through it. As everyone knew, electromagnetic acceleration consumed an enormous amount of energy. Therefore, this technique also consumed an enormous amount of chakra.

Most importantly, Aoba had discovered that there was simply no way to use the hand seals of the Naruto world to complete both electromagnetic conversion and acceleration. Even if there was a way, he felt it would require at least twenty hand seals.

A ninjutsu that complex was complete nonsense in actual combat.

So Aoba used a clumsier but much simpler method. He relied on his exceptionally strong chakra control to forcibly complete the entire sequence in his hand, then directly launch the metal ball.

Without hand seals, he had to complete Lightning Release chakra transformation, electromagnetic conversion, and the launching process all at once. It was not merely a matter of whether it was difficult or not. It was fucking hard.

Even Aoba, whose Mental Power was abnormally powerful and whose chakra control was practically cheating, had spent several months just barely completing the process.

It took another year before it could be used in actual combat.

And even then, Aoba still felt it was not fast enough. Only when he could use this move as effortlessly as the Railgun girl could it be considered truly mastered. Moreover, this move consumed a tremendous amount of chakra. He could not use it many times at all. For now, it could only remain a hidden trump card.

While Sasuke trained, Aoba trained as well. He was practicing the Rasengan. He was not afraid of the Third Hokage seeing it; he was even deliberately showing it to him.

The Rasengan was an S-rank ninjutsu. Not because the technique itself was especially difficult. In truth, its principle was very simple, countless times simpler than Aoba's One Flash.

What made it difficult was chakra control. By that measure, Aoba's One Flash was probably more than twice as difficult as the Rasengan.

That was because the original Rasengan had no chakra Nature Transformation. It was merely a highly compressed sphere of chakra. Meanwhile, even getting started with Aoba's One Flash required chakra Nature Transformation. Its difficulty was truly absurd.

But once it was unleashed, its power was equally unimaginable. An iron ball accelerated to Mach 10 or even faster in an extremely short time possessed piercing power beyond description.

Aoba had developed this move to deal with the Uchiha Clan's Susanoo. That thing was practically absolute defense. Once activated, ordinary ninjutsu could not even scratch it.

But Susanoo was enormous and relatively slow-moving, making it the perfect target for a Railgun. From that perspective, the move was also extremely suitable for dealing with Itachi Uchiha. The only prerequisite was getting Itachi Uchiha to use Susanoo.

Of course, the same applied when dealing with Tailed Beasts. Tailed Beasts were huge and basically incapable of dodging such a high-speed ninjutsu. The results should be good as well.

In fact, this technique had another use: sniping.

There were many long-range ninjutsu in the Shinobi World, but Aoba had not found any meant for ultra-long-range sniping. Minato Namikaze's techniques had been somewhat similar back then, but he essentially flew over himself to ambush people.

Aoba's Railgun could strike targets from several kilometers away. But that created an awkward problem.

Ultra-long-range sniping required visual assistance. Otherwise, it would not be accurate. And Aoba could not manage that.

This world had telescopes, but telescopes and scopes were completely different things. Besides, Aoba used his own arm to perform this move. Even a scope would not help.

This problem was easy to solve in the Shinobi World. The Byakugan was one of the most perfect solutions. Just imagine it: a Byakugan ninja spotted an enemy from several kilometers away.

Yet he did not move from where he stood. He simply fired an ultra-long-range Railgun and blew off the head of an enemy hiding inside a tree hollow. What an incredible scene that would be.

But in reality, Aoba did not have the Byakugan. And the Hyuga were extremely closed-off. Aoba had no connection to them, so if he suddenly showed up and said he wanted to take a Hyuga clansman as his disciple, they would never agree.

And from another angle, Lightning Release: One Flash was an extremely dangerous ninjutsu. If it fell into the hands of someone with bad intentions, Aoba would not sleep soundly at night. He could not possibly teach it to people casually.

Sasuke was one of this world's chosen ones, so Aoba could make an exception. As for anyone else who wanted to learn it, Aoba would not teach them so easily.

"All right, Sasuke. That's enough training for today."

"But, Teacher Aoba, I can still..." Sasuke wanted to continue training, but Aoba interrupted him.

"Sasuke, have you forgotten what I said? Haste makes waste. This isn't a technique that can be completed through hard work alone. During training, you need to constantly identify your shortcomings and adjust yourself.

Carefully feel every tiny change in your chakra. When your body is exhausted, you cannot do any of that. So listen to me now. Go home and rest. We'll continue tomorrow."

"All right." Sasuke was a little disappointed, but his mood was still fine for now. As long as Itachi Uchiha did not come along every so often to provoke him, he was actually a good kid.

In the original story, both Itachi Uchiha and Sasuke had been far too obsessed with the Sharingan. Itachi Uchiha would even drag Sasuke into the Tsukuyomi space from time to time and make him watch the Clan Massacre Night for three days and nights. It was honestly ridiculous.

In Aoba's opinion, awakening the Sharingan too early was not a good thing. It certainly made one stronger, but it also proved that the Uchiha's emotions had become more extreme, and it placed an enormous burden on the body.

Aoba even felt that Itachi Uchiha's poor health was related to awakening the Mangekyō too early.

Without the Eternal Mangekyo Sharingan or Hashirama's cells, the Mangekyō's side effects were simply too severe.