Naruto: I Can Upgrade My Techniques Infinitely

"Hiss…" At that exact moment, Kakashi was eating with Guy, when suddenly a searing sensation like fire burned through his arm. He instinctively sucked in a cold breath—only to realize his arm was completely fine.

"Kakashi, are you alright?" Guy asked curiously, craning his neck to look around, as if expecting an ambush.

"I'm fine. Just… remembered something unpleasant." Kakashi's face darkened.

For some reason, he suddenly recalled his previous spar with Nara Kazuki. That guy had developed a whole nasty combo for fighting opponents. He'd open with a Fire Style: Great Fireball Jutsu, then follow up immediately with Fire Style: Dragon Flame Jutsu. The double wave of heat left the opponent dazed—sometimes even puking, cramping, or having mysterious diarrhea. There was just no defending against it.

Kakashi had tried dozens of ways to counter it, but nothing worked.

It left him baffled and irritated. He suspected Kazuki had developed some kind of bizarre hybrid ninjutsu. Wouldn't be surprising—there were all kinds of strange new techniques these days. Some, like the First Hokage's Wood Style, still had no known effective counter even after decades.

He wondered how some unlucky bastard would feel running into Kazuki in the field. Kakashi himself had started dreading their spars. Whether he won or lost, it always felt like a miserable, humiliating struggle.

"Defensive jutsu up! This brat's Great Fireball has some kind of auditory genjutsu effect!" someone barked. A Doton: Earth Wall Jutsu sprang up to block Kazuki's oncoming fireball—only to be followed immediately by a second stream of intense flames.

Kazuki's brow rose. Whoever was casting these jutsu had serious strength.

Then the figure emerged—and everything clicked into place.

Kakuzu.

Of course.

Kakuzu was obsessed with money, and considering the huge sum they were transporting, it would've been weirder if he hadn't shown up to try and steal it.

Kazuki had faced him before—only as backup—but he respected Kakuzu's power. After all, the man had earned his spot in the Akatsuki and was valued by Pain himself.

There were plenty of rogue ninja affiliated with Akatsuki, but only a few were full-fledged core members—the real "Akatsuki elite." Others handled the grunt work.

When Pain picked members, the top requirement was raw combat ability. Some, like Orochimaru, were one thing—but Kakuzu and Hidan were different. Kakuzu had superior all-around power, while Hidan relied on his unique immortality and ritual-based curse techniques.

Kazuki had already taken out Hidan.

Which meant Kakuzu was probably operating alone for now—without a new partner. From the look of his hands—no Akatsuki nail polish yet—Kazuki figured he might not have officially joined them yet.

While Kazuki dealt with enemy grunts, Suzaku had already rushed forward to confront Kakuzu directly. Kazuki watched carefully, planning to assist once the small fry were handled.

Despite Kakuzu's formidable power and near-immortality, he wasn't as unpredictable as Hidan. Suzaku could handle him for a while.

Kazuki, however, had already been drawn into a clash with someone he didn't recognize—clearly no ordinary foot soldier. Which meant Kakuzu had brought a comrade of at least jōnin-level strength to help with the heist.

Kazuki opened his mouth and unleashed another Fire Style: Great Fireball Jutsu. His opponent clearly expected it and dodged expertly, even avoiding the creeping shadow that tried to grab him from below.

Kazuki frowned. The guy had intel—probably straight from Kakuzu. His usual techniques wouldn't land easily this time. No matter—Kazuki had plenty more.

He weaved hand seals as the enemy lunged at him with a downward slash. But Kazuki finished the seals first—faster—and exhaled a roaring Fire Style: Dragon Flame Jutsu.

The attacker's strike hit only a wooden clone. Kazuki himself had leapt into the treetops. His palm shimmered as he charged a Rasengan and launched himself down like a missile.

"I want to see what it's like to land a 100% Monkey Steals the Peach."

A sick little thrill danced in his mind. This would be the first time he'd used the upgraded Rasengan against an enemy for real. His fight with Minato had just been sparring—he'd held back.

"Persistent little bastard," the enemy muttered, suppressing the urge to vomit as he barely avoided the Dragon Flame assault.

Then he saw Kazuki rocketing toward him, glowing orb in hand. He didn't recognize the technique, but instinct screamed: don't let that touch you.

He used Body Flicker and a Substitution Technique, barely slipping away.

But before he could recover, Kazuki was already on him again—Rasengan glowing in his palm—aiming straight for the most forbidden of targets.

"No—!"

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