Naruto: I Can Upgrade My Techniques Infinitely

Nara Kazuki squatted atop a wooden post in the training field, deeply immersed in figuring out how to condense his Rasengan faster—and how to possibly modify it altogether.

Originally, Hiruzen Sarutobi had intended to teach Kazuki a jutsu after his sparring match with Kakashi. But after witnessing the power of Enma Form, Hiruzen had shelved the idea for now and told Kazuki to wait.

'Looks like my potential finally showed itself in front of the higher-ups...' Kazuki thought as the Rasengan spun wildly in his palm, the power straining to break free, hard to control.

His attempt at fusing Fire Release into it had failed too, so he smashed it into the ground out of frustration, leaving a twisted, smoking crater.

The Rasengan proficiency meter ticked up slightly.

"Training is hell. If only I could shortcut it with offerings… but even that's unreliable," Kazuki muttered, scratching his head.

He'd experimented with sacrifices before—offering up things to that presence—but most of the time it yielded nothing. Only once had he gotten a reward, and that was when he'd sacrificed Hidan to Nyarlathotep. That had netted him some valuable free proficiency points.

But regular shinobi? Worthless.

So Kazuki suspected that the key wasn't just in the act of sacrifice—but in the uniqueness of the offering. The more distinct and twisted the subject, the more likely it was to attract that being's gaze.

"Guess I should start taking missions involving cultists again… though among them, only Hidan's really got a name," Kazuki murmured, shaping another Rasengan as his shadow clone in the distance worked on refining Great Fireball Jutsu.

"Kazuki," a familiar voice called out.

Hiruzen Sarutobi approached, his gait steady and slow. Kazuki noticed the old man's eyes held even more approval than before.

If Hiruzen still took disciples, Kazuki was starting to believe he might've just been made the final one.

"I've reviewed that unique jutsu of yours. It's very interesting—and it clearly enhances your Fire Release techniques, doesn't it?" Hiruzen said with a pleasant smile.

Kazuki blinked. The old man's sharpness still surprised him. But he nodded.

"Come. Let me demonstrate something for you," Hiruzen said cheerfully. He began forming hand seals—not too quickly—deliberately letting Kazuki see each step. Kazuki watched intently, memorizing every movement.

"Fire Style: Great Fire Annihilation!"

A sweeping wave of fire erupted from Hiruzen's mouth, fierce and massive, roaring toward the sky like it could scorch the heavens themselves.

Kazuki blinked in stunned silence.

Damn. Was Hiruzen secretly Uchiha Madara or something?

Great Fire Annihilation? That was supposed to be one of Madara's signature jutsu.

But then again… this was the Third Hokage, the so-called "Professor" of ninjutsu. Maybe it wasn't so surprising after all.

"This jutsu is called Great Fire Annihilation. Originally developed by the Uchiha clan, its range and power scale with the amount of chakra used. It's incredibly destructive. However, due to the chakra cost, it's not suitable for frequent use unless you have a vast reserve or special conditions," Hiruzen said, coughing lightly after finishing.

Kazuki nodded and mentally jotted everything down. The technique looked like a chakra hog, but it might have other uses—especially once he built up his reserves.

Eventually, after enough kills, he'd become a walking chakra generator anyway. At that point, cost wouldn't matter.

Hiruzen looked at Kazuki with visible satisfaction. Smart, talented, possibly with a unique Kekkei Genkai—the kind of ninja that gave him hope for Konoha's future. This was the kind of spark that needed to be passed on to keep the Will of Fire burning.

He left shortly after, his mood visibly good. Kazuki could guess why. Watching his back retreat, Kazuki felt the old Hokage had left a positive impression—nothing like the scheming, heartless versions some rumors painted.

Kazuki felt pretty upbeat himself. He decided to look for Kakashi, maybe talk lightning-style ninjutsu, share notes.

But as soon as he entered the village streets, he spotted Danzo Shimura.

The old vulture was walking with two other shinobi down the street, and Kazuki instinctively took a detour.

Danzo was a pain in the ass. If he crossed paths with him now, he might get "volunteered" for some Rain Village reconnaissance mission.

And that was exactly the kind of insane assignment Danzo would issue without blinking.

Just as he turned into a side alley, a mocking voice reached his ears.

"You lot haven't paid your neighborhood maintenance fee this month…"

Kazuki peeked over.

A Konoha Police officer, clearly an Uchiha, stood arrogantly at a doorway, acting sleazy toward someone inside.

Kazuki's eye twitched.

Really? This cliché?

Was today the day he'd get to pull off a classic "hero saves the damsel" scenario?

He couldn't hear what was said inside the house, but the Uchiha's grin grew more lecherous by the second. The moment reeked of that overused, sleazy drama setup.

Hero intervenes, saves the girl, if he's handsome she falls for him, if not… well, she'll thank him in the next life.

"What? You don't have money? That's fine… we can work something else out~" The Uchiha licked his lips, face twisted into a perverted grin.

Kazuki stepped forward. Time to bring some justice—maybe throw in a good beating while he was at it. Bastards like this helped ruin the Uchiha's rep in the village.

He was just about to swing when—

The Uchiha reached out…

And slapped his hand on the chest of a hulking man standing inside the door.

Said man's expression was as black as soot.

Kazuki froze mid-step.

"…Huh?"