Naruto: I Can Upgrade My Techniques Infinitely

"What the hell is that?!" The Iwagakure shinobi stared in shock at the sight before them. They had already rushed out to intercept, but what stunned them most was the monster standing in their path.

Several of them hesitated mid-hand seal. That one second's delay was enough to spell death.

Yakushi Kabuto's pupils dilated as he gazed, stunned, at Nara Kazuki.

"What... is that..." Kabuto murmured, mind reeling.

He considered himself experienced—he'd played spy more times than he could count. And as long as it meant keeping Nonō Yakushi—the kind woman who raised him—alive, Kabuto was willing to do anything.

But even he had never seen a jutsu like this.

Just moments earlier, a blinding bolt of lightning had struck the Konoha shinobi sent to retrieve him. The light was so intense that Kabuto had instinctively shut his eyes.

And when he reopened them, what stood before him was a blazing figure wreathed in fire, arcs of lightning crawling across its body like serpents.

"Move," Kazuki snapped, frowning at Kabuto. Damn it, he could understand villagers freezing up—but a trained spy?

Whether Kabuto had turned traitor didn't concern Kazuki. He knew the future—Kabuto still had years of getting jerked around by Shimura Danzō.

"Damn it, Danzō really is the workhorse of the ninja world... where there's a mess, there's always him." Kazuki muttered, shaking his head. Danzō had become the go-to scapegoat for everything. Kazuki was beginning to suspect Kishimoto had written him specifically for that purpose.

Kabuto snapped out of it and retreated quickly. Kazuki raised his hand and flashed a signal—meant for Shisui and Itachi.

There were at least ten enemy shinobi ahead, and their precise strength was unknown. Worse, they weren't far from Iwagakure itself. A prolonged fight here would turn suicidal fast.

Shisui and Itachi's job was simple: escort Kabuto out.

Kazuki would hold the line.

His own safety? Not an issue. He had already sent a Shadow Clone far off as an emergency switch-out.

"What the hell is that monster?!" several Iwa ninja cursed, attempting to intercept Kabuto. But Kazuki didn't give them the chance.

The moment he activated Lightning Release: Flame Demon Aspect, he understood what he had unleashed. It wasn't just a jutsu—it was an overwhelming augmentation.

[Lightning Release: Flame Demon Aspect — consumes massive chakra to generate explosive combat power. Induces unresistable burning pain, though no physical damage. During this state: Fire Release jutsu gain drastically increased casting speed, power, and area of effect. User gains resistance to Fire and Lightning Release jutsu. Strikes against enemies build Rage. Upon reaching max Rage, chakra can be spent to enter an enhanced phase, dramatically increasing all attributes.]

Kazuki grinned when he saw the description—absurdly powerful.

Except for one catch: the unresistable pain.

It was like having your skin seared by a lighter constantly. No way to block it. The pain was maddening.

"Fuck that hurts!" Kazuki growled, but his hands were already forming seals.

He completed the final seal and unleashed a massive Great Fire Dragon Technique—not one, but twin fire dragons roared forward from his arms.

"Earth Release!" The Iwa shinobi screamed, their eyes bloodshot as they summoned defensive walls. The sheer size of the incoming flames caused panic, and even the most hardened among them faltered.

Some couldn't even form seals properly. One shinobi's sphincter clenched so hard in terror that it delayed his seal movements.

Because, as everyone knows, when diarrhea hits, even the toughest man crumbles.

Kazuki didn't let up.

He spread his arms wide and formed another set of seals. Twin Great Thunder Fireballs surged forth, one from each palm, blasting toward the Iwa shinobi trying to flank Kabuto.

"Still trying?" Kazuki muttered, his voice low and guttural. Then, incomprehensible words spilled from his mouth—arcane, alien syllables that made every shinobi within earshot blank out in confusion.

"Snap out of it!" One Iwa shinobi managed to react, but by then the fireballs were already in his face. He had no time for anything but the fastest defensive technique he knew.

BOOM! A mushroom cloud erupted.

Kazuki felt the Rage Meter surge within him, the pain and anger fueling each other in a vicious loop. The fire licking across his skin, the thunder in his blood—it made him want to burn them all.

But Iwagakure shinobi were no rookies. They regrouped fast. Even as the fire still blazed, stone spears lanced through the flames, and two arms emerged from the ground, grabbing Kazuki's legs.

Kazuki glanced down. His hands moved fast.

He formed the Tiger seal and unleashed a Fireball Jutsu straight at his own feet.

Because in this state, Kazuki could cast Fire Release jutsu from any part of his body.

He could, technically, shoot a fire dragon from his waist if he wanted. Not that it'd help.

The explosion at his feet shattered the ground, launching him skyward. As he ascended, stone spears lunged toward him—but Kazuki kicked off one mid-air and used it to vault even higher.

"Earth Release!" another shout echoed.

Above him, a massive earth wall formed and began to crash down, aiming to crush him mid-air.

Hands burst from the ground again, grabbing at him as the stone wall descended.

BOOM!

The rockfall kicked up a thick curtain of dust and debris.

"Hurry! Catch that Konoha spy!" the lead Jōnin ordered, face pale. He'd nearly vomited from the pain of being hit by the Great Thunder Fireball—the fire scorched his skin, and the lightning left his nerves singing. He didn't puke—but only because it got roasted back down his throat.

And that made him furious.

"You... where do you think you're going?!"

The voice came from beneath the shattered stone wall.

Three Iwa shinobi froze. Then—

"Earth Release!"

Dozens of stone spikes burst from the ground, piercing through the rubble.

And from that rising cloud of flame and smoke...

A monster cloaked in fire clawed its way out.