Naruto: Kakashi, the Ultimate Shinobi

The Anbu, officially known as the Ansatsu Senjutsu Tokushu Butai (Assassination and Tactical Special Unit), was formed during the reign of the Second Hokage, Senju Tobirama. Its core responsibilities include protecting the Hokage, conducting covert operations, and neutralizing foreign threats. Members don white animal-themed masks to preserve anonymity while on missions.

Life as an Anbu operative is monotonous, soaked in bloodshed and secrecy. Entry into this elite force demands exceptional skill, specialized equipment, and, more importantly, the Hokage's trust.

Naturally, the Anbu isn't monolithic. There are two principal divisions: the Hokage's direct Anbu and the Root division, established by Shimura Danzo.

These factions are ideologically distinct and operationally separate, rarely collaborating and often at odds. The tension between Danzo and the Third Hokage, Hiruzen Sarutobi, has long been an open secret among Konoha's leadership.

The Anbu Headquarters is the central gathering site for those directly under the Hokage's command.

Though Kakashi Hatake hadn't visited this place since his resurrection into the timeline, his previous self had walked these halls frequently. During the Nine Tails' attack, many of Kakashi's original Anbu teammates perished. In response, the Third Hokage assigned him new partners.

Kakashi was already acquainted with these three—after all, they had once worked under Minato Namikaze, his beloved mentor. Being Minato's student, Kakashi was naturally familiar with them.

When he entered Anbu HQ, his new teammates were already there—though still unmasked, making recognition effortless.

As Kakashi stepped inside, all three turned to him at once.

"Oh, Kakashi. You're finally here—we've been waiting quite a while," said Shiranui Genma, a senbon tucked casually in his mouth as he raised a hand in greeting.

"Sorry, I just got the summons," Kakashi replied, his tone apologetic. Whatever the reason, making others wait—especially comrades—was impolite. A sincere apology was due.

"Well, no harm done. Let's get briefed and head out," Genma said calmly.

"Right. What's the mission?" Kakashi asked.

"Nothing complicated. Just routine reconnaissance. We're to assess the border between the Land of Fire and the Land of Lightning, and retrieve the latest intel from the stationed patrol."

Among the trio, Genma was the eldest and most composed. It fell to him to relay mission objectives.

"I see. When do we depart?" asked Kakashi.

"No need to rush. We've got an hour to prep. Rendezvous at the village gate in sixty minutes. Clear?"

"Understood."

"Alright then, dismissed!"

With Genma's signal, the group dispersed.

Kakashi returned home to gather supplies, sealing them efficiently into scrolls. As he organized his gear, his gaze fell upon a peculiar kunai—one marked with a special seal on its handle, a kunai from Minato.

He paused, fingertips brushing over the markings. "Sensei…"

This was no ordinary blade. Etched with the Hiraishin no Jutsu—the Flying Thunder God Technique—it carried the symbol of inevitable death for those targeted. The moment this kunai was placed, Minato could teleport to it instantly.

Unlike Kamui, which distorted space via the Mangekyō Sharingan, the Flying Thunder God was a pure space-time ninjutsu, elegant and terrifying. Its simple seal belied the profound theory it embodied.

Minato, never one to hoard knowledge, had even passed the technique to his personal guard platoon. He had intended to teach Kakashi too, but fate interfered. Darkness consumed Kakashi's path after the loss of his teammates, and the right time never came.

Regret lingered—an unrivaled technique, now orphaned.

Even Genma and the others, who had trained under Minato, could only execute a synchronized variation. It wasn't the genuine Flying Thunder God.

Perhaps only Tobirama Senju, reincarnated via Edo Tensei, and Minato himself could revive its full glory.

Lost in thought, Kakashi gently traced the seal again.

"Hm?"

A sudden shift caught his attention. The kunai should've been cool—but it was faintly warm.

Looking closer, he realized it wasn't the metal but the seal that radiated heat.

Black ink shimmered faintly, chakra subtly pulsing from within.

Minato's chakra?

Kakashi's eyes widened. Minato was long gone. How could his chakra still flow within this relic?

But then again, it made sense. The Flying Thunder God required a chakra signature to bind location. Perhaps this residual energy was intentional.

"Incredible… Even in death, Sensei's chakra lingers. It explains how he used his stored seals after being reincarnated by Orochimaru."

Kakashi's curiosity surged. He had to understand. This wasn't just a tool—it was a key to a forbidden door.

To decipher its secrets, he would need enhanced vision.

Without hesitation, he lifted his forehead protector.

Sharingan—released.

The scarlet eye gleamed, three tomoe spinning rapidly. He focused, pouring his chakra into the dojutsu, trying to unravel the space-time matrix encoded in the seal.

"…Not enough. The standard Sharingan can't penetrate this level of complexity…"

Then—

Mangekyō—activate!

The tomoe twisted inward, forming a shuriken-like design.

His vision sharpened instantly, but the cost was high. Chakra surged from his core, consumed at a frightening rate.

"Amazing… So many layers hidden in such a compact seal."

Even now, he could only grasp a fraction—yet it was mind-bogglingly intricate.

No wonder none after Minato had mastered this art. It wasn't just knowledge. It was instinct, talent, battle-readiness, and unrelenting clarity.

While Kakashi marveled, his Mangekyō flared.

Suddenly, intense heat surged through his eye—his Mangekyō began to spin wildly!

The kunai seal responded. The black markings trembled, peeled from the blade, and—

were pulled directly into Kakashi's left eye!

"What the—?!"

Kakashi staggered, stunned. What just happened?

The seal—Minato's mark—had fused with his eye.

Panic mixed with awe. What did this mean?

What power had he just absorbed?

And why… now?