Naruto: Kakashi, the Ultimate Shinobi

Closing his left eye, Kakashi felt an unfamiliar shift within his transplanted Sharingan.

Something stirred within the original Uchiha ocular power—something beyond what he knew. What had just occurred while using the Flying Thunder God's marker kunai?

The Mangekyō Sharingan had reacted—no, absorbed the technique.

What the hell was happening?

Kakashi struggled to make sense of it. After all, the Flying Thunder God Technique had never been linked to the Mangekyō Sharingan. It was Minato's unique space-time jutsu, one of a kind. But wait… perhaps they weren't unrelated after all.

This Mangekyō was Obito's. Obito's own abilities had been rooted in space-time manipulation. Kamui. And Flying Thunder God was also a space-time ninjutsu.

Could it be—was there some kind of resonance?

Kakashi didn't have an answer yet. The connection was vague, but possible. Apart from sharing the same spatial properties, the two techniques had nothing overtly in common. Still, something had definitely happened.

He resealed the Mangekyō and took a deep breath. Despite the confusion, he was elated—the principles of the Flying Thunder God were now flowing through his mind, obscure but decipherable.

This was the essence of Minato's divine technique.

Suppressing his excitement, Kakashi steadied his thoughts. He hadn't expected that a single kunai marked by Minato would grant him insight into such an advanced jutsu. It was sheer fortune—maybe even fate.

But reality came crashing back quickly.

These techniques… were immensely complex.

Even with his intellect and mastery over jutsu, Kakashi estimated it would take at least two to three years just to fully comprehend the theory. To master it in combat? Perhaps five years. Maybe more.

Most critically, the technique demanded lightning-fast reflexes. While Kakashi's reaction speed was elite, it still didn't compare to Minato's. To wield the Flying Thunder God effectively, he would need to match the Yellow Flash in response time.

No shortcuts. No compromises.

Still, even if it took him six years, it would be worth it.

"Five or six years… that's not unacceptable." Kakashi clenched his fist, eyes gleaming. He hadn't imagined he'd inherit such a legacy so soon.

Gazing at the marked kunai in his hand, he murmured, "Minato-sensei… was this your parting gift?"

He gently placed the kunai back into his pouch. This weapon, though simple in form, held the essence of a Hokage's legacy. Kakashi would never discard it—never.

With his thoughts reorganized, Kakashi finally left his home and headed toward Konoha's main gate.

His mission would take considerable time—he was heading to the Fire Country's border, far from the Hidden Leaf. Even traveling at top speed, it would take at least five days to reach the rendezvous point.

As he neared the gate, the towering wooden doors loomed ahead. His three teammates were already waiting.

"Kakashi, you're so slow," Genma Shiranui complained as he leaned against a post.

Technically, Kakashi wasn't late—there was still a full minute left before the scheduled hour. Genma had simply arrived thirty minutes early and was itching to go.

Kakashi might've made it even sooner if it weren't for the Flying Thunder God incident. Still, he responded calmly, "My apologies. I'll be more punctual next time."

Genma opened his mouth again, but Raidō Namiashi interjected, "It's fine. We were just early."

That shut Genma up quickly. He had no real grounds to argue.

Ibiki Morino stood silently at the side, saying nothing as usual. His quiet presence always gave off an intimidating aura, even at a young age.

Kakashi wasn't usually punctual in casual settings, but he never disrespected mission time. This was Anbu protocol. Being late on the field could mean failure—or death. Even he wasn't that reckless.

"Alright, everyone's here. Let's move out," Raidō said firmly.

No one objected.

At sixteen, Raidō was the oldest. Genma and Kakashi were both around fourteen. Ibiki was the youngest at ten, but already unusually stoic and analytical. These weren't just random selections—Minato had chosen them directly for his personal Anbu detail. They weren't the children of famous clans, but they had potential. More importantly, they were loyal.

It was unfortunate that Minato had died before he could truly mentor them.

Still, their selection into Anbu was proof of their ability. They weren't elites yet, but the foundation was solid. That said, Kakashi could still overpower all three with little effort.

After all, not everyone was Kakashi Hatake.

Despite his age, he was already approaching jōnin-level skill. With the Sharingan, he was nearly unrivaled below the Kage tier. If he unleashed Kamui… he could probably even defeat his future self from the early Shippuden era.

Then again, without the Mangekyō's power, he'd be on par with himself from twelve years later. A draw, perhaps.

But none of that mattered now.

Their mission had begun. The four masked shinobi dashed into the forest, vanishing into the canopy.

Kakashi found himself distracted by the immense trees around them—natural towers born of Senju Hashirama's legendary Wood Release. It was awe-inspiring. Creation was always harder than destruction. The First Hokage hadn't just been a powerful ninja; he was an era-defining miracle.

Five days later, the group arrived at the border between the Land of Fire and the Land of Lightning.

"Whew, finally here. My legs are killing me," Raidō groaned as he perched atop a wide branch, scanning the horizon.

They were young, and five straight days of travel had taken its toll.

Kakashi, however, didn't feel much fatigue. He'd endured worse.

More importantly, he had used the journey wisely.

All three of his teammates had trained under Minato. They didn't know the full intricacies of Flying Thunder God, but they remembered how Minato had explained its concepts.

Kakashi had used this opportunity to "review" Flying Thunder God with them—disguising his questions as collaborative study.

None of them found it odd. Kakashi was Minato's direct disciple, after all. It made sense he would study the technique. And his insight into the jutsu seemed profound enough to convince them that he'd been learning it for years.

But only Kakashi knew the truth. He had only just unlocked the secret of Flying Thunder God.

And he understood now why Minato hadn't taught it to more people.

Knowing the formula wasn't enough. You needed the reaction speed, the spatial awareness, the combat intuition. Even among geniuses, Flying Thunder God could remain out of reach for a lifetime.

Minato knew these three wouldn't master the jutsu on their own. But by teaching it to them as a trio, he had hoped they could use it cooperatively. That was also why he had grouped them together—to foster teamwork, to lay a foundation of synchronized tactics.

They weren't just students. They were pieces in a larger strategy.

Minato's legacy lived on—not just through jutsu, but through the people he'd trusted.