Naruto: Limitless Sage

Back at the training field—

Kakashi was still reeling from Naruto's performance.

But unlike before, he didn't waste time pretending to be aloof or stubborn.

He was ready.

Fully prepared to learn the "Thunder Sword" from Naruto, without hesitation.

He knew—

If he could master this blade, and fuse it with the Hatake clan's White Fang sword technique...

Then his strength—

Wouldn't just rise to Kage-level.

He might actually break through to the peak of the Kage tier.

A place few ever reached.

And Naruto?

He welcomed it.

After all—

If the boss has to handle everything himself, doesn't that just make him a glorified errand boy?

Strengthening Kakashi meant more freedom for Naruto.

Fewer loose ends.

Fewer jobs to do personally.

And so, the clone began to teach Kakashi step by step:

Step One:

Improve your lightning chakra quality. Sharpen it. Refine it. This is the foundation.

Step Two:

Learn to maintain high-frequency vibration of that lightning in the palm of your hand.

Step Three:

Fuse both elements to create the Thunder Lightning Sword.

It sounded simple.

But this technique—

This weapon that could overpower even S-rank jutsu—

Also came with a training difficulty that exceeded S-rank.

But.

Fortunately…

Kakashi had one hell of a teacher.

And Naruto?

He had all the time in the world.

Kakashi had been a famous genius in Konoha since his youth.

In terms of talent, he was definitely among the top shinobi the village had ever seen.

And now, with Naruto—a teacher possessing extraordinary insight—personally guiding him, Kakashi's growth, though a little slow at first, was steadily getting back on track.

Meanwhile—

While one of Naruto's clones trained with Kakashi…

Another clone…

Was "helping" Sasuke cheat his way into learning Sage Mode.

Konoha Village.

In front of a waterfall at a secluded training ground—

Naruto's clone and Sasuke sat cross-legged on two flat bluestone slabs. The roar of cascading water filled the air, grounding them in nature.

Naruto calmly began to explain Sage Mode:

"All around us, the air is filled with an endless flow of natural energy."

"This energy comes from the earth beneath our feet."

"As long as the world exists—natural energy will continue to emerge."

"It's a power even more advanced than chakra."

Sasuke's eyes widened slightly. To think there was a force stronger than chakra itself—it was hard to believe.

But he said nothing.

He didn't want to interrupt.

Naruto continued:

"That's right. The conditions to enter Sage Mode are extremely strict."

"Since the beginning of the ninja world, very few shinobi have managed to master it. You could probably count them on one hand."

"First—you need the talent to even sense natural energy."

"Second—you need a mental state far beyond that of the average shinobi."

"And finally…"

"You must have complete control—fusing natural energy with your own spiritual and physical energy."

"If you can't manage that… the natural energy will devour you."

At that last line, Sasuke felt a heavy pressure settle over him.

He believed Naruto. He'd never heard of Sage Mode before. And there had never been any mention of it in the Uchiha clan's archives.

That alone proved how rare it must be.

Only a few in the entire ninja world could master it.

But—

Even though Sasuke felt the weight of how difficult it would be…

When he thought about his goals…

His revenge…

He clenched his fists.

He wouldn't back down.

He would face this challenge head-on!

However—

Just as Naruto finished explaining everything with a serious expression…

A grin suddenly crept across his face.

"But."

"That's for other people. I'm different. I've got a way to help you cheat."

Naruto's tone flipped from heavy to casual in an instant.

The shift was so sharp that Sasuke nearly fell into the waterfall.

"Naruto!!"

He'd just gotten into the mindset! Had just hyped himself up! Had mentally committed to enduring whatever hell it would take!

And now Naruto was telling him there was a shortcut?

Of course, Sasuke knew Naruto meant well.

He wanted to repay Naruto.

But still!

He definitely got played just now!

He was furious.

But he couldn't say anything.

He just puffed up in frustration.

Naruto, watching Sasuke sulk with his cheeks puffed out, couldn't help but laugh.

"Little Sasuke, little Sasuke~"

"Alright, alright. I won't tease you anymore."

"Just remember to repay your big brother someday."

Naruto spoke—

Then walked behind Sasuke.

Hearing that, Sasuke didn't say a word. He sat obediently, not daring to interrupt.

But he knew what was coming next.

Naruto was about to help him… using that special method he'd mentioned.

Immediately, Sasuke perked up, his expression becoming serious.

He was ready.

Naruto didn't bother hiding the faint smirk tugging at his lips.

As for that special method?

It was simple.

To learn and master a new power…

Experiencing it firsthand is always the fastest shortcut.

So, without any further explanation, Naruto fixed his gaze on Sasuke—and began drawing in a massive surge of natural energy from all around them.

From the water.

From the earth.

From the very sky.

In that instant—

A torrent of raw natural energy flooded toward them, pulled by Naruto's will.

Then—

It surged directly into Sasuke's body!

Sasuke immediately felt it—

A massive, overwhelming force was pouring into him from all directions. Wild, intense, and completely alien.

He had to focus.

Fast.

He worked to stabilize the energy, to bring it under control.

And to his surprise…

He could control it. Just like that.

In that moment, had Sasuke glanced at the surface of the water—

He would have seen his reflection.

And on his face…

Around his eyes…

A faint lavender pigment had appeared.

The unmistakable mark of someone who had entered Sage Mode!

Then, Naruto's voice came from behind:

"Don't get too excited. What I gave you is basically a trial card—good for about a minute."

"You've got one minute to experience Sage Mode."

"So focus. Try to feel everything about it."

"This is your chance to understand Sage Mode from the inside."

Naruto returned to the bluestone slab and sat down again, his tone casual.

Sasuke turned to him, slightly flustered.

"Then what should I do?" he asked.

He hadn't expected this to be the so-called special method.

Naruto's answer was direct:

"Use your Fire Style."

Sasuke understood instantly.

Sage Mode energy was superior to regular chakra.

Which meant the jutsu released using it—

Would be stronger too.

That realization sent a thrill through him.

Without hesitation, he turned to face the waterfall.

It stood like a tower—thirty meters wide, and at least a hundred meters tall, crashing into the river below with unstoppable force.

A natural fortress.

Sasuke narrowed his eyes.

Then he moved.

His hands flashed into seals—

Tiger → Boar → Monkey → Horse → Dragon → Ram!

He began gathering the immense Sage chakra surging within him.

His lungs filled as he took a deep breath, mixing oxygen with chakra—

And then—

"Senjutsu: Fire Style—Great Fireball Jutsu!!"

Sasuke roared—

And a massive fireball exploded from his mouth!

What shocked Sasuke the most—

Was the sheer power of the fireball he had released in Sage Mode.

Its size had increased dramatically—by dozens of times!

Normally, the explosion range of his Fire Style: Great Fireball Jutsu would be around the size of a rooftop.

But now?

Before even detonating, the fireball was as massive as the top of a mountain!

It was so huge, it completely obscured Sasuke's view of the towering waterfall ahead.

And the heat—!

It rolled off the flames in waves, scorching the air and making it feel like his skin might burn.

BOOM!

The next moment, the fireball collided with the waterfall—

A deafening explosion echoed through the forest!

Torrents of water were vaporized on the spot, throwing up clouds of white-hot steam.

The once-raging waterfall—

Was momentarily interrupted mid-fall, leaving a bizarre vacuum in its flow.

The waterfall had been cut in half.

Then—

Through the veil of rising mist, Sasuke spotted it.

A massive crater, blasted directly into the rock face behind the waterfall.

If that fireball had landed in a real battle?

In the middle of a crowded battlefield?

There was no doubt—

It would have annihilated entire enemy units in an instant.

And Sasuke knew better than anyone—

His regular fireball, without the boost from Sage Mode, could never come close to this kind of destruction.

"So… this is Sage Mode?"

Sasuke muttered to himself, stunned. "This is insane…"

From where he sat, Naruto watched quietly, a smile tugging at the corner of his lips.

He couldn't help but think:

As expected of the Reincarnation of Indra…

In the original timeline, Sasuke had obtained a flawed imitation of Sage Mode—through Orochimaru's Curse Mark.

Even then, that half-baked version had allowed him to fight Naruto, who was wielding the Nine-Tails' chakra.

It proved something:

Even a diluted form of Sage Mode gave incredible results.

And now?

With Naruto's direct intervention, Sasuke had temporarily tapped into true Sage Mode—perfect Sage Mode.

If just a single fireball could cause this much devastation—

Then it all made perfect sense.

Soon after—

The one-minute trial Naruto had granted came to an end.

Sasuke's Sage Mode faded.

His body returned to normal.

But that one brief moment was enough.

Sasuke had felt it.

And now, he began forming his own insights into what Sage Mode truly was.

Naruto, however, didn't let him use another trial right away.

Using the one-minute Sage Mode shortcut too often, especially without having adapted to natural energy, could cause serious backlash.

Once a day was the limit.

So, Naruto had Sasuke switch to traditional training—slowly learning to sense and harmonize with natural energy the normal way.

Surprisingly—

Sasuke didn't complain.

On the contrary, he welcomed the challenge.

He was grateful.

Because in this entire world—

How many shinobi could say they had a guaranteed path to mastering Sage Mode?

Sasuke etched this moment into his heart.

Naruto had shown him this path.

And one day, he would repay that debt.

While Naruto's clones continued helping Kakashi and Sasuke separately—

The real Naruto wasn't slacking off either.

In fact, he had a meeting today.

With none other than his father—Minato Namikaze.

They'd agreed to train together at a remote, abandoned training ground on the outskirts of Konoha.

Yes—

Today, Minato planned to pass down his signature jutsu:

The Flying Thunder God Technique.

Even though Minato knew that Naruto, at this point, was already powerful beyond compare—

Able to take down almost any enemy without even needing Flying Thunder God—

As a father, he still wanted to do something for his son.

Naruto, of course, didn't refuse.

Not only because it was a gift from his father—

But because, truthfully, he needed this technique.

With the Flying Thunder God in his arsenal—

Naruto could mark important locations all across the ninja world.

He could teleport anywhere in an instant.

That kind of mobility would be invaluable for his long-term plans of unification.

Just then—

"Naruto," Minato said, "do you know the true principle behind the Flying Thunder God Technique?"

Naruto shook his head honestly.

He had never studied it in detail.

Seeing this, Minato gave a small smile and replied:

"The Flying Thunder God… is actually a space-time ninjutsu, but at its core—"

"It's a type of summoning technique."

"Only..."

"The summoning technique was originally developed to allow us to call upon our contracted summoning beasts," Minato explained.

"But the Flying Thunder God Technique is different. Instead of summoning a beast... you're summoning yourself."

When Minato had first started learning the Flying Thunder God—

He'd been surprised.

The seemingly complex space-time ninjutsu was, at its core, just a variant of the Summoning Technique.

But—

The simpler something seemed on the surface, the more intricate it often turned out to be in practice.

"The reason most people can't learn Flying Thunder God," Minato continued, "comes down to one thing—perception."

"When you summon a beast, there's a spiritual contract involved. You and the creature can sense one another across space, creating a spiritual link."

"But when it comes to summoning yourself…"

"How do you perceive where you're going?"

"That's the core difficulty in mastering the Flying Thunder God Technique."

"You need to sense the location of the seal you've engraved—the Flying Thunder God formula."

"Only then, after extensive training and repetition, can you perform the teleportation technique flawlessly."

Minato paused at this point.

He wasn't exactly sure what Naruto's spatial perception capabilities were.

Sure, Naruto had once sensed the Third Hokage spying on him during a private meeting—a feat neither Minato nor the others had picked up on at the time.

But that kind of perception was different.

Sensing a hidden observer and sensing a spatial seal across a distance—especially one buried in dimensional space—were entirely different skill sets.

Ultimately, Minato knew that only Naruto himself could test his aptitude for this.

"Alright, Naruto," he said. "Let's start by teaching you how to carve your own Flying Thunder God seal."

Naruto, who had been listening attentively the entire time, nodded with focus.

And so, Minato began teaching him the first and most fundamental step: creating a personal seal—one that was uniquely his.

The design of the Flying Thunder God seal wasn't fixed. Every user customized it to suit their chakra and perception style.

The Second Hokage, Tobirama Senju, had his own formula.

Minato, the Fourth Hokage, had modified it to better fit his own technique.

And now—

It was Naruto's turn to create one that matched his unique ninja path.

Thanks to his natural talent and deep understanding of chakra flow—

Naruto learned how to design and engrave his personal Flying Thunder God formula almost instantly.

He chose to inscribe three elegant kanji characters—"Flying Thunder God"—with steady, bold strokes.

The calligraphy was majestic.

Minato blinked in surprise.

His penmanship is as refined as his power…

Still, that wasn't the point.

What mattered now—

Was practical application.

Minato directed Naruto to a tree several dozen meters away.

"Use chakra to inscribe your mark on that bark," he instructed.

Naruto did so without hesitation.

Then came the next challenge:

"Now, try to sense the mark you just made."

Minato didn't expect results right away. Even the most gifted shinobi often took days, even weeks, to make any progress.

But then—

Something unexpected happened.

You listened carefully as Minato Namikaze explained the principles of the Flying Thunder God Technique.

And then—

You had an epiphany.

You've mastered the Perfect Flying Thunder God Technique!

Perfect Flying Thunder God Technique:

A powerful space-time ninjutsu that enables instantaneous teleportation to any location marked with your personal Flying Thunder God seal.

At that moment, Naruto—thanks to his extraordinary perception and insight—immediately sensed the chakra mark he had just placed on the tree bark.

In the very next instant—

His body moved as though he had used the technique thousands of times before.

The moment he locked onto the seal—

Naruto's figure vanished in a blur of light.

And then—

Reappeared instantly in front of the tree, one hand now resting gently on the Flying Thunder God seal he'd just engraved into the bark.

"It worked!"

Naruto exclaimed, eyes wide in awe.

...

TN:

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