Mokuton Phantom in Naruto

The cave was utterly silent. Only the rhythmic drip of water from stalactites broke the darkness, echoing faintly in the hollow chamber.

In the center of the cave, atop a slightly elevated rocky platform in the middle of the underground lake, Ryuusei prepared the seal.

He pressed his palm against the damp ground, chakra flowing steadily as he traced a complex circle with six empty slots.

"Kyūyū Fūin…"

It was a sealing technique taught by his grandmother, Keiko Uzumaki. A fūinjutsu designed to absorb and redirect chakra. But now, he was about to attempt something new.

Carefully, he picked up the bluish-green fragments he had extracted from the cave wall.

They still pulsed faintly, radiating the same strange energy he had felt in the river.

One by one, he placed the fragments into the slots of the seal.

The circle glowed softly as the minerals settled into place.

The energy began to react.

Ryuusei sat in the center of the seal, closing his eyes.

If this power was similar to the Star's…

Then he could master it too.

He took a deep breath.

His body was already accustomed to Star Energy, so he felt no discomfort as he drew this new power inward.

He began to meditate, using the same technique he had learned in Hoshigakure.

Slowly, the energy flowed into him.

It was strange, but not painful.

His chakra expanded, filling him like a warm current.

Ryuusei opened his mind to the flow of energy.

Hours passed.

And then, something changed.

Without warning, a surge of intense rage flooded his body.

His muscles tightened.

His fists clenched so hard that his nails dug into his skin.

He snapped his eyes open.

And saw everything bathed in red.

"What…?"

His heart pounded violently.

Breath came in ragged gasps.

An unstoppable fury climbed his spine, consuming every thought.

A primal growl rumbled in his throat.

"Why am I… so angry?"

The need to destroy overwhelmed him.

He moved before he could think.

With a furious roar, he threw a punch at the cave wall.

BOOM!

The rock shattered.

Cracks spread like spiderwebs across the surface before a massive chunk collapsed, crashing into the lake below.

Ryuusei staggered back, gasping for breath, shocked by his own strength.

"This…"

"This would've been impossible for me normally."

His fists trembled.

The ground around the Kyūyū Fūin was fractured, and the lake's surface rippled from the unleashed energy.

Finally, the pressure within him ebbed.

He stumbled out of the seal's circle, mind clearing as the energy ceased its flow.

Bit by bit, his heart slowed.

The rage dissipated.

Ryuusei inhaled deeply, regaining control.

Kneeling by the lake, he splashed cold water on his face, savoring the instant relief.

But when he lifted his gaze to his reflection, he froze.

His eyes were no longer blue.

They now glowed with a faint orange hue.

And around them…

A red shadow had formed.

Ryuusei stared at his reflection, the orange eyes gleaming faintly beneath the cave's dim light.

The crimson aura remained, a stark reminder of the transformation he had undergone.

His heart still raced.

The memory of that uncontrollable fury lingered vividly in his mind.

The punch he had thrown had demolished solid rock as if it were paper.

That… wasn't normal.

"I've never had that kind of strength before."

What would happen if he could harness that power at will?

If he could control it completely…

But the danger was clear.

The rage had consumed him instantly, clouding his judgment.

If he tried again, could he resist it?

He needed a new method.

Something to keep him grounded, to prevent the energy from taking over.

Ryuusei stepped away from the lake, returning to the seal he had created at the cave's center.

The Kyūyū Fūin still glowed faintly, the minerals quietly channeling the strange energy.

He sat down once more within the seal's boundary.

But this time, he would go a step further.

With swift hand signs, he molded new seals in the air.

"Fūinjutsu: Uzu no Kusari!"

The ground beneath him shimmered with spiraling patterns.

Suddenly, golden chains erupted from the floor, wrapping tightly around his arms, legs, and torso.

They coiled firmly, locking him in place at the heart of the seal.

No matter how strong he became, he wouldn't escape.

At least… that was what he hoped.

It was a brutal method.

But a necessary one.

"Now… let's see if I can stay in control."

Ryuusei closed his eyes and began absorbing the energy once more.

The familiar warmth spread through his body, filling every muscle.

His breath grew heavy.

But this time, he focused on the changes.

What exactly was happening inside him?

His chakra felt… different.

He could sense it circulating, as though something was refining it.

Making it denser, rougher.

His cells vibrated.

Like they were strengthening on their own.

"This isn't just regular chakra."

Star Energy boosted Hoshigakure shinobi's strength.

But not like this.

This energy wasn't just enhancing him.

It was altering him.

His wounds healed faster.

Fatigue vanished almost instantly.

Was it enhancing his natural Uzumaki resilience?

Before he could reflect further.

The rage returned.

A guttural roar tore from his throat.

His body trembled violently.

He wanted to break free.

To destroy everything around him.

But the chains held firm.

"Damn it… AAAAAH!"

The hatred burned like fire in his veins.

He yanked against the chains with all his might.

They creaked under the strain.

But didn't break.

Panting, teeth clenched, Ryuusei forced himself to think.

"I need to understand this energy."

"Absorbing it mindlessly will never teach me control."

He shifted his focus inward.

Where was the rage coming from?

Why did this energy spark such destructive instincts?

Gradually, patterns began to emerge.

The anger didn't appear out of nowhere.

It grew as the energy spread through his body.

It wasn't just strengthening him.

It was forcing him to adapt.

"That's it…"

He wasn't simply absorbing a new type of chakra.

His body was being evolved.

Perhaps the villagers' unique traits were the result of generations exposed to this energy in small doses.

And perhaps the uncontrollable side effects stemmed from his body struggling to adapt to the change all at once.

He needed to adapt without losing control.

Ryuusei closed his eyes once more.

This time, he didn't resist the energy.

He didn't fight the rage.

Nor did he try to dominate it.

He simply let it flow.

Like a river passing around a stone.

Bit by bit…

The pressure eased.

His breathing steadied.

The chains stopped groaning under strain.

And his eyes.

The orange glow softened.

The crimson shadow remained, but it no longer clouded his vision.

It was no longer a mark of blind fury.

It was a sign of control.

Ryuusei exhaled slowly.

He hadn't fully mastered this power.

Not yet.

But now, he knew where to begin.

The energy itself wasn't the problem.

The issue was how his body reacted to it.

Like oil and water clashing, the rage was the result of two incompatible forces colliding.

The same thing happened in Hoshigakure.

The negative effects arose because the Star Energy was being forced into bodies unprepared for its influence.

But the Uzumaki's blessed genetics gave Ryuusei an edge.

Even if his body wasn't fully adapted, his regeneration allowed him to endure the backlash.

"If I can acclimate to this transformation, I can use it consciously."

He glanced down at his hands, still bound by golden chains.

If he wanted true strength…

It wouldn't be enough to absorb the energy and wield its raw power.

He needed to understand it.

What was this energy?

Was it present everywhere?

Hoshigakure's power stemmed from the meteorite that fell centuries ago.

But this cave was isolated, untouched by human hands.

"So… is a high-energy location required? Somewhere without human interference?"

No.

Hoshigakure didn't meet that requirement.

The meteorite somehow concentrated the energy.

Otherwise, it would have dissipated after generations of being drained by the village.

Ryuusei tightened his fists.

"If I can figure out how the meteorite concentrates this energy…"

"I can unlock strength no one else has ever achieved."

And this time.

He would master it without losing himself.

The path was clear.

And he was ready to walk it.