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In an instant, Imu vanished from where she stood.

A heartbeat later, she reappeared directly before Ron—her blade flashing as she struck, sending him hurtling through the air with a single slash.

"Teleportation? No… even spatial movement leaves traces. There's no way that could escape these eyes."

Blood blossomed from Ron's chest as he was flung backward, spinning through the air. His piercing azure eyes locked onto Imu, now standing where he had just been.

A bold thought surged through his mind.

"Could it be… she twisted time itself?"

Yes—that had to be it.

She hadn't moved at lightspeed. Instead, she had folded time, compressing the interval it would've taken her to reach him. To Ron, it merely looked like she had appeared in front of him in an instant.

That was the only explanation that made sense.

Because with his Transparent World, Observation Haki, and those Tenseigan eyes—there was no way he wouldn't have seen any sign of her approach!

Ron landed hard, sliding across the shattered earth, boots carving deep scars into the stone. Blood dripped from his wound, but he paid it no mind. His gaze remained locked on Imu.

"She can twist space… and now time too? This ability… is utterly broken."

There was no question now.

This was the power of a fully awakened Devil Fruit.

Across the battlefield, Imu gazed at Ron—whose chest wound was already beginning to close, the flesh knitting together before her eyes. For the first time, a flicker of doubt passed through her deadened stare.

Was that really a human body?

Her strike had been precise—lethal. She meant to cut him clean in half.

But his resilience… had far exceeded her expectations.

He had reacted just in time, pulling back, and so her sword had only torn open his chest, not reached his vital organs.

Still, it was no minor wound.

For a human, such rapid regeneration should be impossible.

Even Zoan-type awakenings couldn't recover that fast.

Not unless—he was a monster on the level of Kaido.

And indeed… with a vitality stat now beyond 5,000, and having perfectly fused with the legendary Sage Body, Ron's life force rivaled even Kaido's so-called immortality!

Fifteen seconds after the strike—

Ron stood tall upon the ruined ground. His long black coat billowed open, the wind weaving through his inky-black hair. His chest, exposed by the torn front of his shirt, revealed a lean, powerful musculature. The ghastly sword wound… was gone. Not even a scar remained—only a few streaks of blood stained his skin.

He gripped his crimson blade in his right hand, and smiled toward Imu.

"That last attack… how many more times can you pull it off?"

Imu said nothing.

Before another word could be spoken, Ron vanished—no sound, no warning.

Imu, too, blinked out of sight at that same moment.

In the very next instant—

They appeared in mid-air, blades drawn, and clashed with all the fury of gods.

Before sword met sword, their Haki clashed first.

BOOM!

A deafening pressure shock exploded outward.

Crimson and blood-red lightning bolts curled and twisted around their figures, streaking across the sky in a chaotic web of destruction.

Below them, the ground was torn apart in an instant.

The entire castle of Mary Geoise was leveled by the shockwave—the mighty structure reduced to rubble.

Even Shanks and Black Dragon, who were locked in their own fierce duel, were blown away by the force.

In the skies high above Mary Geoise, ten thousand meters up, the sea of clouds burst open, forming a gaping hole over a kilometer wide.

BOOM—BOOM—BOOM!

The very earth trembled, roaring in agony.

A massive rift split open beneath them—so deep it seemed to stretch into the bowels of the world itself.

It was as if the entirety of Mary Geoise was about to be split in two.

And if that rift continued to spread…

Then the Red Line itself would be torn asunder—creating a vast canyon that would link the first half of the Grand Line to the New World.

A flicker of divine light flashed across Ron's azure eyes.

The shockwave blasted Imu away, sending her flying.

And then—Ron reached out.

From the very air before him, he pulled a blade from the void.

Black Blade—Shusui.

Now dual-wielding: his blood-red Sword in one hand, and the legendary Shusui, forged pitch-black with Armament Haki, in the other.

The winds howled.

His coat flared.

The very air trembled as Ron took a deep breath—

And activated the mightiest form of his sword style:

"Sun Breathing—Final Form."

"Dual Blade Style – Sun Breathing Ultimate Art…"

"Purgatory: Heaven and Earth to Ashes!"

The end had come.

As Ron's eyes glowed with a fierce red hue, he brought down his two purple-black long blades, each wreathed in boundless Haki and terrifying sword aura.

The very temperature of the world surged.

Two monstrous slashes—one pitch black, one crimson red—each stretching thousands of meters, tore through the sky in the shape of a cross, burning with unquenchable black flames. Like the strike of a god splitting the heavens, the twin slashes descended directly toward Imu from above.

The entire sky was painted in shades of deep black and glowing crimson by the swing.

Every soul who witnessed this strike trembled in awe and horror.

Up in the air, Imu's gaze sharpened. She raised her hand and pressed forward.

A monstrous, reality-bending power erupted around her, warping and shattering the very space into a spiraling shield of distortion—her final line of defense.

BOOM!

The cross-shaped slash crashed heavily into the warped spatial barrier. Space cracked and collapsed further, breaking like shattered glass under the weight of sword energy and black inferno.

Endless black flames and sword aura streamed into the void through the fractured dimension, and some of the purgatory fire escaped through, trailing like meteors across the sky.

Seeing that the attack had been blocked—

Ron's thoughts moved like lightning. He swung his sword again.

But Imu blinked—and vanished.

She appeared again, suddenly and without warning, directly in front of Ron.

This time, she stretched out her hand—her palm brimming with terrifying, twisted energy—as she lunged to tear Ron's body apart with the raw force of spatial collapse.

But—

Ron's eyes shimmered with divine brilliance.

A pitch-black Truth-Seeking Orb materialized between her palm and his chest.

The moment Imu's hand approached it, the overwhelming spatial force she had gathered was completely devoured by the black sphere, as if swallowed by a miniature black hole.

A rare flash of shock crossed Imu's face.

WHOOSH!

Without giving her time to react, Ron's right leg, hardened with the full force of Armament Haki and shadow-black like obsidian, whipped through the air with a thunderous boom. Wrapped in sheer pressure, his foot smashed squarely into Imu's body.

CRASH!

Imu's figure was sent hurtling toward the ground like a falling star.

She slammed into the surface of the Red Line with bone-shaking force.

BOOM!

The indestructible bedrock of the Red Line trembled violently.

First, a crater over a dozen meters wide caved in.

Then, the land within a hundred meters depressed in.

Then five hundred meters around her impact site sank like a pit collapsing in layers.

One after another, like a ripple of earthquakes.

Hovering above the crater, Ron raised his hand and hurled the Truth-Seeking Orb down into the pit.

KRA-KOOM!!!

The explosion that followed was like a nuclear detonation—an annihilating force that shook the very core of the Red Line.

The entire battlefield around Mary Geoise froze.

Even Shanks and the Black Dragon halted their clash and turned toward the cataclysm.

As the clouds of dust and debris gradually faded—

Ron hovered mid-air, his black coat fluttering in the high winds, overlooking the titanic crater torn into the heart of the Red Line.

But there was no sign of Imu.

Ron's brow furrowed ever so slightly.

And then—

A suffocating, god-like aura erupted above him.

He looked up—and his pupils narrowed.

There stood Imu in midair, garbed in her flowing black robes. Her presence warped the air itself. The space around her twisted uncontrollably, like a heat haze, rendering her silhouette flickering and unstable—like a reflection on disturbed water.

At that moment, her dark robes danced violently in the storm.

Her eyes were cold and unfathomable—like an ancient deity returning to rule.

Behind her, the sky had split—blood-colored cracks spreading across the heavens like a spider's web.

"That's… the second awakening of a Devil Fruit!"

The Five Elders looked up with faces full of reverence and fanatical devotion.

"This is Lord Imu's true power…"

"This is… the power of a god!"

…

Elsewhere, Zéphyr, Rayleigh, and others watched on with grave expressions.

"To think such an overwhelming level of power could exist in this world…"

"Can that kid… really win?"

Even Akainu, Fujitora, and Aokiji had paused mid-battle, gazes lifted toward the heavens.

A flicker of concern flashed in the eyes of Empress Hancock and Kuina.

It wasn't that they doubted Ron's strength.

It was just… the enemy was simply too terrifying.

At this moment, Imu had unleashed her full power. The twisted force surrounding her surged to an overwhelming degree, entwined with the highest level of Conqueror's Haki, forming a pressure so great it distorted the very fabric of the world.

Everyone could feel that suffocating aura.

Some of the weaker Marines collapsed on the spot, unconscious. Even seasoned veterans—battle-hardened officers—struggled to stay conscious, some even falling to their knees as if compelled to bow.

Even Ron felt the weight pressing down on him.

High above, Imu's gaze was cold and void. She raised one hand… and pressed down toward Ron.

An invisible, colossal finger of twisted energy descended from above, its might so terrifying that the space in front of Ron shattered like brittle glass.

He felt it immediately—space was being bent and warped.

No chance to evade with spatial movement.

"So I'll have to take it head-on…"

Ron exhaled softly.

"Well then—guess it's time I stop holding back too."

Ever since the fierce battle on Onigashima in Wano, he hadn't used his full strength.

As divine light blazed within Ron's sky-blue Tenseigan, a massive burst of green chakra erupted from his body, engulfing him completely. Several orbs of Truth-Seeking Balls floated in orbit around him.

Tenseigan. Chakra Mode—Activated!

Essence of Strength Lv. 5—Activated!

Breath of the Sun—Flowing!

Wreathed in divine green chakra, his hair billowing like a god descending from the heavens, Ron raised the blood-red Blade now shrouded in swirling green chakra. Three of the orbs transformed—shifting like flowing black mercury to spiral around the blade.

In this moment, Ron stood in his ultimate form.

And then—he brought the blade down.

A blinding beam of sword energy, thick as a mountain and straight as a divine pillar, surged skyward—meeting the terrifying finger of twisted power head-on.

BOOM!

The collision of their powers was cataclysmic—like two primordial gods locking arms. Space between them collapsed inward into a gaping black void, utterly destroyed.

And then, in an instant, it all exploded—like a pair of nuclear suns colliding.

Countless stunned eyes watched in total silence.

Mary Geoise was obliterated—reduced to rubble in a single strike.

As the smoke and dust faded, the top of the Red Line had vanished.

In its place… was an enormous chasm that stretched endlessly from one end of the horizon to the other.

Ron stood in midair, though his beloved blade, Blood Moon, was now shattered beyond repair.

He switched to his final weapon—his black blade, Shusui—and exchanged a flurry of strikes with Imu.

But even Shusui, the legendary black blade, couldn't endure. It too… cracked and broke.

And still, the battle was not yet over.

Both warriors now faced each other… ten thousand meters above the surface, suspended over the sky like gods warring over the fate of the world.

"Dimensional Tempest."

Imu's voice was calm—cold.

She gathered every ounce of twisted power within her, forging her most devastating technique yet.

Ron, already pushing past his limit, didn't retreat.

Instead, he summoned more—dozens—of Truth-Seeking Orbs. With a gesture, he fused them into a single, blinding golden chakra blade.

And then, from above the world…

"Golden Wheel Reincarnation Explosion!!"

That day…

The world watched.

And they witnessed it:

A golden divine blade, descending from the heavens.

It split the Red Line and the surrounding ocean for thousands of miles.

The land cracked open.

A massive canyon was carved right through the Red Line, stretching from the Grand Line's beginning all the way to the New World.

No longer did the currents pass through Mary Geoise.

From then on, the sea currents flowed through that canyon instead—a new route, forged by godly power.

That place would one day be named:

The Demon's Ravine.

Others would come to call it:

The Valley of the Traveler.

The Valley of Origin and End.

…

[Author's Note:]

With this, the main arc of the One Piece storyline comes to a close.

If I continue now, it might feel like filler, so I'll save the rest for a special epilogue later—covering Fishman Island, the fate of Ron's Crew, the remaining Four Emperors, and of course… what happens to Luffy.

Up next—

We'll move into the Demon Slayer world. After all, we did start off with the Breath of the Sun, didn't we?

That's all for now.

This was my first time writing One Piece-based fiction, and I'm sure it had its flaws. But thank you so much for reading this far.