The Infinity Castle thundered with clashing wills. The battle between man and monster had fractured into storms of blood, flame, and steel.
Akaza's fists slammed against Rengoku's blade, shockwaves ripping apart the floor beneath them. The Upper Moon's body glowed with destructive energy, every strike carrying the weight to pulverize mountains. Yet Rengoku's fire blazed brighter. His katana was an inferno, each swing burning not just with strength but with his unyielding heart.
"Your fists cannot extinguish my flame!" Rengoku roared, fire igniting across the battlefield.
Akaza smirked, blood dripping from split knuckles. "Then burn, Kyojuro Rengoku! Burn until nothing remains!"
Their clash became an infernal storm, each strike louder than the last—two wills colliding in a firestorm that seared the eyes of every slayer nearby.
Across the chamber, icicles rained like death as Douma danced with cruel elegance. Shinobu moved like lightning between the shards, her blade piercing his flesh in swift, venom-laced strikes. Her small frame was a storm of precision, every stab angled for organs that demons should not have survived.
Douma only laughed, his voice mocking and cold."Your poison is delightful. So persistent, little insect… Perhaps I'll preserve you in ice for eternity."
Shinobu's glare burned with fury. "You won't take another life—not while I still breathe!"
Her blade darted forward, finding seams in his defense. For every wound she carved, his body stitched itself back together in mocking defiance. But her determination only sharpened, venom flowing stronger than before.
At the center of the battlefield, Tharion's duel with Muzan was apocalyptic. His aura surged, a dome of fire bursting outward every time his blade struck. Each swing burned thousands of demons to ash, leaving craters of molten ruin in the Infinity Castle's endless body.
Muzan sneered as his flesh regenerated faster than fire could consume it. "You burn brightly, interloper—but even the sun will fade before me."
Tharion's masked gaze was unyielding. His power limiter gone, every movement carried divine fury. "If I must burn until the stars go dark, then so be it."
The firestorm of their battle lit the castle like a second dawn.
And then… Murata.
Kokushibo had stepped into his path, six eyes gleaming with disdain. The Upper Moon's blade whispered free of its sheath, the weight of centuries pressing down on the ordinary slayer before him.
Murata's hands shook. His blade felt heavy. Around him, comrades screamed, demons howled, the world fractured into chaos.
And then something within him—something ancient—stirred.
His lungs expanded. His pulse aligned with something greater than himself. The universe seemed to hold its breath.
He raised his sword.
The air shimmered, constellations flickering in his wake. His blade cut through the darkness with brilliance not of this world.
"Breath of the Galaxy," Murata whispered, the words not his own but carved into the marrow of his soul.
The slash erupted like a river of stars, an arc of celestial light that split the battlefield. Kokushibo's six eyes widened as the attack cut across his guard, forcing him to retreat for the first time in centuries.
The gods watching beyond the veil of worlds froze.
[The System trembles.][Divinity Report: Unknown Breathing Style detected. Cross-reference: Lost record from destroyed Earth. Galaxy Breathing.]
Even Tharion, mid-duel with Muzan, turned his masked head in shock. His flames faltered for a fraction of a second. He had read every manga, every story—but this style never existed. It was fiction within fiction, an imagined art that should not breathe in reality.
Muzan sneered, sensing his moment. "Distracted already?"
Tharion forced his fire higher, slamming Muzan back against the wall. But his mind reeled.
The gods themselves whispered across the void, their voices trembling. "Impossible. A breathing style that was never confirmed… now alive? How?"
Galaxy Breathing. A style whispered by fans, never canonized, but etched into the fragments of imagination from Tharion's lost Earth.
And now, Murata—the unremarkable slayer, the man overlooked by history—had awakened it.
Stars burned in his eyes. His aura rippled with infinity.
Kokushibo steadied himself, lips curling into a grin. "At last… a worthy opponent."
The Infinity Castle trembled again. The battle was far from over.
The Infinity Castle pulsed with chaotic life, walls shifting like a beast's innards, the air heavy with the stench of blood and ozone. Every corner of the battlefield was drenched in screams, clashes, and the brilliance of clashing Breathing Styles.
The rematch between flame and martial chaos had long abandoned the pace of human eyes. Rengoku's sword burned arcs across the void, his fiery aura cutting like a second sun in the suffocating dark. Akaza laughed, blood painting his jaw, his fists hammering the air with explosions of shockwaves.
"You've grown weaker, Flame Hashira!" Akaza taunted, even as blood poured from his abdomen where Rengoku's strike had torn through.
Rengoku grinned through grit teeth, his flame sword humming with purpose. "No… you've mistaken resolve for weakness. Tonight… I burn brighter than ever!"
Their clash split the shifting halls, flame pillars rising against the endless tide of Akaza's Destructive Death arts. Every strike wasn't just blade against fist—it was two worlds colliding, the choice between humanity's fragile hope and a demon's eternal, hollow power.
Far above, frost bloomed like creeping death. The ice lotus fields spread as Dōma's voice rang out with mock cheer. "My, how pitiful! The little insect still dances before the storm. How long before your wings freeze, Shinobu-chan?"
But Shinobu's eyes gleamed, venomous determination behind her smile. "I don't need brute force to kill you, Upper Two. My entire body… my entire being… is poison crafted for this one moment."
Her blade flickered in countless thrusts, each too fast to follow, needle strikes seeking the tiniest gap in Dōma's body. Frost gathered on her blade, her lungs burned from the chill, yet she pressed on.
Dōma chuckled, even as faint cracks of violet poison began spreading under his skin. "How delightful. Let's see how far you can dance before the cold stills your heart."
And then—the impossible.In the far hall, Kokushibo's crescent moon slashes carved through pillars like wheat stalks. His six eyes locked onto Murata, who stood shaking, knuckles white around his sword. To Kokushibo, he was nothing—an ant amidst gods.
But then, something awakened.
Murata inhaled, his chest glowing faintly as if he had swallowed a fragment of the night sky. His blade shimmered, not with fire, or water, or wind—but with an infinite void dotted by countless stars.
"Galaxy Breathing… First Form: Stellar Horizon!"
The strike carved through the Infinity Castle like a blade through silk. Light cascaded outward, stars birthing themselves from his arc. Kokushibo's eyes widened—true surprise flickering across his ancient face—as his Moon Breathing clashed against this newborn galaxy.
"Impossible…" Kokushibo hissed, his crescent blades meeting Murata's sweeping universe. The impact shattered the floor beneath them, constellations scattering across the void, moons and galaxies devouring each other.
High above, even gods who once silently observed the battlefield stirred, their gazes flickering downward. They had seen this before, long ago—on the destroyed Earth of another cycle. The forbidden breath of a universe lost.
Tharion, locked in his duel with Muzan, faltered for a heartbeat, his masked eyes narrowing. Galaxy Breathing… here? Now?
On another platform, Tanjiro and Zenitsu held their breath as the battles raged, their eyes catching glimpses of the impossible clash. Beside them, Inosuke's chest heaved, his wild boar mask tilted just enough to reveal trembling lips.
Zenitsu, wide-eyed, stammered. "I-Inosuke… you're shaking. What is it? You've never… looked like this before."
For once, Inosuke's laughter didn't rise to cover the fear. Instead, his voice cracked, lower, rawer. "That demon… Dōma… I remember him. The scent… the face. He's the one who killed my mother."
Tanjiro's eyes widened, his heart sinking with the weight of revelation as he glanced at Shinobu locked in her deadly ballet with Dōma.
Inosuke's hands clenched around his dual swords, the beastly fire in his eyes flaring as he growled. "I'll rip him apart. For her."
Back in the distance, Galaxy clashed against Moon. Rengoku's fire roared against Akaza's fists. Shinobu's poison danced against Dōma's frost.
And in the heart of it all, Tharion and Muzan tore at each other like gods in a cage of demons.
The war had begun in full.