Ichigo took a step forward, his voice steady yet absolute. "You still don't realize it, do you? My strength has already surpassed yours."
In the blink of an eye, he vanished—reappearing in front of Aizen in an instant. His zanpakutō cut through the air with effortless precision.
Aizen barely registered the attack before pain erupted in his shoulder. A clean slash tore through flesh, and a spray of blood arced through the air.
His eyes widened, pupils contracting in disbelief.
He stared at Ichigo, whose calm expression carried a quiet superiority, as if he were looking down on him.
"Are you satisfied just because you stopped my sword?
Do you take pride in leaving a mere scar on my body?"
There was a flicker of anger in Aizen's voice, his hands trembling despite himself. Then, his expression twisted.
"Don't be so full of yourself, human!"
His head tilted unnaturally to the side, freezing in place for a moment. Then, with a slow, ominous pulse, his Third Eye gleamed—a crimson glow bleeding from its depths.
Suddenly, white pillars of light surged into the sky, engulfing him in an overwhelming force.
"Ahhh!"
The sheer agony in his voice made it clear—anyone could feel the suffering he was enduring. A gaping wound tore through his chest, a deep fissure cracked across his face.
Something grotesque erupted from his back.
A monster.
Three glaring eyes flashed as the pillar of light shattered under its pressure.
The peak beneath Aizen crumbled into dust, blood dripping down the ruins.
Aizen had changed.
Six monstrous wings unfurled behind him, each bearing a grotesque head. Blackened flesh twisted with sharp fangs, while six glowing eyes burned with eerie intensity.
His voice was now inhuman—a guttural, roaring snarl. "I will not be surpassed by a mere human!"
One of the winged heads opened its mouth, revealing a pulsating purple sphere.
Then—
A beam of pure destruction shot toward Ichigo at a speed beyond light.
"BOOM!"
A blinding explosion engulfed the battlefield. An inferno of unimaginable heat melted everything in its wake, leaving behind a towering mushroom cloud.
Aizen stood at the crater's edge, gazing through the flames.
Then he saw him—
Suspended at the heart of the firestorm, Kurosaki Ichigo stood unharmed.
Aizen's voice dripped with disbelief. "You took that full-on… and only lost an arm?"
Ichigo remained silent. His left sleeve was scorched away, his arm burned beyond use, but his gaze never wavered.
Aizen didn't hesitate. He shot forward, seizing Ichigo and dragging him from the flames.
Unfolding his monstrous wings, he spiraled upward, forming a cage of charged spiritual energy around them.
RUMBLE!
Above them, several more purple energy rings materialized, sealing Ichigo in a vortex of power.
Aizen's voice echoed. "Can you hear me, Kurosaki Ichigo?"
"You once transcended the barrier between Shinigami and Hollow… but in this state, you're beneath me.
You are nothing more than an offering to my ascension."
He was certain—erasing Ichigo would rid the world of this anomaly, this human who dared oppose him.
But—
Ichigo swung his zanpakutō.
CRACK!
The white rings shattered effortlessly, and Aizen was hurled backward by the sheer force of the counter.
Ichigo's voice was steady. "Enough of your delusions. This ends now."
Raising his zanpakutō, he pointed it directly at Aizen.
"This is… the Final Getsuga Tenshō."
A monumental surge of spiritual pressure erupted, piercing the heavens.
Aizen stood before the towering pillar of light, dwarfed by its sheer magnitude.
Through the glow, he could barely make out Ichigo's silhouette.
"What… is this?"
Time seemed to slow.
Ichigo emerged—
His form completely changed.
Long, dark hair flowed wildly, swept by the swirling torrents of energy. His body, save for his left arm, was wrapped in black bandages.
And his zanpakutō—
Gone.
Instead, darkness pulsed from his very being, raw spiritual energy overflowing from him.
Ichigo's voice carried an eerie finality. "This is the Final Getsuga Tenshō—because in this form, I become Getsuga itself."
"If I use this power… I will lose everything. My Shinigami abilities will be gone forever.
That is the meaning of 'Final'."
Aizen muttered, "And yet… I feel nothing.
I have evolved beyond both Shinigami and Hollow.
Like a higher-dimensional being untouchable by those beneath it…
You shouldn't even be able to affect me."
His memories flashed—his evolution, the Hōgyoku's fusion, the moment Gin stabbed him, and his final transcendence.
But then—
A horrifying realization struck.
Aizen's breath hitched, his voice trembling. "No… no, this can't be… Is he… standing on a dimension above me?"
His teeth clenched, grinding together in frustration.
"Impossible! A mere human… surpassing me?!"
Ichigo said nothing.
He merely raised his hand.
Dark spiritual pressure condensed into a blade of pure annihilation.
Aizen's body locked up, a deep instinct warning him—this was different from any attack before.
Ichigo swung his arm.
"Mugetsu!"
A wave of black destruction roared forward.
Hundreds of meters of spiritual pressure swallowed Aizen whole.
His eyes widened in disbelief—
Then, his body was split in half.
Silence.
The dark energy faded, revealing the battlefield in its original color once more.
A deep, precise incision stretched across the land.
Ichigo crashed to the ground, drained.
BOOM!
A distant explosion—
And Aizen still stood.
Though cleaved in two, his body pulsed, flesh twisting and reforming instantly.
Ichigo's gaze narrowed.
Shunpo.
In a flash, he was upon Aizen.
A roar erupted as Aizen's form violently shifted.
Then—
In an instant—
He reverted.
His monstrous features faded, his body returning to human form.
Ichigo, meanwhile, collapsed to his knees.
His bandaged right arm dissolved into dark spiritual mist, dispersing into the wind.
Aizen loomed over him.
"Kurosaki Ichigo…"
"You lost."
He lifted his broken zanpakutō, pointing it at Ichigo.
"You see… my blade is vanishing.
That means the Hōgyoku has deemed me unworthy of a zanpakutō.
It has judged that I have transcended its need.
I have ascended even higher than you—you who have lost your Shinigami powers!"
But—
A streak of red light pierced his chest.
Aizen froze.
Then—
Dozens of red energy spikes erupted from his body, pinning him in place.
Aizen's eyes narrowed. "What… is this?"
His gaze darted toward the source.
A man in wooden sandals stood calmly nearby.
Kisuke Urahara.
Ichigo's weak voice broke the silence. "Mr. Urahara…?"
Aizen's voice sharpened. "Kisuke Urahara… this is your doing?"
Urahara adjusted his hat, his tone measured. "Yeah. A seal I implanted in you before your transformation fully stabilized."
"When you were at your weakest, I embedded it through layers of Kido, waiting for the right moment."
"You see, Aizen…
It was never about defeating you.
It was about sealing you away."
Aizen sneered. "A foolish plan. Look at me—I am evolving again. Your Kido means nothing."
He raised his hand to shatter the seal—
CRACK.
His arm… fractured. Shattered.
Aizen's eyes widened.
"…What?"
Urahara's voice remained quiet, firm.
"The Hōgyoku is rejecting you.
Your power has diminished, Aizen. The Hōgyoku no longer recognizes you as its master."
Aizen's face twisted with rage.
"Ridiculous! I am—!"
His words died in his throat.
The final seal activated.
Light erupted, encasing him in prismatic swords.
Aizen roared, struggling against the binding Kido.
"KISUKE URAHARA!
With all your intelligence, why do you submit to this system?!"
Urahara sighed. "Because without the Soul King, the worlds would collapse."
"A loser's excuse!" Aizen bellowed.
Two glowing crosses formed behind his back. He strained, forcing movement, his will defying the unyielding binds. His free hand tore at the seals, but more formed in their place.
Still, he refused to be silenced.
"A true victor doesn't accept the world as it is but dictates what it should be! I refuse to bow to that Thing! I will decide how the world shall be!"
The light flared.
The seal fully formed.
Aizen was engulfed.
Three crossed blades hung in the air.
And—
The battle was over.
---
In a Grand Hall.
Amidst the towering walls of Central 46, a solemn assembly had convened. Discussions echoed through the chamber, but soon, all fell silent as an aged voice broke through.
"We shall now pass judgment."
All eyes turned to the figure bound at the center—the former Captain of the Fifth Division, Sōsuke Aizen.
"Aizen Sōsuke, for the crimes of high treason, betrayal of the Soul Society, and mass murder, you are hereby sentenced to 18,800 years of imprisonment in the deepest level of Muken."
The words settled like a heavy weight upon the chamber.
Aizen, bound to a chair, let the silence stretch before finally speaking.
"I see… But for the likes of you to judge me… isn't that rather absurd?"
The hall erupted in outrage.
"You damn traitor!" one of the council members spat. "You think you can look down on us just because you're immortal?"
"Extend his sentence—make it 20,000 years!"
"Agreed! Raise the sentence!"
And so, the final verdict was passed.
"Sōsuke Aizen, for your unforgivable crimes, you shall be imprisoned in the eighth level of Muken for twenty thousand years!"
The gates to Muken began to close, sealing him in darkness.
Inside, silence reigned—not the absence of sound, but a void so complete it erased even the concept of noise. A stillness that seemed to swallow reality itself.
'So this is my fate…'
He opened his only unsealed eye, staring into the endless abyss—an abyss that mirrored the void within him.
From the moment of his birth, he had been alone. The so-called geniuses of the world had never been anything more than fleeting distractions, insects scurrying beneath his feet. Even the rare few who had caught his interest—Kisuke Urahara among them—had ultimately disappointed him, shackled by their own mediocrity.
"In the end, it's still just me."
Bound to the solitary throne, he tilted his head slightly, a meaningless gesture in the darkness.
Twenty thousand years. Even for a Shinigami, it was an eternity. A punishment beyond the span of most lifetimes.
'Did those fools truly believe they could contain me? But… even if I were to escape, what then? The world outside is just another prison—larger, but no less suffocating.'
And yet, in that endless void, something stirred.
A faint, flickering light.
"Hōgyoku?"
The answer came immediately. The Hōgyoku—a creation born of his own ambition, a device that granted the deepest desires of its host—was responding.
By now, it had already become one with him.
"I see… it has sensed my wish."
A quiet chuckle escaped him. But even the Hōgyoku had limits.
'How could it possibly fulfill such a desire?'
Yet, the light persisted, gathering before him, coalescing into a shimmering void—an ethereal gateway, leading to the unknown.
Aizen's lone eye narrowed. He extended his senses, and an overwhelming vastness flooded his perception.
"The Senkaimon? No… this is something else."
A doorway beyond logic. A passage beyond worlds.
His lips curved into a smirk.
"Interesting."
Without hesitation, he allowed his consciousness to be pulled into the light—disappearing from Muken, and stepping into a new world.