Aizen's Hollow mask actually bore some resemblance to the image in his memory.
The pure white mask lacked any superfluous decorations; there was only a single crack running from the forehead down to the chin, making it look like a pupa about to break out of its cocoon.
Most importantly, his usual calm demeanor had vanished, replaced by the negative emotions characteristic of a Hollow.
Naraku Sora stepped back, clearing a massive open space.
As the chief director of this experiment, Urahara Kisuke immediately stepped up to the front.
"Everyone, prepare for battle."
"During his Hollowfication, Lord Aizen's mind will be completely immersed in his inner world as he defeats the Hollow within."
"Meanwhile, his physical body left in the outside world will be driven by instinct, launching indiscriminate attacks against everything in sight."
"Until Lord Aizen successfully masters his Hollowfication, we must suppress him as much as possible and drain his power to prevent him from completely losing his sanity."
At this moment, both the Arrancars and the Soul Reapers wore solemn expressions, standing in strict formation.
The Arrancars' gratitude toward Aizen was no less than their gratitude toward Naraku Sora.
They were well aware of Aizen's contributions to Las Noches, so they would not take a single step back no matter what.
As for the Soul Reapers, they were merely familiar with Aizen.
They knew he was Lord Naraku's close friend.
Out of their trust in Naraku Sora, they would also go all out.
Aizen stood rooted to the spot, seemingly unlike other Hollowfied Soul Reapers who were instantly driven by instinct.
Urahara Kisuke frowned, feeling that the situation was slightly different from what he had anticipated.
Just as he was about to continue issuing orders, those tightly shut eyes slowly opened, and a flash of extreme brutality gleamed within the golden pupils.
"Hadō #63・Raikōhō."
Kurotsuchi Mayuri, who had been observing Aizen all along, was the first to launch a probing attack.
A dazzling golden thunderbolt tore through the night sky and crashed fiercely toward Aizen's position. In an instant, a massive surge of electrical arcs erupted, completely engulfing him.
Urahara Kisuke instinctively glanced at Kurotsuchi Mayuri beside him, a hint of surprise appearing on his face. After all, as a fellow Kidō genius, judging a Soul Reaper's Kidō proficiency was effortless.
With just a single glance, he could tell that Mayuri's mastery over Raikōhō had reached a level of perfection.
To think that Mayuri, who was constantly immersed in scientific research all year round, hadn't let his Kidō skills fall behind in the slightest.
Yet even so, it still failed to inflict any effective damage on Aizen.
The leaping golden lightning was effortlessly blocked by a single hand. The dissipating electrical arcs blasted deep craters into the ground, and the few that occasionally landed on his body left absolutely no marks behind.
Seeming somewhat puzzled by his current state, Naraku Sora actually caught a trace of confusion in those golden pupils.
*What does this mean?*
*Is this guy still able to think while in a Hollowfied state?!*
He suddenly felt a pang of pity for everyone about to face Aizen in battle.
Aizen's instincts might be quite different from what they understood them to be.
Clenching his five fingers together, Aizen snuffed out the Raikōhō with a sharp crack, sending plasma splattering in all directions.
Aizen tilted his head, quickly shifting his attention to Grimmjow, who was standing at the very front.
That recklessly erupting Reiatsu was like a lighthouse in the ocean, exceptionally eye-catching.
He took a step forward, producing a muffled thud.
Aizen vanished from his spot, as if traversing through space, and instantly appeared right in front of Grimmjow.
An arm covered in white chitin reached out. His five fingers spread open as Reiatsu gathered, forming a blade in an instant.
Grimmjow's eyes widened, and he drew his sword at top speed:
"Grind, Panther King..."
Before he could even finish his sentence, that Reishi longsword struck out like a heavy hammer. Terrifying power poured entirely into his body, directly interrupting his nearly completed Resurrección.
Without even having the time to let out a scream, an explosive boom erupted. Dragging a long wake behind him, his entire body instantly vanished from sight into the distance.
Seeing this scene, Naraku Sora's eyes lit up.
Setting Yamamoto and Ichibē Hyōsube aside, the current Aizen was absolutely the strongest person he had ever seen.
Even Kuruyashiki Kenpachi, who had nearly destroyed the Seireitei back then, was far inferior.
That guy had merely relied on the mechanics of his Zanpakutō and the buffs from Hell.
In contrast, because Aizen lacked his sanity, his Zanpakutō, Kyōka Suigetsu, couldn't be utilized; he could only rely on pure, raw stats.
His already exaggerated Reiatsu, amplified by Hollowfication, erupted into the most terrifying spectacle.
"Roar, Tenken!"
Komamura Sajin took a step forward, being the first to recover from the shock. Without any hesitation, he directly activated his Shikai to stall for time.
A gigantic blade materialized out of thin air, cleaving straight down toward Aizen.
Compared to the grandiose Bankai, the Shikai lacked a bit in power, but it made up for it by being swift and concealed, focusing entirely on catching the enemy off guard.
A fierce wind suddenly kicked up, swirling countless grains of silver sand.
*Boom!!*
Aizen didn't even bother to dodge. He simply stood in place and raised his right hand, his slender blade pressing perfectly against Tenken.
Komamura Sajin's proud strength couldn't even force him to take half a step back.
"Shoot to kill, Shinsō."
A calm voice rang out from behind Komamura Sajin, and an imperceptible glint of blue light flashed through Ichimaru Gin's eyes.
At the exact moment of its release.
A dazzling white light streaked across the silver sand, filling the air with intense heat generated by high-speed friction.
*Clang—*
He didn't hold back in the slightest. It wasn't until the fierce blade was about to touch Aizen that the ringing of the sword finally arrived.
Under everyone's watchful eyes, the blade's gleam landed violently on Aizen's body, only to burst into a series of sparks.
Followed by an ear-piercing screech of friction.
Relying solely on his Shikai at this stage, Ichimaru Gin was not strong enough to break through Aizen's defenses.
But his goal had already been achieved.
A dangerous thing like Bankai was not suitable to be used on Lord Naraku's friend. His role in this battle was merely to run interference.
He would leave the frontal assault to the others.
"Bankai—"
"Kokujō Tengen Myō'ō!"
Taking advantage of the brief window where Aizen was distracted, Komamura Sajin completed his Bankai at top speed. A black-armored samurai, hundreds of meters tall, appeared on the wasteland, instantly forming a massive sand pit beneath its feet.
Howling winds roared as a terrifying blade, tens of meters long, was abruptly drawn from its sheath and cleaved vertically downward.
Wherever it passed, a loud noise akin to tearing fabric echoed out, and visible air currents parted to both sides.
The sheer scale of the attack was massive, its destructive power increased by more than tenfold compared to his Shikai.
Seemingly sensing that this strike might pose a threat to him, Aizen's gaze instantly locked onto Komamura Sajin, who was controlling Kokujō Tengen Myō'ō.
Thus, he raised his left hand.
Urahara Kisuke, who had been observing all along, felt his pupils shrink. Just as he was about to open his mouth to issue a warning.
An overlapping voice, sounding like resonating metal, suddenly rang out.
"Hadō #90・Kurohitsugi."
The moment the words fell, black Reiatsu surged up from the ground. The turbulent torrent expanded layer by layer, like stacking data, and instantly enveloped Komamura Sajin.
A massive black coffin, over ten meters tall, stood like a fortress wall upon the wasteland.
In the next second, the torrent receded, revealing Komamura Sajin's figure.
His tall, burly body was covered in slash marks. Blood splattered wildly, directly dyeing him into a red dog.
Looking at the fallen Komamura Sajin, Naraku Sora couldn't help but twitch his eye.
*What is the meaning of this?*
*Even when driven purely by instinct, he can still use Kidō?*
*Just how much do you love Kurohitsugi, Aizen, to turn this thing into an instinct?*
While he was pondering this, the battle erupted once more.
This time, the main attackers were the Espada.
Thanks to Komamura Sajin's interference, they had instantly completed their Resurrección, adopting their strongest forms to confront the man they viewed as Hueco Mundo's scientist.
"Say, didn't Lord Aizen mention that he was just a scientist and didn't possess power like His Majesty Naraku?"
Lilynette scratched her head. "But why do I feel like he's still as strong as a freak?"
Tier Harribel fired off a Trident Mist Halberd backhandedly to check Aizen's Sonído, explaining without even turning her head:
"How could someone who became friends with His Majesty possibly be a weakling!"
Looks of sudden realization appeared on the others' faces.
Explained like that, it made perfect sense.
While the few of them were conversing, the moonlight and stars in the night sky were obscured by thick, heavy clouds, and the Reishi density in the air skyrocketed drastically.
When the first drop of freezing rain, condensed from high-density Reishi, fell from the clouds, everyone felt as if they could hear the earth trembling.
The wind began to pick up.
The Reiatsu settled, surging massively yet slowly like flowing mercury. But as a hurricane whipped up, a sandstorm capable of sweeping away everything began to brew in the wasteland.
The silvery-white sand danced madly, blotting out the sky and the sun.
Gazing at the apocalyptic scene that had suddenly appeared due to the eruption of Reiatsu, the expressions on everyone's faces instantly froze. A fear originating from the deepest depths of their instincts welled up in their pupils.
This was the spontaneous fear born when lesser beings faced a higher existence.
Fortunately, whether they were Arrancars or Soul Reapers, they were all individuals with resolute wills, perfectly capable of overcoming it on their own.
Feeling the heavy Reiatsu permeating the air, Naraku Sora raised an eyebrow and began to stretch his body, preparing himself for battle.
He had been wanting to beat up Aizen for a long time now.
If he hadn't taken into account the need to train his troops, he would have already made his move the moment the Hollowfication began.
"Kisuke, how much longer do you think they can hold out?"
Urahara Kisuke watched the crowd charging at Aizen one after another, his eye twitching:
"Lord Aizen's Hollowfication intensity has exceeded our original estimates."
"Judging solely by his performance, perhaps only Lilynette can stall him slightly; everyone else is destined to be instantly killed."
Just as his voice fell, Nnoitra had one of his arms directly sliced off by Aizen.
Blood flew through the air under the moonlight, possessing a bizarre sense of beauty.
At this very moment, Aizen was already completely covered in white. The chitinous shell, which should have resembled armor, fluttered in the wind under the influence of his Reiatsu.
Almost no one could stop his advancing footsteps; wherever he passed, there were only figures crashing to the ground.
Watching the white figure weaving through the crowd, Naraku Sora's face was written with anticipation. Reiatsu surged wildly around him, forming twisted lines in the air.