The moment the doors were pushed open, he was greeted by warm sunlight that shouldn't exist in Hueco Mundo.
The sun hung at the zenith, freely radiating light and heat.
Buildings of various styles were scattered across the flat ground, looking remarkably like the Shino Prison after its several reconstructions.
Lush greenery lined both sides of the bustling roads, with a faint fragrance permeating the air.
Looking at the scene before him, Yamamoto's expression was somewhat peculiar.
Just as Naraku Sora had said when inviting him to Hueco Mundo, perhaps because he had visited the Shino Prison barracks so many times, coming here truly gave him a sense of returning home.
If one ignored the Menos Grande coming and going on the streets, the environment here was actually quite suitable for retirement.
Yamamoto kept this thought to himself and followed Naraku Sora down the street.
Most of the figures on the road wore white uniforms and were busy with their respective tasks. Even when they encountered Naraku Sora, they merely bowed respectfully, greeted him, and hurried away.
As for Yamamoto, they only cast a curious glance or two at him.
In Las Noches, especially around the King, nothing was surprising.
It was just a Soul Reaper, after all. It wasn't the first or second time.
Previously, the King had brought back a powerful female Soul Reaper and stayed in his chambers with her for days and nights without coming out.
After coming out, that woman had even given General Grimmjow a severe beating.
The Vasto Lorde Arrancar who had fought all across Las Noches were actually completely defenseless against that female Soul Reaper.
Having seen so much, the Arrancar were no longer as interested in strange occurrences.
Leading Yamamoto, Naraku Sora walked into a palace.
The interior was spacious and bright, and quite a few people were already waiting quietly. Almost all of them were Arrancar.
Yamamoto narrowed his eyes, sensing the immense strength of these Arrancar.
Two of them, in particular, forced him to brace himself.
One looked lazy and sluggish, with short, slightly curly brown hair, leaning back in his chair as if he were about to fall asleep.
Strangely, the Reiatsu emanating from him gave Yamamoto a sense of incompleteness.
The other was somewhat familiar—a robust old man with graying hair and a beard, currently engrossed in flipping through a newly serialized book.
Looking at the cover, it seemed to be *The Rose-Colored Path*, written by his other rebellious disciple.
Yamamoto: "..."
*Do Menos Grande also enjoy reading romance novels?*
The scene before him was completely different from the solemn and oppressive atmosphere he had imagined.
The Arrancar were doing as they pleased, as if this were just an ordinary gathering.
It was incredibly similar to how Soul Reapers interacted in the Seireitei.
In Yamamoto's understanding, Hollows were inherently hostile creatures. Driven by their instinct to evolve, they often resorted to any means necessary.
But here, he saw not the slightest hint of tension, nor any trace of greed toward their peers.
This relaxed way of interacting made Yamamoto wonder—*Is this really still Hueco Mundo?*
Furthermore, in his perception, aside from the two who required special attention, the other Arrancar were not far behind.
Just the Reiatsu they unconsciously released gave off an intense sense of oppression.
An ordinary Soul Reaper Captain would absolutely not be their match.
*To think that rebellious disciple secretly cultivated so many high-level combatants, and I, as the Head Captain, was completely unaware.*
*If this group of Arrancar were to launch a surprise attack on the Soul Society, wouldn't they be able to strike straight at Squad 1 and force me to step down?*
Yamamoto took a deep breath.
He suddenly felt a bit more anticipation for what might happen in the future.
Just as he was pondering the likelihood of such a development, the others also noticed the white-bearded old man following their King.
A sudden chill ran down everyone's spines.
The seemingly ordinary old man gave off the aura of a walking natural disaster.
Even from a distance, they could still feel an uncontrollable, scorching heat, as if they were standing in the middle of a volcano.
*Just who is this old man?!*
While everyone began to speculate, Urahara Kisuke, who was hiding in the back playing chess with Szayelaporro, was already wiping away cold sweat.
Just because the Arrancar didn't recognize this white-bearded old man didn't mean he didn't.
*Speaking of which, why is the Head Captain here?*
*Could it be that Head Captain Yamamoto has seen through Naraku Sora's wild ambitions and is preparing to execute this traitor right here and now?*
At this thought, Urahara Kisuke's eyes lit up.
Just as he was envisioning a beautiful future, Yamamoto clearly noticed this pillar of the Soul Society, the genius scientist who had made outstanding contributions.
His face instantly darkened.
*I thought I was the first to know about Naraku Sora stirring up trouble in Hueco Mundo, but to think someone else beat me to it.*
*Is this Urahara Kisuke really more trustworthy than me?*
Sensing Yamamoto's unfriendly gaze, Urahara Kisuke froze for a moment, forcing an awkward smile onto his face.
As the two groups observed each other, a figure stepped forward.
Seeing this person, Yamamoto's expression faltered slightly as he recognized his identity.
The Lieutenant of Squad 5, Naraku Sora's close friend, and another talent skilled in science—Aizen Sōsuke.
"Head Captain Yamamoto."
Yamamoto narrowed his eyes slightly, staring intently at Aizen.
Although the other party wasn't releasing any Reiatsu, his intuition told him that the young man before him was absolutely not simple.
Powerful, exceptionally capable, yet never showing off in front of outsiders—someone who could do this was no ordinary person.
Even when facing him, the Head Captain, he remained neither haughty nor humble, acting calm and unhurried, as if everything was under his control.
Yamamoto suddenly had a strong intuition that a significant portion of the credit for his rebellious disciple reaching this point today was inextricably linked to this Aizen.
Thinking of this, he felt somewhat emotional.
*Without realizing it, that rebellious disciple has gathered a group of reliable people around him.*
*Back in the day, I relied on invincible martial prowess to forcefully gather the original Gotei 13 together.*
*This moment is just like that moment.*
*In another hundred years, the Soul Society might very well reach new heights under Naraku Sora's leadership.*
Yamamoto let out a long breath, no longer feeling the slightest bit of worry about the upcoming experiment.
"What do I need to do next?"
"Get on the operating table?"
Hearing this, Aizen was actually taken aback. He hadn't expected Yamamoto to be so calm, lacking even the slightest bit of expected nervousness.
Seeming to see through Aizen's current thoughts, Yamamoto's gaze remained calm as he spoke in a deep voice,
"Since I have made a choice, I will firmly see it through to the end. Indecision is not in my nature."
Aizen nodded. "I understand."
Next, he detailed the Hollowfication experiment.
After multiple trials, coupled with the collection of Spirit King fragments, the success rate of Hollowfication had already reached over ninety percent.
However, there was still one problem that could not be overcome.
That was, during the Hollowfication process, the subject would fall into an unconscious state and act entirely on instinct.
It was fine for other Soul Reapers; they could be controlled by casually casting a few Kidō or applying some restraining measures.
But Yamamoto was different.
As the existence known as the strongest Soul Reaper, the only one capable of facing him head-on across both the Soul Society and Hueco Mundo was Naraku Sora.
Yamamoto expressed his understanding of this.
Although he didn't say it aloud, he still highly acknowledged his foolish disciple's strength.
"Beating up my rebellious disciple? Then I shall look forward to it."
Yamamoto grinned, revealing a smile that sent chills down the spines of all the Arrancar.
In the barren desert thousands of kilometers away from Las Noches.
The top combatants of Las Noches were all gathered here.
When they learned that the subject of the upcoming Hollowfication was Yamamoto Shigekuni, who had guarded the Soul Society for a thousand years, their expressions grew increasingly solemn.
Last time, when Aizen underwent Hollowfication, he nearly wiped out their entire group of Espada.
If Naraku Sora hadn't stepped in to control the situation, every single one of them present wouldn't have been able to escape.
This time, the subject of Hollowfication was replaced by the Head Captain of the Gotei 13, Yamamoto Shigekuni.
One had to remember, as strong as Aizen was, he was still only a Lieutenant!
While they were mentally preparing themselves, Aizen was earnestly giving instructions on the side.
"The principle of Hollowfication is actually very simple."
"When Hollowfication begins, you will see the 'Hollowfied self' in your inner world. All you need to do is defeat them to master the power of Hollowfication."
"It is worth noting that during the Hollowfication process, you might see some scenes that exist in your subconscious. Remember not to be affected by them."
"Just treat them as illusions."
"..."
"The Hollowfication experiment is not without the possibility of failure, but after so many years of our hard work, we have reduced the side effects of failure to a minimum."
"Even if it fails, it just means you will never have the chance to master this power again."
Hearing this, Yamamoto frowned. "Didn't you say that if Hollowfication fails, it will lead to Soul Suicide?"
Aizen glanced faintly at Naraku Sora beside him and calmly explained,
"That was the technology from several versions ago."
"A certain someone is ignorant and incompetent, so naturally, he wouldn't know these things."
Yamamoto took a deep breath and immediately glared fiercely at his rebellious disciple.
Naraku Sora: "..."
*Why is he tattling to the parents?*
*He isn't a researcher, so isn't it perfectly normal for him not to understand these things?*
While the few of them were conversing, Urahara Kisuke had already adjusted the equipment. After inserting the Hōgyoku, he gave Aizen an 'OK' gesture.
When everyone was ready, a blue-purple ray resembling a pillar of light shot out and landed on Yamamoto.
A suffocating Reiatsu surged down, immediately causing Yamamoto's head to droop as if he had fallen asleep. The surroundings instantly fell silent.
The Espada tightly gripped their respective blades, staring fixedly at the old man sitting cross-legged on the silver sand, standing in strict formation.
The next second.
A surging, blood-red Reiatsu transformed into a massive pillar of light that shot into the sky. A brutal and tyrannical aura suddenly spread out, accompanied by the continuous, scalp-numbing sound of shattering.
The air let out overwhelmed explosive pops as the moisture within it began to evaporate.
The temperature rose steadily, instantly dispelling the cold of Hueco Mundo.
"Prioritize ranged suppression to consume Head Captain Yamamoto's Reiatsu and stamina."
Aizen's calm voice rang out, acting like a stabilizing anchor that steadied the Arrancar's uneasy mindsets.
"There is no need to worry. Sora is here."
As soon as he finished speaking, the massive pillar of light completely retracted, sinking into Yamamoto's body, and a terrifying, scorching wind was whipped up.
When he raised his head, everyone subconsciously held their breath.
His originally aged face was covered by a ferocious bone mask. His golden, slit-like pupils were filled with icy coldness as his gaze swept over the crowd.
As if sizing up prey...