"What is this?"
Naraku Sora examined the round object resting in the palm of his hand, a question mark practically appearing on his face.
*'You two worked so hard forging a sword for so long, and all you have to show for it is an iron rod?'*
"Actually, there was a slight deviation during the forging process," Urahara Kisuke explained with an awkward laugh. "The raw material for forging an Asauchi is the soul of a Soul Reaper. Because of this, we had to choose a substitute material with similar properties."
"After some investigation, we finally settled on the Reishi within the great underground prison."
"Unlike the rest of the Seireitei, this place serves as a boundary for imprisoning criminals, so there is no shortage of Soul Reapers who have died from various accidents."
"Because the outer layer of the prison is made of Sekki-seki, which effectively isolates all spiritual power, the underground prison is filled with Reishi mixed with souls."
"Mr. Mayuri thought that rather than leaving them to wander underground, it would be better to put them to good use as raw materials for forging a Zanpakutō."
"After developing the equipment to collect Reishi, we put it into action immediately."
At this point, Kurotsuchi Mayuri's expression suddenly turned somewhat irritated.
"The Reishi had been gathered in a confined area for a long time, so some subtle changes occurred in its properties, which ultimately led to the failure of the forging."
"If we had used the souls of Soul Reapers to forge it, there definitely wouldn't have been any problems."
Hearing this, Urahara Kisuke couldn't help but reach up and rub his brow.
"Mr. Mayuri, you're being a bit too extreme."
Naraku Sora looked thoughtful.
*'To sum it up, these two 'masterminds' collected the fragmented souls of criminals who died in the prison to use as raw forging materials, and then forged a Zanpakutō that doesn't look like a sword at all.'*
"It's no big deal if the research failed, right?" Naraku Sora shook his head dismissively. "Just start over. As for souls and whatnot, aren't there still plenty of stubborn nobles around?"
Urahara Kisuke: "?"
He had always felt that he was a standout among rebels, but compared to the two people in front of him, he was practically a model citizen.
However, on second thought, it didn't seem entirely unreasonable.
*'Sacrifices are inevitable in experimental research. If the nobles knew that their dedication could bring change to the Soul Society, they would surely be gratified, right?'*
The moment this thought popped up, Urahara Kisuke shook his head repeatedly.
*'I've spent too much time with these two guys, and it's making my own thoughts extreme.'*
*'The nobles are at the very top of the Soul Society's order. If they were gone, things would become very troublesome.'*
"Lord Naraku, now is not the time to discuss that issue. We will figure out a way to get the materials." Urahara Kisuke rubbed his face vigorously to make his expression look serious, preventing himself from being led astray by a certain someone again.
"The key is that iron rod in your hand."
"Because of the materials used, there's no problem considering it a part of the underground prison, which also gives it a special function."
"What is it?"
"It can open the lowest level, [Muken]."
Hearing this, Naraku Sora's eyes lit up.
He immediately reached out and patted Urahara Kisuke heavily on the shoulder. The exaggerated force made the man wince and bare his teeth.
"Well done, Kisuke! As expected of someone I value!"
"This Prison Warden grants you half a day—uh, two hours of leave. Go relax a bit."
Urahara Kisuke: "..."
*'You really are merciful.'*
After speaking, Naraku Sora took the iron rod and prepared to leave. However, just as he turned around, Urahara Kisuke grabbed him.
He spoke with a serious face, "Lord Naraku, the criminals imprisoned in Muken are all unforgivable thugs. You absolutely must not let them out."
Naraku Sora grinned, revealing a somewhat dangerous smile.
"Who said I was going to let them out?"
Seeing this expression, Urahara Kisuke shuddered.
*'Looks like someone is going to be out of luck.'*
In this regard, he could attest to having extremely rich experience.
After some persuasion, Urahara Kisuke gave up on this futile endeavor and instead went to prepare some things that might be needed in Muken.
Kurotsuchi Mayuri, on the other hand, brought out the surveillance bacteria he had recently developed.
As long as it was attached to an object or skin, it could achieve Reishi synchronization, observe the outside world, and store visual information.
Naraku Sora couldn't quite understand this. How could something as small as bacteria accomplish surveillance work?
After thinking about it carefully, he suddenly realized that Kurotsuchi Mayuri, who claimed to be a scientist, was actually the most unscientific guy of all.
To use his words—
*'How could Reishi be such an inconvenient thing?'*
Urahara Kisuke deeply agreed.
After simply bringing along a reinforced Denreishinki, the group of three set off toward the lowest level of the great underground prison.
After avoiding others, they quickly arrived at the entrance.
To prevent any accidents, Kurotsuchi Mayuri was responsible for guarding the entrance to the seventh level, while Urahara Kisuke was in charge of opening the entrance to Muken.
Because the eighth level and the upper seven levels were not a single entity, and coupled with the fact that the three of them were trespassing, the preparation work was somewhat tedious.
Before long, as Urahara Kisuke injected his Kidō Reiatsu, the space ahead began to distort, forming a pitch-black vortex.
After briefly sensing it to ensure there was no danger, he nodded to the person beside him.
"Lord Naraku, you can prepare to enter. Just in case, you must remember our agreed-upon secret signal. Also, releasing criminals without authorization is illegal..."
Before he could finish, Naraku Sora said with an impatient look, "Kisuke, how did you become as nagging as Old Man Yama?"
"I know what I'm doing!"
With that, he stepped forward, his body plunging straight into the constantly fluctuating vortex.
What greeted his eyes was endless darkness, as if it were a world where light did not exist.
He briefly released his Reiatsu to sense his surroundings.
Naraku Sora was astonished to find that no matter how much he expanded his Reiatsu range, he couldn't touch the edges of Muken. In terms of sheer area, it even surpassed the entire Seireitei.
It seemed to completely negate the concept of "space."
Naraku Sora extended a finger and released a Shakkahō with a faint amount of spiritual power, letting it hover near his body to act as a light source.
As the most commonly used Kidō among Soul Reapers, Shakkahō had a wide range of uses, and acting as a lighting tool like this was one of them.
Soon, the darkness slowly lit up.
Within the light, only the black, special-material floor could be seen. It didn't illuminate a ceiling or any walls, and the areas beyond the light were still enveloped in heavy darkness.
Next was the main event.
The criminals in the upper seven levels of the prison could no longer provide any effective benefits. Hopefully, Muken, which held the most vicious people in the Soul Society, could bring a little surprise.
According to the records kept in Shino Prison, there were quite a few criminals in Muken.
Most of them had an extremely high danger level and had committed felonies that Central 46 and even the entire Soul Society could not tolerate.
But because their Reiatsu reached the third-class standard, it was inconvenient to execute them, so they could only be imprisoned in Muken.
He just didn't know if these guys still possessed their former strength after being locked up for so many years.
If they were too weak, they would be of no value.
In that case, he might as well take them up and throw them to Aizen to be used as materials.
Walking forward along the pitch-black floor, he soon discovered an anomaly at the edge of the light source.
A smooth stone pillar.
On the floor made of Sekki-seki, there were some broken restraint belts and iron chains scattered about. It looked as if the criminal imprisoned here had escaped.
Naraku Sora curled his lips in disdain.
"Old Man Yama is still being stingy and refusing to give me the key. If we don't come down here to check, Muken is going to turn into a sieve."
However, just as he finished speaking, a faint fluctuation of Reiatsu suddenly came from the air, and a strong wind quickly swept past from the pitch-black darkness.
It was as if some unknown creature was walking quietly.
Naraku Sora frowned and subconsciously released his Pesquisa. An imperceptible gleam of light dissipated from his fingertips, instantly covering a radius of a thousand meters.
In a place like this where the concept of space was tampered with, Pesquisa was undoubtedly much more useful than a Soul Reaper's Reiatsu perception.
Soon, he discovered the source of the unfamiliar Reiatsu.
A man hiding in the darkness.
Emaciated and with disheveled hair, his face was full of hysterical madness. A pair of crimson eyes stared fixedly at Naraku Sora, as if treating him as his only hope.
Perhaps staying in Muken for so long had allowed him to remain unaffected by the dark environment.
It looked like he was preparing to hide in the shadows and ambush him, thereby gaining a chance to leave Muken.
If it were any other Soul Reaper, he might have actually succeeded.
Unfortunately, he had run into an absolute monster.
Naraku Sora grinned and, full of anticipation, followed the man's expectations, walking forward along the path until he entered the attack range.
Right then, an imperceptible click sounded.
An extremely violent Reiatsu suddenly burst forth, pouring down like a breached dam. The moment it instantly covered Naraku Sora, the man violently lunged out from the darkness.
His ferocious gaze met a half-smiling expression.
Kuroda Ryōsuke's heart suddenly skipped a beat.
*'Did this guy know I was here all along?'*
*'Then why was he pretending to be oblivious? Entrapment?'*
Kuroda Ryōsuke couldn't help but feel a bit panicked, but at this point, there was no room for regret.
As the third-generation Captain of Squad 10, even though he had been suppressed by Muken for hundreds of years, there was no way he could lose to a mere brat who didn't even have a Captain's haori.
Wrapped in violent Reiatsu, Kuroda Ryōsuke raised his arm. His emaciated body suddenly expanded, and powerful strength filled his arm, bringing with it a howling gale.
He threw a punch.
*Smack!*
A dull collision echoed in the empty darkness. The light of the Shakkahō reflected off a set of bared, gleaming white teeth, illuminating a hair-raising smile.
"With this level of skill, you're trying to pull off a prison break?"
Amidst a scalp-numbing sound of shattering bones, Kuroda Ryōsuke let out a tragic wail, bringing a trace of life to the long-silent Muken.
After casually crushing him, Naraku Sora looked toward the darkness ahead.
"Friend over there, how long are you going to keep watching?"