A biting, icy wind poured out endlessly from the opened gateway.
In an instant, the temperature inside the First Division headquarters plummeted. Even the dense spiritual pressure of the captains present could not completely block the frigid chill flowing out from the other side.
Through the distorted boundary of the gateway, one could vaguely see the world beyond
A vast, pale land buried beneath endless ice and snow.
Jūshirō Ukitake had not previously realized that the device Urahara Kisuke had been constructing with such care was, in fact, a specially modified Senkaimon, designed to forcibly connect to an unknown Reishi-based subspace.
However, what he could not understand was the Captain-Commander's true intent.
Surely, Yamamoto had not gathered them here merely to observe a gateway being opened.
"Captain-Commander," Ukitake asked softly,
"what exactly is this place?"
Kyōraku Shunsui also turned his gaze toward Yamamoto, his usual relaxed expression gone.
Although Unohana Retsu said nothing, her attention was completely focused, ready to grasp every detail of the answer.
Yamamoto replied calmly,
"Captain Gosuke and the others will explain."
Kyōraku's eyes shifted toward Gosuke Shigure.
"Gosuke…" he said slowly.
Gosuke did not hesitate.
"This is a Reishi subspace concealed within the shadows of Seireitei."
He had no intention of hiding the truth.
"The shadows… of Seireitei?"
Ukitake's expression changed immediately.
Kyōraku's face also grew serious.
"Are you certain?" Kyōraku asked.
Gosuke looked back at him.
"What do you think?"
Kyōraku fell silent.
At that moment, he finally understood why Yamamoto had summoned so many captains at once.
If such a massive space truly existed beneath Seireitei itself—
It was no exaggeration to call it a catastrophe-level discovery.
A vast hidden world beneath the heart of Soul Society.
Was it natural?
Or was it artificially constructed?
Kyōraku and Ukitake instinctively reached the same conclusion.
It had to be artificial.
There was no possible way for such a perfectly structured space to form naturally within shadows.
Which led to the most unsettling question of all—
Who created it?
"We'll enter and confirm it ourselves,"
Yamamoto said, breaking the silence.
The captains nodded solemnly.
Yamamoto then turned his gaze toward Shihōin Yoruichi, Urahara Kisuke, and Kurotsuchi Mayuri.
"You three will remain here and guard the gateway."
"The rest will enter with me."
"Huh?"
Yoruichi immediately protested.
"Captain-Commander, we were the ones who discovered this place, and now you're telling me and Kisuke to stay behind? That's pretty unfair."
Yamamoto looked at her silently.
His gaze alone was enough.
Yoruichi immediately shut her mouth.
"…Tch."
After a moment, she muttered to herself,
"Well, someone has to hold the rear, I guess. Might as well be me."
Thus, Yoruichi remained behind with Urahara Kisuke and Kurotsuchi Mayuri.
Yamamoto led the others—
Kyōraku Shunsui, Unohana Retsu, Gosuke Shigure, and Jūshirō Ukitake
Through the gateway.
Although they had already glimpsed the scene beyond from outside, stepping into the subspace in person revealed its true scale.
The world was far more expansive than expected.
An endless frozen land stretched out before them, blanketed in snow and ice, suffused with an unnatural stillness.
The cold here was absolute.
Even spiritual bodies could not ignore it.
Jūshirō Ukitake, whose constitution had always been weak, shuddered involuntarily the moment he entered.
At that instant
Yamamoto drew his Zanpakutō.
"Reduce all things to ash…
Ryūjin Jakka."
Blazing flames erupted, coiling around the ancient blade.
The overwhelming heat surged outward, forcibly driving back the cold and stabilizing the environment around them.
Kyōraku couldn't help but whistle.
"Using Ryūjin Jakka just to deal with the temperature, huh?
Old man, that's overkill even for you."
The next moment, Kyōraku felt a piercing gaze land on him.
Yamamoto's voice was low and firm.
"This old man is preparing for battle."
"There is an enemy's presence…
within that palace."
Kyōraku stopped joking.
All eyes turned forward.
In the vast white world, a gigantic palace of ice and silver stood in the distance, dominating the frozen landscape.
Its design was sharp, rigid, and orderly—
completely unlike Shinigami architecture.
Any lingering doubt vanished instantly.
This place was man-made.
There was no possibility otherwise.
"Who would build something like this…
beneath Seireitei itself?" Kyōraku muttered.
He glanced at Gosuke Shigure.
"You know, don't you?"
Gosuke did not deny it.
"…The Quincy,"
he said quietly.
More precisely
"Their progenitor."
Kyōraku and Ukitake both stiffened.
Kyōraku opened his mouth as if to say something
But Gosuke had already drawn his Zanpakutō.
The meaning was unmistakable.
This was no longer a discussion.
It was a battlefield.
Unohana Retsu narrowed her eyes as she stared at the distant palace.
A familiar pressure lingered there.
A presence she had felt long ago.
So had Yamamoto.
That was why he had unsheathed Ryūjin Jakka without hesitation.
Yhwach.
The progenitor of the Quincy.
At that very moment
Inside the frozen palace, a young man with refined features slowly rose from his seat.
His calm expression finally grew solemn.
Without hesitation, he issued an order.
"All members… assemble."
A Quincy with a sharp gaze and vivid fuchsia mohawk scoffed.
"Hugo, did something happen?"
Around him, other Quincy elites turned their attention toward the young man.
Since His Majesty Yhwach had been defeated and fallen into dormancy nine hundred years ago, it was this man who had gathered the surviving Quincy and led them in constructing this shadow realm beneath Seireitei.
During the long centuries of Yhwach's slumber, he had acted as the de facto leader of the Quincy.
But
That did not mean all Quincy were willing to obey him.
After all
He was not the Emperor himself.
Many Quincy deeply resented the cautious, restrained path he had chosen.
For nine hundred years, the Quincy had lived in hiding, suppressed, watching their enemies flourish.
Their patience…
Was nearing its limit.