The other captains listened closely as Soi Fon laid out the intelligence, their expressions growing increasingly serious.
Aizen showed no visible reaction, but the more he heard, the more certain he became that the changes in Hueco Mundo were almost certainly connected to Cyrus.
"So we may be dealing with a Menos that has awakened some unusually powerful ability?"
Kuchiki Byakuya offered his guess once Soi Fon finished.
"That's only speculation."
Soi Fon shook her head.
"We don't maintain many observers inside Hueco Mundo. It's too dangerous to keep large numbers of Shinigami stationed there."
Seireitei had never stopped monitoring Hueco Mundo entirely.
Menos attacks on both the World of the Living and Soul Society were hardly uncommon, so naturally the Gotei 13 could not simply ignore an entire realm filled with Hollows.
That was why the enormous forest had been noticed so quickly. Soon after it appeared, the Hollows throughout Hueco Mundo began behaving abnormally.
The Shinigami assigned to observe the realm investigated as much as they could, realized that the situation might be serious, and immediately sent word back.
"If the reports are accurate, then quite a few powerful Hollows must have gathered around that forest by now."
Ichimaru Gin spoke with his usual narrow-eyed smile, looking irritatingly cheerful about the whole thing.
As he did, he casually glanced toward Aizen.
After all, the two of them were probably the only people present who had any idea what was really happening.
"Which is why the Captain-Commander ordered us to form a special expeditionary unit."
Soi Fon folded her arms.
"A large-scale invasion of Hueco Mundo isn't realistic."
As captain of the Second Division, Soi Fon had seen more than enough death to remain pragmatic about such matters.
A serious campaign into Hueco Mundo would inflict enormous casualties if they wanted any meaningful results.
Sending only captains wouldn't solve the problem either.
A handful of powerful individuals could accomplish a great deal, but not enough to purge a realm of this size.
Besides, Hollows could never truly be exterminated.
As long as people in the World of the Living continued dying while filled with hatred, resentment, and attachment, new Hollows would continue to appear.
"I have no objections."
Unohana Retsu smiled gently.
"I'll personally lead members of my division and bring several of our elites."
Soi Fon nodded, then looked toward the others.
Byakuya gave a silent nod of agreement.
Naturally, neither Gin nor Aizen intended to refuse. Both were interested in seeing exactly what had happened in Hueco Mundo.
Even Aizen hadn't expected the situation to change this dramatically in such a short period of time.
Then again, when he remembered the sheer power he had sensed from Cyrus, perhaps he shouldn't have been surprised.
His plans for Hueco Mundo would clearly need major revisions.
He might even have to reconsider where certain research projects were conducted.
Aizen had no intention of allowing something so important to his long-term plans to become unstable simply because an unexpected variable had appeared.
As he considered that, his gaze drifted toward Byakuya.
Byakuya noticed.
He turned slightly, a questioning look flashing through his eyes, but Aizen merely responded with a pleasant smile.
"Then we move immediately."
Soi Fon rose.
"These changes in Hueco Mundo are recent. The sooner we investigate, the better our chances of understanding what caused them."
She turned and left.
Unohana followed.
Byakuya also rose to depart, only to pause after taking a few steps.
"Captain Aizen. Was there something you wished to say earlier?"
"Nothing important."
Aizen smiled.
"I merely heard that among this year's graduates, there is someone with a connection to Captain Kuchiki."
Byakuya paused, then frowned before leaving without another word.
Gin glanced toward Aizen, his foxlike smile unchanged.
"Captain Aizen, you probably shouldn't phrase it like that in the future. Captain Kuchiki certainly isn't the type to show favoritism."
With that parting remark, Gin walked away as well.
Aizen sighed, looking mildly helpless, as though his earlier comment really had been nothing more than an innocent question.
Before long, all five captains had left.
…
Elsewhere, someone stood before Captain-Commander Yamamoto.
"How did the investigation go?"
Yamamoto rested both hands on his cane and asked calmly.
"Captain-Commander, that sort of work is hardly my usual responsibility."
The speaker was a woman. As she talked, her body swayed gently, almost as though she were floating rather than standing.
"This matter is important."
Yamamoto's long white beard shifted slightly, betraying just a hint of exasperation.
"What happened before was no accident."
"All right, all right. You were correct about that."
The woman relented.
"But whoever did it cleaned up extremely well. I couldn't find any useful traces."
Yamamoto seemed unsurprised.
"I understand."
"Then I'll take my leave. I do have plenty of responsibilities of my own."
She turned away.
Several skeletal arms hidden behind her back moved in a steady rhythm as she drifted out of the room.
"So that is how it is."
Yamamoto spoke quietly to himself.
"It seems Soul Society is about to become restless again."
There was little emotion in his voice.
Over the centuries, Soul Society had endured countless crises.
In the end, every one of them had been dealt with.
Soul Society remained Soul Society.
And if some fool truly appeared who refused to understand their place…
He could simply burn them away!
…
No one knew about the Captain-Commander's private investigation, but the five captains moved quickly.
After only a short period of preparation, the special expeditionary unit was assembled.
A passage into Hueco Mundo was opened, and the entire force entered.
Aizen walked near the rear with members of the Fifth Division, faint curiosity hidden behind his glasses.
He genuinely wanted to see what Cyrus had created there.
Once the expedition entered Hueco Mundo, a Shinigami was already waiting to receive them.
"Captain!"
The man belonged to the Second Division and immediately approached Soi Fon.
"The forest has stopped expanding. It's enormous and incredibly lush—completely different from the Forest of Menos. If the Forest of Menos feels like death itself, this place is overflowing with life."
He continued excitedly.
"If I didn't already know we were in Hueco Mundo, I'd think someone had dropped an entire forest from the World of the Living in here."
The man was clearly talkative, and his explanation quickly became a rambling monologue.
Still, the group managed to extract the important details.
"Specifics."
Soi Fon finally raised a hand and cut him off once he began drifting too far from the point.
"Huh? Oh—right, Captain."
The Shinigami scratched his head awkwardly.
"Something inside that forest seems to be attracting Hollows. Ordinary Hollows, Menos Grande, and even more advanced Menos have all been moving toward it."
He hesitated.
"Though it could also be the other way around. There are so many Hollows gathered there now that they might simply be attracting even more of their kind."
Under Soi Fon's stare, he wisely stopped before he could start rambling again.
"Lead the way."
Soi Fon gestured forward.
"We'll enter the forest and determine what's happening as quickly as possible."
"Captain, we should still be careful."
The Shinigami hurriedly added a warning.
"Several Vasto Lorde-class Menos appear to be heading there as well."
Everyone except Aizen and Gin reacted immediately.
Vasto Lorde were the highest class of Menos in Hueco Mundo.
Each possessed power comparable to a captain-class Shinigami, and some were believed to exceed even that level.
These were not enemies anyone could treat lightly.
It seemed this expedition was going to be far more dangerous than they had initially expected.