Meanwhile, Aizen's true body had arrived at his laboratory.
The one who had just spoken with Barragan, Gin Ichimaru, and the others was merely an illusion created by Aizen's Kyoka Suigetsu, using an Arrancar Gillian as its medium.
Aizen's laboratory was not even located in Las Noches, because he had quite a few secret research projects of his own.
Then, Aizen looked over everything in the laboratory, especially the experimental subjects he had just acquired—five Berserkers!
Naturally, Aizen was interested in Berserkers. Like Yoruichi Shihoin, aside from investigating Kisuke Urahara's soul foreign-matter extraction technique at the Great Spirit Book Corridor, Aizen had also taken the time to observe Berserkers.
After his battle with Ichigo Kurosaki, he had already realized that Berserkers were anything but ordinary.
The result was that Ichigo Kurosaki was not the sole exception. All Berserkers were like this.
For a researcher like Aizen, naturally, he had to thoroughly investigate the true nature of Berserkers.
He vaguely sensed that the key to whether he could obtain another Hogyoku might lie with the Berserkers.
"Can Berserkers become Hollows? Or rather, can Hollows become Berserkers?"
Countless ideas surfaced in Aizen's mind, and these were merely the most basic ones.
He even wanted to try and see what changes would occur if the Hogyoku absorbed a Berserker's soul.
For the time being, he was in no hurry to obtain Rukia Kuchiki's Hogyoku.
On one hand, it would not be easy. On the other, perhaps he would no longer need that Hogyoku.
From the Berserkers, Aizen saw the possibility of surpassing the limits of Soul Reapers and the limits of Hollows.
However, he was very cautious. There was no way he would so easily apply it to himself.
Thus, he planned to first test it on other Hollows or Soul Reapers.
"Just