Based on Kisuke Urahara's understanding of Sōsuke Aizen—the man who included even random passersby in his schemes and arranged everything without a single leak—it was impossible for him to leave such a loophole.
Urahara had hoped that if Kai hadn't fallen under Kyōka Suigetsu, they might have had an extra trump card for victory.
But unfortunately, Aizen had considered this long ago.
Those under Kyōka Suigetsu's influence were helpless before Aizen.
Because Kyōka Suigetsu's ability is "Complete Hypnosis." It can make the target completely believe that a specific object's appearance, shape, mass, feel, and even scent are whatever the master desires.
As long as the opponent sees the moment of release once, their five senses and spiritual energy detection are completely hypnotized.
This is the true reason why Aizen lied about his Zanpakutō being a "running water" type that uses mist and irregular reflections to confuse enemies into infighting, and why he frequently demonstrated it to the Gotei 13 and the Shin'ō Academy.
It was precisely because of this that he, Yoruichi, and the others lost their ability to resist.
As expected, I hoped for too much.
Urahara couldn't help but shake his head in disappointment, only to see Kai suddenly smile and tap the table.
"But... Kyōka Suigetsu seems to be ineffective on me."
Kai spoke calmly, and for the first time, Urahara's expression changed drastically.
Yoruichi couldn't resist grabbing Kai's wrist. "What do you mean by that? If you've already fallen under Kyōka Suigetsu, why would it be nullified?"
"Could it be... you discovered Kyōka Suigetsu's weakness?"
A gleam flashed in Urahara's eyes as he asked in disbelief.
"I did discover a weakness, but Kyōka Suigetsu is ineffective on me not because I noticed a flaw."
Kai shook his head, speaking cryptically. "I am someone who has died once, after all."
What does the Kyōka Suigetsu on "Kuchiki Shinji" have to do with me, Kai?
Surprise! The person inside has changed, so of course, the hypnosis is invalid.
This was also the reason why, whenever Aizen visited the Academy over the years, Kai would find an excuse to slip away.
Only an idiot would get hypnotized a second time. Kai didn't know if his current "Hōgyoku Fusion Stage 1" state could tank Kyōka Suigetsu, so avoiding it was safer.
Clearly, Aizen didn't think too much of it.
In his eyes, Kai was someone who had already been hypnotized once and posed no threat. Aizen simply interpreted Kai's avoidance as a desire to stay away from him and refuse recruitment.
"Died... once? You mean when you were nearly killed by that Menos three years ago? I see."
Urahara seemed to realize something. But whatever he was imagining or brainstorming, as long as he didn't ask, it saved Kai the trouble of explaining.
"What about the weakness? What is Kyōka Suigetsu's weakness?"
Tessai couldn't help but ask anxiously.
As long as they grasped the method to break Kyōka Suigetsu, they would have the capital to counterattack instead of always being passive.
"Speaking of which, shouldn't you tell me why Aizen has been targeting you and hasn't given up searching for you all these years?"
Kai smiled and countered with a question, not revealing that he already knew about the Hōgyoku.
In fact, this was the best opportunity to formally get involved with the Hōgyoku in Urahara's possession.
Although he had already fused with one Hōgyoku and successfully started his evolution into the First Fusion Stage, Kai didn't know if the Hōgyoku inside him was perfect or flawed, or if it had side effects.
So, he needed the Hōgyoku in Urahara's hands as a backup.
"Since Yoruichi trusts you, there is naturally no need for me to doubt you anymore."
Seeing Yoruichi nod slightly to express her opinion, Urahara reached into his robe and took out a transparent crystal box.
Inside, a blue-purple gem lay quietly.
"This is the reason Aizen has been searching for me."
Urahara explained briefly.
But just then, the Hōgyoku suddenly began to vibrate. An invisible force began to spread, extending like tentacles, displaying an extremely high level of activity.
That wasn't all.
Urahara's face twisted in shock as he watched the Hōgyoku struggle within the seal, almost breaking out of the "box" to fly out.
"This is... 'Master Recognition'?"
"How is this possible?!"
In the hundred-plus years he had possessed the Hōgyoku, Urahara had never seen it in this state.
Even he, its creator, couldn't get the Hōgyoku to acknowledge him as its master.
But now, the Hōgyoku clearly showed a tendency to "recognize a master." It acknowledged someone's existence and showed a desire to fuse with them.
Urahara's eyes were filled with horror.
The people present were the same as always.
The Hōgyoku had never shown such a strong fusion tendency in his hands or around Yoruichi and Tessai.
Then the greatest possibility was... Kai?
The Hōgyoku acknowledged him?
But how is that possible?
The scene before him exceeded Urahara's expectations and imagination. This was something he had never anticipated.
"What is... this?"
Kai covered his chest inconspicuously.
At that moment, he also felt an intense longing.
It was the plea of his Hōgyoku.
The Hōgyoku fused with him was yearning to merge with the one in Urahara's hand.
Kai had a feeling.
If he could fuse with Urahara's Hōgyoku, his evolution speed would accelerate significantly, allowing him to step into higher fusion stages much faster.
This was a very strong premonition!
"What... terrifying talent and mental fortitude. To be acknowledged by the Hōgyoku in an instant... Kai-kun, you really gave me a huge surprise."
Urahara's shocked gaze gradually calmed. He steadied his breathing and placed the box containing the Hōgyoku on the table.
"As you can see, this gem contains a terrifying power sufficient to change the world. Its name is the Hōgyoku (Breakdown Sphere)."
"The Hōgyoku possesses a substance that can break the boundary between Soul Reapers and Hollows. It can help Soul Reapers undergo Hollowfication, or help Hollows become Arrancars and gain Soul Reaper powers."
"Aizen wants to obtain this power to break the boundary between Soul Reapers and Hollows, which is why he has been searching for us."
"The Hōgyoku is what he wants."