It was also because the 13th Division's Shinigamis stationed around the living world suffered excessive casualties that Hollows ran rampant all over in many places.
And it was because of so many Hollows that the Quincy remnants hiding in the living world could no longer remain concealed as they started taking action to destroy Hollows.
When Shinigamis killed Hollows, their main goal was purifying the Hollows' souls. The souls of Hollows slain by Shinigamis could still reincarnate in the living world's cycle of rebirth.
But the Quincies' power of destruction came from the Soul King's original power of destruction used to annihilate ancient Hollows. It could completely destroy a Hollow's soul, dissolving it entirely in the world.
The Shinigamis of Soul Society might slack off about other matters, but when it concerned the balance of the world's existence — they stared at it unwaveringly.
The number of souls in the Shinigami world was fixed. At the same time, maintaining the souls of Soul Society, Hueco Mundo, and the living world in an extremely subtle equilibrium was necessary for the stability of all three realms.
Most human souls in the living world would enter Soul Society upon death while a minority degenerated into Hollows entering Hueco Mundo.
The Shinigamis of Soul Society played the role of protecting this stability of the worlds amidst this cycle.
When the number of Hollows in Hueco Mundo exceeded the balanced range, the Shinigamis would order the Hollow Hunting Forces stationed in Hueco Mundo to slaughter Hollows, sending some Hollow souls to reincarnate and maintain the three worlds' stability.
If the Hollow quantities in Hueco Mundo suddenly dropped drastically, the Shinigamis would also utilize certain methods to make a portion of Soul Society's souls disappear...
Of course, such secrets were things Ailin knew of from the memories of his previous life on the Blue Planet.
Even in Seireitei currently, the ones who could truly know of these secrets were probably limited to the Five Great Noble Families, Captain Commander Yamamoto, Shunsui Kyōraku, Jūshirō Ukitake, and several others.
The Quincies hidden in the living world killing Hollows meant those Hollow souls were directly destroyed without reincarnation or entering Soul Society, decreasing the total number of souls in the entire world. Such abnormality was quickly discovered by Soul Society as they locked onto the Quincy remnants of the Empire of Light.
The troops Yoruichi brought along this time were the Onmitsukidō of the 2nd Division.
Under Shaolin Fon's lead, they quickly discovered the traces left behind by the Intelligence Unit, confirming the location of the Empire of Light's Quincy remnants.
After finding the target, Ailin and Captain Ukitake also ceased conversing as they led the Shinigamis of the 13th Division to follow.
Beyond Ailin's expectations, Captain Ukitake hadn't displayed any doubts towards Yoruichi and Kisuke's departure. Evidently, Captain Ukitake had already known of Yoruichi leaving previously.
"Sigh, I really am still too young..."
Walking behind Shaolin Fon, Ailin shook his head. He had probably been used as a scapegoat by Yoruichi and Captain Ukitake this time.
If nothing went wrong on Yoruichi's side then things would be fine, but if something did happen, Captain Ukitake also had an excuse over here.
Yup, the excuse was that Ailin had pestered him with some unimportant questions occupying his attention. Ailin hoped he wouldn't get set up this time!
Shinigamis possessed extraordinary power, but perhaps to buy time for Yoruichi and Kisuke, Shaolin Fon led the troops of the Onmitsukidō to search for the Intelligence Unit's traces at an efficiency dozens of times slower compared to when Ailin was still part of them.
Yet for a mere twenty kilometers distance, Shaolin Fon actually had the Onmitsukidō circle around for two whole days before reaching their destination.
"Oh? You guys sure took a long time getting here, Captain Ukitake, Captain Ailin."
At the end of the path, Yoruichi and Kisuke Urahara seemed to have already been waiting for some time.
"We've already fully investigated. The 8th Division's intel was correct. There indeed are Quincies existing here."
When Ailin and Captain Ukitake walked over, peering forward from this muddy small road was over thirty tattered thatched huts.
Around the straw huts were farmlands. Most men and young women were laboring in the fields. There were also some frolicking children in the village. Their attire was similar to the wandering souls of Soul Society's Rukongai. Clearly, this era was still considered an "ancient age" to Ailin.
Seeing these people no different from ordinary humans, Ailin's brows slightly creased. "Captain Ukitake, do we have to completely massacre all these people?"
Ailin's senses told him there were over 230 or so people just within this village. Among them were over thirty children under ten years old and over twenty elderly above sixty.
Ever since becoming a Shinigami, Ailin had never once swung his blade at children before. He didn't wish for any exceptions today either.
"No, our goal is to exterminate the Empire of Light's Quincy warriors. Ordinary people are not within our purge range." As if knowing what Ailin wanted to ask, Captain Ukitake directly clarified the objective of this mission.
"Is that so? How do we confirm which of these people are Quincies then?"
Quincies were adepts at spirit particle manipulation. For powerful Quincies, hiding one's Reiatsu was basic ability.
Additionally, Quincies were most proficient in gathering spirit particles to form arrow projectiles for attacking enemies. Even with lower Reiatsu tiers, they could still possess formidable might.
If they didn't voluntarily flare up Reiatsu, it would be impossible for Shinigamis to distinguish Quincies from ordinary people.
"That's simple."
Before Captain Ukitake could reply to Ailin, Kisuke Urahara standing by Yoruichi's side already spoke up, drawing everyone's attention onto him.
They only saw Kisuke Urahara take out a small glass bottle from his clothes. Inside the bottle was half a bottle of liquid that sloshed about as Kisuke swung his wrist.
"This item here is something I coincidentally discovered. It can emit a scent similar to human souls after making contact with air."
After speaking, Kisuke Urahara flicked open the bottle's stopper before tossing the glass bottle down towards the village below.
The glass bottle tumbled through the air, spilling white liquid from its mouth that swiftly volatilized in the air.
"Just this one small bottle of liquid could emit a scent comparable to a thousand human souls after evaporating. I presume the gathering of so many soul scents here will soon attract Hollows over from Hueco Mundo. By then, the people attacking those Hollows will be our extermination targets this time."
Ailin noticed Yoruichi didn't react the slightest when Kisuke said the word "exterminate". Something he didn't know about had probably occurred here causing Yoruichi to gain her own determination.
To avoid rousing the attention of the Quincies in the village, Ailin's group retreated into the woods, only observing the village's circumstances from afar.
They didn't have to wait long at all. Not even ten minutes after Kisuke Urahara's medicine dissipated, roars of Hollows sounded by everyone's ears.
In the village's skies, only those possessing Reiryoku could see pitch black cracks splitting open one by one.