Judging by Captain Ailin's past actions, he still possessed certain attachments to this world. Leaving aside others, Haruko Kuchiki was undoubtedly his strongest link.
Kisuke Urahara reasoned that, if only to prevent significant upheaval in Haruko's life, Ailin wouldn't turn against the Soul Society. To a certain extent, Ailin stood on the same side as the Gotei 13.
"Rest assured, Captain Ailin. From now on, I will cease any actions directed against you."
Kisuke assured him.
Although Ailin didn't know the conclusions Kisuke had drawn, he found this agreeable. If Kisuke refrained from provoking him, it would save him considerable trouble.
"It doesn't matter to me. I only offer such chances once. The next time you act against me, I will kill you instantly."
Ailin snapped his fingers, and the spatial ripples in the sky vanished. Urahara and the others, despite Ailin's casual tone, felt a chill. They knew he meant it. Any further aggression towards him would result in their immediate deaths.
Suddenly, Ailin's gaze sharpened on the aerial battle between Gin Ichimaru and Shinji Hirako.
…
"Damn, this guy adapts quickly!"
Shinji wiped the blood from his face as he watched Gin seriously. He had released his Zanpakutō, Sakanade, but found himself on the defensive.
Aside from a lucky strike at the beginning, capitalizing on Gin's unfamiliarity with Sakanade's ability, he hadn't landed another blow. Gin, having adapted to its effects, seemed completely unaffected. This level of mental control was beyond Shinji's comprehension.
"You're too weak, Captain Hirako."
Gin spread his hands with a faint smile. "I suppose you haven't experienced Captain Aizen's Kyōka Suigetsu. Sight, touch, smell, hearing, spiritual awareness… When every sense could be deceiving you, you understand the constant fear of being near Captain Aizen. One must always be vigilant, always questioning: Has Captain Aizen already controlled my senses? Is what I see, hear, and touch… real?"
"I developed a little trick, a way to distinguish between reality and illusion, known only to me. I was rather hoping to test its effectiveness against your ability, Captain Hirako. But alas, your Zanpakutō requires no such trickery. One simply has to do the opposite of what one intends."
"For example, if I want to release my Zanpakutō backwards…" Despite his words, Gin pointed his Zanpakutō directly at his own chest. "Shoot to kill, Shinsō!"
He whispered, and his Zanpakutō extended rapidly towards Shinji.
Swoosh! Swoosh!
Shinji dodged frantically while parrying Gin's relentless assault. He was outmatched in raw power, and Sakanade's ability was useless against Gin's adaptability. Gin's words hinted at an almost inhuman mental fortitude. What kind of conviction could grant such resilience?
Still, Shinji couldn't accept Gin's dismissive comparison of Sakanade to Kyōka Suigetsu. If Love Aikawa and the others hadn't been nearby during that battle over a century ago, he wouldn't have lost.
Splat! Splat!
Cuts appeared across Shinji's body, but a smile touched his lips. "So, you think my ability is inferior to Aizen's? Not even worth testing your little trick?"
"Then allow me to show you… true illusionary power…"
"Bankai – Sakasama Yokoshima Happō Fusagari!"
As Shinji chanted, his spiritual pressure transformed into a golden flower bud that enveloped him.
True illusionary power. While Aizen's Kyōka Suigetsu was formidable, Shinji believed his Bankai was superior.
Kyōka Suigetsu created illusions. Sakasama Yokoshima Happō Fusagari, however, distorted perception itself, turning enemies into allies, allies into friends. Its only drawback was its indiscriminate nature, affecting friend and foe alike. Thus, Shinji had to be careful not to ensnare his own comrades. It was also useless against a single opponent.
Distorted perception wouldn't cause someone to mistake themselves for their enemy, to commit suicide. This ability was the source of Shinji's reputation for invincibility in group battles. He could face hundreds, even thousands, of enemies, release his Bankai in their midst, and watch them destroy each other. Once only one remained, he would deactivate his Bankai and finish the survivor.
Now, with only Gin as his opponent, his Bankai's power was theoretically useless. However, as Gin attacked, Shinji's form shifted to another battlefield, the clash between Barragan Louisenbairn and Soi Fon.
Both Gin and Barragan were caught within the range of Shinji's Bankai and shifted their attention.
"Shinigami! All Shinigami must die! Rot – Arrogante!"
With a thunderous cry, Barragan transformed from a decrepit old man into a skeletal king wreathed in black miasma. He gestured towards Gin, and the miasma surged forward. This Respira, Barragan's signature ability, could rot anything it touched.
Barragan's power was formidable, worthy of a former king of Hueco Mundo. However, its speed was glacial to Gin. Still, he found himself at a disadvantage. He could release his Bankai, kill Barragan before his Zanpakutō was completely corroded, but that would damage his blade. He wouldn't risk that before killing Aizen, before reclaiming what Rangiku had lost.
He gathered lightning in his palm. "Hadō #88. Hiryū Gekizoku Shinten Raihō!"
A powerful bolt of lightning erupted towards Barragan. Several captains watching the scene were surprised. Gin was known for his speed, his cunning, his deadly blade work. No one had suspected his Kidō prowess. A silent incantation of Hadō #88…
Well, several captains present could achieve that. Captain-Commander Yamamoto could silently unleash Hadō #96. Shunsui Kyōraku and Jūshirō Ukitake undoubtedly possessed similar capabilities. Toshiro Hitsugaya, though not a Kidō specialist, could at least silently cast Bakudō #81. And Kisuke Urahara, a Kidō master, surpassed them all, perhaps second only to Ailin. His Kidō seals within the Hōgyoku could even restrain Aizen after he had merged with it.
Yoruichi Shihōin and Soi Fon, though less skilled in Kidō, possessed exceptional control over their spiritual pressure. Shunko, Mukyū Shunko, and Raishin Senkei granted them immense destructive power without relying on Kidō.
Isshin Shiba, capable of sealing the Dangai for three months to allow Ichigo to master the Final Getsuga Tenshō, clearly possessed some Shiba Clan techniques.
Among the captain-class fighters, only Shinji, Love, Rōjūrō, and Kensei Muguruma of the Visored seemed to lack significant Kidō abilities.
Barragan raised his hands, and a dense black fog of Respira formed before him. The Hiryū Gekizoku Shinten Raihō struck the fog, causing muffled explosions within its depths. Barragan's Respira, however, managed to rot the lightning before it reached him.
Gin narrowed his eyes. Barragan's ability was indeed formidable, but its speed seemed linked to his spiritual pressure. While buildings crumbled instantly upon contact, Kidō, condensed from spiritual energy, took longer to corrode.
"Bakudō #81. Dankū!"
As Barragan's Respira surged forward again, Gin didn't retreat. He cast Dankū, the defensive Kidō said to be impervious to any Hadō below #90.
Bang!
The black miasma struck the pale yellow barrier. Seconds later, cracks appeared on its surface, spreading rapidly as the Respira corroded it.
Gin now understood the nature of Barragan's power. Dankū could block it, indicating it was a Kidō-type ability. The fact that it could corrode Dankū, however, placed its power above Hadō #90.
Defeating Barragan was both simple and complex. One could either overwhelm him with speed, landing a fatal blow before one's Zanpakutō was completely rotted, or unleash a Kidō powerful enough to pierce his Respira.
He glanced at Aizen, still trapped within Yamamoto's flames, and decided against prolonging the fight. "Hadō #91. Senjū Kōten Taihō!"
He gestured with his left hand, and a cascade of ice erupted towards Barragan, solidifying into a massive iceberg. While this wouldn't injure Barragan, it would buy Gin some time.
He turned his attention to the golden flower bud in the sky.
"Oh dear, I didn't expect to be stopped by you…" Shinji deactivated his Bankai and emerged from the golden bud. Even his pride couldn't deny Gin's superior strength. "But defeating me… won't be so easy!"
He placed his left hand on his face, and black spiritual pressure gathered at his fingertips. He ripped his hand downwards.
Boom!
A white, bone-like mask appeared on his face. His spiritual pressure increased, becoming less Shinigami-like, more Hollow. Hollowfication.
"Come!"
Whoosh!
He dashed towards Gin. Since his Zanpakutō's power was useless, he decided to relying on his swordsmanship. However, Gin's swordsmanship, honed under Ailin's tutelage, was superior. Even without releasing his Zanpakutō, he effortlessly suppressed Shinji.
Slash! Slash! Slash!