Boom! Boom! Boom!
Hundreds of blackish-red lightning bolts, like claws reaching from the abyss, descended upon Enkidu, threatening to impale her.
Undeterred, Enkidu faced the Hollowed Ailin's assault. Bound by the Chains of Heaven and its Death Wind Rope, their spiritual pressures were linked. Any injury either of them sustained would be healed by drawing upon their shared reserves. As long as their combined spiritual pressure remained, neither could truly die.
Knowing this, Enkidu fought without reservation. Her attacks wouldn't cause any lasting harm to Ailin.
Clatter!
She raised her right hand, and countless golden chains surged upwards, meeting the falling Zanpakutō in a deafening cacophony of clashing metal. The underground training ground reverberated with the force of their collision.
…
BOOM!
In the blackish-red sky of Ailin's inner world, Hollowed Lin was sent flying by Ailin, crashing into the Sword Hill and carving a deep crater into its side.
Crack… Crack…
Encased in a shell resembling a chrysalis, Hollowed Lin's spiritual pressure increased again. The shell began to shatter, revealing his face beneath.
Ailin's relentless assault had pushed Hollowed Lin to the third stage of his fusion with the Hōgyoku in under half an hour. Like Sōsuke Aizen, Hollowed Lin's evolution prioritized increasing his spiritual pressure.
However, unlike Aizen, whose philosophy had been that "a Shinigami's battle is a battle of spiritual pressure," Ailin and Hollowed Lin sought to transcend the limits of spiritual pressure, pushing it towards higher dimensions.
They were more interested in elevating their existence than in specific Zanpakutō abilities. After all, Ailin, wielding the power of Unlimited Blade Works, could manifest any Zanpakutō ability he desired. He simply needed to collect the "sword element" of that ability and forge it into a blade.
Having discarded other avenues of power, Hollowed Lin's spiritual pressure, at this stage of fusion, far surpassed even Aizen's. Moreover, unlike Aizen, whose form had become increasingly grotesque with each evolution, Hollowed Lin retained his human shape, augmented only by his increasing spiritual pressure, his Hierro, and his high-speed regeneration.
As Hollowed Lin's power grew, the blackish-red in Ailin's inner world deepened, and its edges now ragged as tendrils of dark energy began to seep into Ailin's golden territory.
During the second stage of fusion, Hollowed Lin's spiritual pressure hadn't been able to penetrate Ailin's domain. Now, in the third stage, although the intrusion was slow, like wisps of smoke, it was undeniable.
This marked the completion of Ailin's first objective. For Hollowed Lin to become his "steed," his mount in the pursuit of greater power, their spiritual pressures had to merge completely.
However, Ailin's spiritual pressure was simply too vast. Even with the Hōgyoku's assistance, Hollowed Lin had only reached a level where his spiritual pressure could barely penetrate Ailin's domain after three stages of fusion.
The rate of intrusion was glacial. While Ailin could, theoretically, begin the Hollowfication process now, it would take days, perhaps even weeks, for Hollowed Lin's spiritual pressure to completely permeate his own.
He'd have to suppress his Shinigami powers for that entire duration, leaving him vulnerable. Ideally, the process should be instantaneous.
Moreover, the duration of his Hollowfication would depend on Hollowed Lin's spiritual pressure reserves.
Such a process, with so many drawbacks, was unacceptable to Ailin. He didn't want a Hollowfication that required days of preparation. He envisioned something like Ichigo's or the Visored's, an instantaneous transformation where his Shinigami powers were suppressed, and his Hollow powers would manifest as a mask.
To achieve this, the gap between his and Hollowed Lin's spiritual pressures couldn't be so significant. If their powers were too disparate, the time required for Hollowed Lin to permeate his spiritual pressure would become his greatest weakness. The longer the process, the greater his vulnerability.
Only when Hollowed Lin's Hollow reiatsu could instantly infiltrate his own would his training be considered complete.
"So strong. Is this his true power?"
As the Hōgyoku enhanced his strength, Hollowed Lin became more aware of the vast gulf between them.
BOOM!
The chrysalis shattered completely. Hollowed Lin had fully integrated the third stage of the Hōgyoku's power, and with this increase in power, the boundary between gold and blackish-red in Ailin's inner world shifted. The tendrils of Hollow energy thickened and its intrusion accelerated.
At this rate, it would take only half a day for Hollowed Lin to completely permeate Ailin's spiritual pressure. From three days to half a day. The fusion with the Hōgyoku was progressing exponentially faster.
However, as Ailin had pointed out, even the most powerful ability was useless if it couldn't be instantly deployed. Half a day was far too long. Anything more than three seconds was unacceptable.
Three seconds was his absolute limit. If Hollowed Lin, even after fully merging with the Hōgyoku, couldn't infiltrate his spiritual pressure within three seconds, his usefulness would be significantly diminished.
Both Ailin and Hollowed Lin, sharing the same memories, understood this. Neither knew what lay beyond the Soul Society. If the world outside was as hostile as Ailin suspected, only those with the power to create worlds could survive. Ailin, upon leaving, might be instantly annihilated.
Regardless of the dangers, once the Thousand-Year Blood War ended, Ailin would leave the Soul Society to explore the unknown. By then, his power would have reached the limits of the Soul Society, with no further room for growth within its confines. He would be like Ichibei Hyōsube, leader of the Zero Division, immortal as long as the concept of "sword" existed within the Soul Society. Even if he died, he could be reborn from any blade.
For Ailin, the Soul Society had become a gilded cage. Were he a native of this world, he might have accepted his fate, perhaps even becoming a protector of the Soul King, like Ichibei, safeguarding the world's balance.
But Ailin carried the memories of another life, another world. If the Soul Society existed, then perhaps other worlds did as well: the Fate world, the Shakugan no Shana world, the Inuyasha world, Sword Art Online, Naruto, One Piece, Demon Slayer… Were these worlds part of the same universe, or scattered across a dimensional sea? Could he find them after leaving the Soul Society?
Moreover, the Soul Society was simply a fictional world from a manga he'd read in his past life. He didn't know its connection to his previous world. Perhaps, if he could find that link, he could return home.
Regardless of his ultimate goal, Hollowed Lin was an essential part of his plan. The stronger Hollowed Lin became, the greater Ailin's power would be. While he might not achieve the Soul King's "Almighty" power with just Shinigami and Hollow abilities, in terms of raw strength, he didn't believe he would be inferior.
After all, within Unlimited Blade Works, countless powerful Zanpakutō awaited his call, each one was a potential source of immense power. If he were to draw Ichibei Hyōsube's Ichimonji, gaining the ability to rename anything, granting it power equal to its new name, he could simply name himself "Soul King" and claim that power for himself.
"Two stages remaining…"
Ailin looked down at Hollowed Lin, wreathed in blackish-red spiritual pressure. "Ichigo Kurosaki's Hollow power, before its true nature was revealed, was called 'White.' I, too, will follow their lead and call you 'Hollowed Lin.'"
"Aizen, during his fusion with the Hōgyoku, couldn't accept being surpassed by a human. His fourth and fifth fusions were… misguided. In the fourth stage, he merged with his Zanpakutō, reclaiming its power. And in his final fusion, he transformed into a grotesque, six-winged creature with a black mask."
"Hollowed Lin, learn from Aizen's mistakes. I need your spiritual pressure, not your abilities."
Ailin's tone turned serious. He acknowledged that Aizen's power had increased after choosing to prioritize combat abilities. But that path had deviated from his initial goal of maximizing spiritual pressure.
Merging with his Zanpakutō, reclaiming its power, wasn't a complete deviation. A Zanpakutō was, after all, a part of its wielder. This fusion was similar to Kirio Hikifune's research into integrating Temporary Souls to enhance spiritual pressure. Thus, when Aizen's fusion regressed, he reverted to this fourth stage. With Kyōka Suigetsu's abilities, it was still a viable path.
However, this path wasn't an option for Hollowed Lin. Ailin's essence was "sword," his ability "sword creation." He possessed countless Zanpakutō within Unlimited Blade Works. To quote Gilgamesh, the King of Heroes from the Fate world: "I know not what treasures lie within my vault. But if it is a treasure, it will undoubtedly be found within my Gate of Babylon."
The same applied to Ailin. Any "sword" within the Soul Society would appear in Unlimited Blade Works. They awaited his call, his recognition, to become a part of his power.
Merging with so many Zanpakutō, reclaiming all their abilities, was beyond the capacity of even the replica Hōgyoku. Even the Left Hand of the Soul King, which governed evolution, couldn't grant such power.
Thus, this path was closed to Hollowed Lin.
"Tch. I don't need you to tell me that!" Hollowed Lin scowled.
Having become a Hollow, he was now truly Ailin's other half. The first three stages of fusion, following Aizen's example, had been easy. But from the fourth stage onward, their paths diverged. He didn't know how to proceed.
The Hōgyoku manifested its wielder's desires. But Hollowed Lin didn't have a plan, a specific desire for his next evolution. How could the Hōgyoku grant a wish that hadn't been made?
He felt his fusion with the Hōgyoku stalling. He couldn't progress without a clear vision for his fourth stage.