There was a lot of work Silas had managed to pull off in one night.
First, after defeating two squads, he had to restore their vitality, healing them of any injuries. This was done with a spell he had learned from Hachigen.
After healing them, he had to use Enrakyōten's ability as Kyōka Suigetsu. To his assumption, although it wouldn't be years until the Tōshirō and Retsu would see the release of his Kyōka Suigetsu, the Zanpakutō's ability still worked.
This was due to their familiar spiritual pressures. Meaning, it didn't matter what time period Silas was in. So long as the Zanpakutō recognized its targets' spiritual pressures, its hypnotic abilities could still be used.
Those who had never seen it before were not his priority. Leaving them unconscious, he woke up the captains. Immediately, they saw their squad members collapse, following a noxious gas in the area.
The two searched hard for sources, with Tōshirō taking the lead. Retsu tried her best to heal her members, and Silas did a perfect job making her believe she was expelling the fake poison in the air.
After Tōshirō destroyed what he thought was the source of the gas, a plan laced with venomous spirit particles, he destroyed it. Silas caused the illusion to cease before departing the area. Doing so allowed the other squad members to awaken.
As for the captains' memories? Silas erased them.
This was only possible because of three things: Soul manipulation and the Hōgyoku.
It was a highly dangerous and unpredictable procedure, as it could have damaged their Souls. But Silas was willing to take such a risk.
Things proved to be successful when not a sliver of doubt was expressed by Retsu. She, being a cautious Soul Reaper whose sense had been refined over the centuries, had truly forgotten and believed the entire act.
So he named it "Shinen no Jyouchaku", meaning "Annihilation of Memories".
The only two flaws in his plan were that Retsu had also forgotten his desire for her to meet his other self in the laboratory when the time came, and her Bankai was broken.
Erasing memories from spirits and Souls was a simple feat, but restoring them after they'd already been lost wasn't easy. Something like that was nearly impossible. For now, Silas had to leave Retsu and consider another method.
She wouldn't attempt to use her Shikai or Bankai for some time. And as far as he was concerned, she—like most Soul Reapers—didn't communicate with their Zanpakutō regularly.
Perhaps he could develop a new spell with the Hōgyoku, but there was no need to rush. He had a lot of time to spare.
And the real reason he went to such lengths in the first place was not only to test his might but also to ensure the story flowed in his direction.
• • •
Silas stood in the center of the laboratory. The dimly lit area was never a bother.
He tilted his head back, considering the path he was going to tread. After having perfected the teleportation spell, it was time to step foot in Hueco Mundo for the first time.
His fingers traced the air. Power thrummed beneath his skin as he flicked his wrist. A quick surge of spirit particles flowed outward. Before him, space warped and buckled, the fabric of it tearing open like a rotten curtain.
The Garganta.
A raw, gaping wound in the world. Its edges shimmered with a sickly darkness. Silas knew what awaited—the relentless spiritual pressure of the void, the crushing density that could suffocate and reshape a weaker Soul. But for him, this was merely an antechamber.
The moment had come. He stepped forward and crossed the threshold.
The Garganta closed behind him with a sickening snap, plunging him into darkness. Yet he felt no disorientation, no crushing weight. The vast, pulsating energies of the Garganta washed over him like a warm breeze. His own power buoyed him effortlessly.
From what he understood, those who entered the Garganta needed to form a platform from their own spiritual pressure to cross. But Silas hadn't done that.
The secret? There were none. His power mixed with the Hōgyoku had amplified his spiritual pressure to levels that dwarfed the mightiest captain, making him all but immune to the Garganta's crushing force. Unlike those before him, he needed no careful constructions and no platforms to tread this alien territory.
He was flying.
Or rather, his body was propelling through the dense spiritual pressure around him. The energy swirled around him, allowing him to soar through it as if swimming in the ocean. Tendrils of the void reached out, probing but finding no weakness to exploit.
Where a lesser being would buckle, Silas thrived.
The Garganta stretched endlessly before him, a winding black tunnel woven of the spiritual detritus of worlds. Like a moth guided by some unseen flame, Silas let the pull guide him.
Flickers of light pierced the darkness, first faint, then growing brighter. He hurtled on.
Then, without warning, the light exploded into a blinding burst. Silas remained calm. He emerged from the vortex of light and came to a complete halt on solid ground.
His senses, honed over centuries of battle and pursuit, were recalibrated in an instant. A new light covered his face—not the harsh glare of the sun, but an eerie, perpetual twilight.
He stood on the crest of a vast, bone-white dune. Sand, fine and almost powdery, stretched away in undulating waves, broken only by the jagged spires of what looked like petrified trees. The sky was a shroud of unbroken black, the inverse of the desert floor below.
An immense, misshapen moon hung low on the horizon, giving off the same pallid light that suffused the landscape. There was no doubt about it.
He had done it.
From all the times he's watched and read contents from Bleach, he was experiencing what no man could ever imagine.
He defied the confines of the Soul Society, tore open the boundary between worlds, and emerged into the other world: Hueco Mundo!