That giant earthworm Hollow had been absolutely massive.
Even though only a small fraction of its lower half remained, Ivan still felt incredibly tiny next to it.
The severed chunk was easily seven or eight times his size.
He greedily devoured every scrap of flesh he could tear off.
If a good portion of its blood hadn’t soaked so deeply into the sand, making it impossible to eat, he would have swallowed the sand, too.
Because of his knowledge of the canon timeline, Ivan knew that everything in Hueco Mundo—even the ground beneath his feet—was composed of high-concentration spirit particles, or Reishi.
Acting on a wild whim, he had actually tried eating the white sand to see if it would boost his Reiatsu.
He gave up after nearly choking himself to death a few times.
It didn’t take long for him to finish off a corpse that vastly exceeded his own body weight.
This time was different.
After downing the earthworm’s half-body, he finally felt a long-forgotten sensation: he was actually full.
Roar!
Wisps of dark gold Reiatsu suddenly swirled around Ivan’s body, and he couldn’t stop himself from throwing his head back and letting out a booming roar.
“Am I…
evolving?” Realizing what was happening, a grin spread across the wide, pale mask covering his face.
An intense feeling of absolute comfort washed over him.
It felt exactly like getting a premium, full-body spa treatment back in his past life.
Boom!
A pillar of dark gold Reiryoku erupted from his body, enveloping him completely.
Within that pillar of light, his physical form underwent a radical evolution.
The phenomenon didn’t last long, dissipating completely after about ten seconds.
As the golden light faded and the swirling dust settled, Ivan’s brand-new form was revealed.
His original four-to-five-meter length had expanded drastically.
Counting his centipede-like tail, he was now roughly seven to eight meters long, nearly double his previous size.
His pale centipede limbs were now etched with streaks of dark gold lightning.
Even the helmet-like mask that completely encased his head sported a matching dark gold thunderbolt pattern.
His humanoid upper torso was now a complex, interwoven tapestry of gold and black markings, making him look far more demonic and eerie than before.
“I’ve evolved into a Strong Hollow!” Ivan said, his voice vibrating with excitement.
Over the past half-month of exploration, combined with his meta-knowledge from the anime, Ivan had pieced together a rough understanding of the Hollow hierarchy.
The original canon only clearly distinguished between ordinary Hollows and Menos Grande.
The Menos were then subdivided into the lower-class Gillians, middle-class Adjuchas, and the highly mysterious, upper-class Vasto Lordes.
But through actual fieldwork and personal experience, he realized that ordinary Hollows had their own distinct evolutionary ladder.
Stage One: Newborn Hollow.
When Ivan first arrived in Hueco Mundo, both he and the lizard Hollow he killed fell into this category.
They had just formed and hadn’t had time to devour enough of their own kind or human souls.
Their power was generally weak, relying entirely on the strength of their human soul before they transformed.
Ivan had easily crushed the lizard simply because his underlying soul was stronger.
Stage Two: Strong Hollow.
After his first evolution, this was where Ivan currently stood.
Stage Three: Giant Hollow.
The massive earthworm Hollow that got one-shot by the mutant Gillian belonged in this tier.
Stage Four: Gillian (Lower-Class Menos).
These towering monsters were the gatekeepers of the Menos class, formed when over a hundred Giant Hollows slaughtered and devoured each other.
Over ninety percent of Gillians looked exactly the same.
The vast majority completely lost their minds, becoming mindless killing machines commanded by the higher-tier Adjuchas.
Only an extremely rare few—like the mutant Gillian Ivan had just seen—retained their intellect, consciously hunting down their own kind to evolve into Adjuchas.
There was also a special subclass within the Gillians: regressed Adjuchas.
If an Adjuchas had a piece of its body eaten by another Hollow during a fight, it would permanently drop a class.
However, these regressed Adjuchas didn’t revert to the standard Gillian appearance.
They kept their Adjuchas form, and their combat power remained vastly superior to a normal Gillian.
Stage Five: Adjuchas (Middle-Class Menos).
Evolved from mutant Gillians through endless slaughter.
They were usually larger than standard Hollows but much smaller than Gillians.
They could command armies of Gillians and use high-level abilities like the Cero, Bala, and Sonído.
But they were cursed to keep eating.
If a Hollow of equal or higher tier took even the tiniest bite out of them, their evolution stopped permanently.
No matter how much they ate after that, the best they could hope for was preventing a regression back into a Gillian.
They would lose their shot at becoming a Vasto Lorde forever.
Stage Six: Vasto Lorde (Upper-Class Menos).
The undisputed apex predators of Hueco Mundo, evolved from Adjuchas with enough potential, or spawned naturally under extremely rare conditions.
They were roughly the size of a human, incredibly scarce, and possessed raw combat power rivaling a Soul Society Captain.
“I still have a long way to go.” Ivan didn’t let the excitement of reaching the Strong Hollow stage get to his head.
He knew that if this was late into the plot, even Vasto Lorde-class Arrancars were essentially cannon fodder.
A Strong Hollow like him was literally just a bug.
Since he still didn’t know the timeline, aggressively grinding for power was his only option.
Otherwise, he might just get vaporized by the collateral damage of two Adjuchas fighting nearby.
That thought brought a fresh sense of urgency.
He quickly focused inward to familiarize himself with his newly evolved body, completely thrilled to discover he had gained two brand-new abilities.
[Ability 1: Reiatsu Concealment] Ivan could suppress his Reiatsu until it was virtually nonexistent.
Only a being with a Reiatsu pool more than a hundred times larger than his own could detect him.
[Ability 2: Lightning Arc] Ivan could channel crackling arcs of electricity across the segmented joints of his centipede lower half.
The downside was that the lightning only coated his body and couldn’t be fired as a ranged attack.
Discovering these two skills filled him with absolute joy.
With these abilities combined with the sandy terrain of Hueco Mundo, Ivan was now the ultimate ambush predator.
He could massively speed up his grinding process.
“And as for a ranged attack…
I think I’ve got one of those, too.” Beneath his mask, a faint, almost imperceptible smirk formed on Ivan’s lips.
The memory of the mutant Gillian firing its Cero kept replaying in his mind like a high-definition recording.
He slowly extended the index finger of his pale right hand.
A speck of black-red Reiatsu began to condense at the tip.
Five seconds later, a beam of black-red light erupted from his finger, blasting toward a distant sand dune.
Boom!
A massive explosion echoed across the wasteland, followed closely by a towering shockwave of sand and dust.