Boom. The Earth Projectiles struck the Hollow's body, only managing to make it pause for a few seconds; their power was extremely weak.
"The power of ninjutsu is drastically reduced." Naruto watched this scene quietly, some preliminary experimental data already forming in his mind.
A jonin who becomes a Hollow experiences a certain degree of power increase but loses all reason, becoming dominated by savage slaughter. Conversely, a jonin successfully transformed into a Shinigami suffers a significant decrease in strength. This is because their internal chakra has just begun to merge with Reiatsu, and the amount of Reiatsu generated is limited, leading to a sharp drop in power.
Shlick. In his line of sight, the Hollow's claw pierced through the Shinigami-jonin's chest. It withdrew the claw, and the Shinigami-jonin collapsed, life status unknown. The Hollow bent down, greedily gulping down the Reiatsu leaking from the Shinigami's body.
Naruto adjusted his glasses, his eyes glinting.
"Hollows possess an innate hostility towards Shinigami. So, after its Hollowfication, it directly attacked that Shinigami without any intention of attacking me. After killing its target, it began to devour the Shinigami to increase its own power."
"This aligns with what Aizen-sensei described about Hollows. They constantly hunt their own kind or Shinigami, growing stronger by devouring them, thereby breaking their limits and evolving to higher levels."
Hollows were divided into two main categories: regular Hollows and Menos Grande.
Regular Hollows were converted from human souls.
Menos Grande typically evolved from regular Hollows that had devoured hundreds of other Hollows.
However, in the ninja world, the chakra within shinobi seemingly met the conditions for regular Hollows to evolve directly, so the Hollows born here were essentially all Menos Grande.
Menos Grande were further divided into three levels.
The first, most basic level was Gillian. They had black outer bodies and white bone masks, were enormous but slow-moving, possessed little intelligence, and merely attacked and devoured their own kind like wild beasts. When they had devoured enough Reishi, they would transform into Adjuchas.
The second level was Adjuchas. Adjuchas would possess beast-form carapaces. They would have high intelligence and immense destructive power, roughly several times stronger than a Gillian. They would also gain the ability to lead vast swarms of Gillians. Even so, they still needed to continuously devour spirits to evolve.
There were two evolutionary paths for an Adjuchas: one, their power would hit a bottleneck, and they would remain Adjuchas forever, unable to increase their strength further; two, they would break through the bottleneck, their power rising to new heights to become the third stage of Hollow, Vasto Lorde.
The third level was Vasto Lorde. Vasto Lorde were the highest level of Hollow. Interestingly, they possessed human-like forms, implying their power was even more concentrated. Aizen-sensei hadn't elaborated on their specific abilities, as no Vasto Lorde had been born in his experiments either. So, this level was still largely theoretical.
However, one conclusion could be drawn from past research: the higher the level of a Menos Grande, the closer it was to human form and intellect. The changes to its original body after Resurrección would also be smaller.
According to Aizen-sensei, Shinigami could undergo Hollowfication, and Hollows could also possess a Shinigami's Zanpakuto. Therefore, the research Naruto and Orochimaru would conduct would target not only Shinigami but also Hollows.
The greatest difference between Shinigami and Hollows was that Shinigami often retained memories of their past lives, while Hollows forgot everything. Due to their evolution through devouring their own kind, Hollows tended to have cruel personalities. It was just unknown if these established principles would apply to these human-derived subjects.
Naruto frowned, murmuring to himself, "This Shinigamified jonin still possesses memories from his life, but his control over Reiatsu is too rudimentary, similar to Haku's situation. The Hollow, on the other hand, has completely lost its reason, possessing only the instinct to devour."
"However, the number of test cases is too small to draw definitive conclusions. I need to increase the sample size." Naruto once again infused Reiatsu into other jonin souls.
"ROAR!" At that moment, the Hollow that had devoured its target turned its bloodthirsty gaze upon Naruto.
"Oh? You want to kill me?" Naruto scoffed disdainfully.
"ROAR!" The Hollow charged towards Naruto, its eyes filled with bloodlust.
"Jonin-level strength is indeed troublesome, but... its intelligence is too low." Naruto flickered, vanishing from the Hollow's sight.
"With Kyoka Suigetsu, I can easily leave the battlefield." Naruto then infused Reiatsu into the souls of other jonin before hiding in the shadows to quietly observe the reactions of his experimental subjects.
Soon, white mist enveloped all five jonin souls. Ultimately, four of them transformed into Hollows, with only one successfully becoming a Shinigami. And that newly minted Shinigami soul was, without a doubt, torn to shreds by the Hollows.
The remaining Hollows then began to slaughter each other, the immense power they unleashed drawing considerable attention.
"It seems the amount of chakra affects the success rate of transformation. The success rate for jonin is significantly higher." Naruto tapped his finger lightly and quickly disappeared. He moved through Konoha, continuously altering souls. However, he held back slightly, spacing out his transformations; otherwise, Konoha might genuinely be destroyed by the Hollows.
Only when about half of his Reiatsu was depleted did Naruto stop, casting a meaningful glance in the direction of Jiraiya and the Konoha jonin.
"That should do it. Today has been quite fulfilling." Naruto strolled leisurely towards the arena, weaving through the ninjas' battleground. Eerily, neither ninja, Hollow, nor Shinigami seemed to notice him at all. Various ninjutsu slid past him, striking their intended targets and causing violent explosions.
The Hollows, not to be outdone, fired Ceros, directly demolishing large swathes of buildings. Black smoke gradually rose from all over Konoha.
Naruto also noticed that the Root shinobi, hidden for so long, had finally shown themselves. Although Danzo craved the Hokage title and had planned for the Third to die, he wouldn't just stand by idly when Konoha faced true calamity.
"At times like this, Konoha is at its most united. How laughable," Naruto chuckled softly. Amidst the flashing lights of jutsu and swirling dust, clad in his white robe, he walked with a calm and composed gait, the sounds of exploding ninjutsu and Ceros echoing behind him, forming a strangely beautiful picture.
Meanwhile, Jiraiya had easily dispatched the two giant snakes with his ninjutsu. His chakra reserves were still plentiful; such a battle hadn't even counted as a warm-up for him. His gaze soon fell upon Shukaku in the distance. He prepared to step in and suppress the Tailed Beast. Konoha was not a place where even a Tailed Beast could rampage freely!
"What is that monster?!"
"Such terrifying creatures!"
"Could it be another Tailed Beast?"
However, before Jiraiya could act, roars and screams from afar caught his attention. He looked over and was stunned to see several monsters with white bone masks slaughtering ninja. Their bodies were resilient, their claws sharp, and they emanated an aura of negative death energy. They could even fire projectile-like attacks from their mouths, powerful enough to instantly pulverize a house.
Under the assault of these Hollows, Konoha was already riddled with gaping wounds. Ruins and severed limbs were everywhere.
"What are these things?" Jiraiya's expression turned exceedingly grim.
"Summoning Jutsu!" He formed hand seals and slammed his palm onto the ground. Instantly, smoke billowed forth.