"Engraved Ninja Tools?"
The moment he heard Kagetsu's words, Rasa's mind immediately thought of that name.
As the Hidden Sand Village (Sunagakure) had the closest ties with the Hidden Leaf (Konohagakure)—so close that they were practically a solid alliance built on mutual benefit—they naturally paid close attention to Konoha's intelligence, especially when it concerned technological developments.
Of particular importance was Konoha's Department of Scientific Ninja Tools, which had the greatest impact on Sunagakure's own interests.
Many of the department's research projects, unless they were classified at the highest level, were more or less known to the Sand.
And once something entered wider circulation, the information they could gather increased significantly.
The "Engraved Series" of ninja tools was one such example.
In fact, part of that very technology had already been shared with joint Konoha-Suna commercial ventures, and had been implemented in certain puppet designs.
But that was still just ninjutsu.
Rasa and his most trusted jōnin subordinates each owned a personalized piece of ninja equipment from the Engraved Series, tailored to their individual needs.
Take Baki, for example. His gloves had a special property that slightly amplified his wind-nature chakra.
In addition to the ninjutsu that could be inscribed onto the tools themselves, this allowed him to unleash Wind Release techniques with greater power and speed—without increasing his chakra output.
"You could think of it that way," Kagetsu replied. He seemed slightly surprised that Rasa had connected it to the Engraved Ninja Tools, but still nodded in acknowledgment.
"You can consider it a ninja tool that allows chakra to be converted into Hollow spiritual energy."
"Ever since the incident in Rōran," he continued, "my sensei and I have dedicated immense time and effort to researching the power of Hollowfication."
"Because if Mukade from the future underwent a Hollow transformation in the final moments, then the possibility of Hollows existing in the future is no longer theoretical—it's a certainty."
"It was both a warning… and a message."
"So that's how it is!" Rasa was momentarily stunned after hearing everything.
Yes… If even the future version of Mukade was infected with Hollow powers, then doesn't that mean Sunagakure in the future must have fought against Hollows—and possibly even harnessed their power?
Is this one of the changes in the future? Or… is the Hollow Catastrophe destined to happen no matter what?
The idea that the future was bound to unfold this way was so convincing, Rasa couldn't help but believe it—if only just a little.
Then, in that future, wouldn't he—his future self—have accepted this change and made reforms accordingly?
The more Rasa thought about it, the more he felt that his future self must not have decided to seal off the Ryūmyaku.
"Want to test these ninja tools?" Kagetsu pointed to the set of tools placed in front of him and asked Rasa.
Rasa silently nodded and waved his hand, signaling the Suna-nin behind him to step forward and select their equipment.
And as for test subjects?
There were plenty sealed just outside the oasis.
Releasing just one of them would be enough to test the tools' effectiveness.
Of course, the large Hollow he had personally sealed away wouldn't be among them—it was too dangerous.
That one had enough destructive power to genuinely threaten a kage's life.
Naturally, to get the best results out of the tools Kagetsu had provided, only elite jōnin from Sunagakure would participate in the test.
Outside the oasis—
As a seal engraved on a small hill was lifted, a Hollow shaped like a scorpion darted out from the sand dunes in a flash.
"Trying to escape? Not completely brainless, are you?"
Watching the scorpion Hollow disappear into the swirling sands, Rasa narrowed his eyes slightly. His understanding—and caution—toward Hollows grew even deeper.
But since this was a test, there was no way he'd let the Hollow escape so easily.
His hands formed seals rapidly. Then, crouching down, he pressed both palms onto the surface of the sand beneath him.
A series of powerful tremors erupted from Rasa's palm, spreading outward in a fan-shaped wave.
Each pulse stirred up waves of sand, rolling violently across the desert like a storm in the sea of sand.
Soon, under the force of the expanding shockwaves, the escaping Scorpion Hollow was blasted out of the dunes.
It was flung high into the air, twisting and flailing as it dropped back toward the ground.
A Jonin Sand shinobi, equipped with a compact bow, gripped the weapon tightly. His hand poured chakra into the bow with intense focus.
As the chakra surged through the small bow, it began to shift before everyone's eyes—changing from its tiny form into a massive energy construct resembling a chakra-infused longbow.
With a fluid motion, the shinobi pulled back the shimmering string. From nothing, a dark blue arrow began to form, solidifying from pure chakra.
Whoosh!
The arrow vanished the moment the string was released. In a flash, it struck the Scorpion Hollow, which was still suspended in midair and hadn't yet fallen to the ground.
The arrow pierced clean through, embedding deep into the creature's body. Its steel-like hide—known for resisting countless ninjutsu and taijutsu attacks—offered no defense at all.
The chakra arrow shattered its defenses like they were paper.
From afar, an invisible wave of sound washed over the group.
It wasn't noise—it was a spiritual shock, something akin to a genjutsu, striking directly at their minds.
Rasa and the others felt it clearly: pain, and an overwhelming surge of rage.
The Scorpion Hollow finally hit the ground, but before it could make a move, a sharp blade of light came crashing down from above.
Its scorpion tail whipped through the air in response, striking at the approaching Sand shinobi.
But this elite was clearly a taijutsu specialist—he twisted his wrist midair with lightning-fast reflexes.
The descending blade curved and met the incoming tail in one clean, decisive strike.
A segment of the scorpion tail was sliced clean off.
A sand clone crumbled under the strike of the scorpion tail.
Right after that came a flurry of arrows.
The scorpion Hollow had no time to defend itself.
It was completely torn apart under the relentless barrage, leaving behind only a broken mask that continued to erode in the desert wind.
"Did we… kill it?"
Rasa was a little surprised as he looked at the vanishing figure of the Hollow.
To actually kill one of them—it usually meant pouring an overwhelming amount of damage into it.
If the damage wasn't enough, the Hollow's hierro (steel skin) would only weaken slightly, and then its high-speed regeneration would undo even that.
In general, the cost of killing a Hollow was far higher than simply sealing one.
And that only applied to regular Hollows.
As for a Menos Grande?
Even if Rasa gave it everything he had, he could at best break through its defenses and restrain it to some degree.
To actually kill it with sheer damage—Rasa knew very well that was beyond his current power.
However, if he had a specially crafted sealing gear made specifically to counter Hollows, then maybe—with his own strength—he might have a chance to bring down a Menos for good.
As for chakra?
Rasa, who had sealed the One-Tail into himself using a forbidden sealing technique, didn't worry about that at all.
Though he wasn't a perfect Jinchūriki, Konoha had resolved the sealing technique's instability.
In critical moments, Rasa could still forcibly draw on the power of Shukaku.