Inside a unit within the Hidden Cloud Village of the Land of Lightning, Tanaka Haruki remained undeterred as he began explaining the contents of the second sealed scroll.
"This contains special ninja tools I personally developed," he said calmly. "They're powerful enough to kill a jonin."
"You developed a weapon that can kill a jonin?" Yeyue couldn't help but speak up, her voice filled with skepticism.
She had only recently attained the rank of jonin herself. The idea that a ten-year-old child had engineered a weapon capable of taking out a jonin was beyond belief.
The Third Raikage and Dodai exchanged looks—confused, yes, but increasingly intrigued. The presence of 1 billion ryo had already elevated their opinion of this boy. Clearly, he wasn't some ordinary student talking nonsense.
"I'll need a secluded and open area to demonstrate," Tanaka Haruki added, offering no further explanation.
There was no point in elaborating further. At this point, only a live demonstration would prove the weapon's effectiveness—and Haruki was confident.
Though the weapon's accuracy might be limited due to the primitive conditions under which it was crafted, its destructive power was undeniable.
"We'll use my training hall," the Third Raikage said after a glance at the boxed wealth beside him. He stood up decisively and exited the office, gesturing for Haruki to follow.
Haruki moved quickly behind him. Dodai sealed the 1 billion ryo and followed with the two scrolls, with Yeyue close behind.
They soon reached a spacious underground training chamber built into the mountain beneath the Raikage's tower. This was the Third Raikage's personal training hall, equipped with weights and training tools—exactly what one would expect from a village like Hidden Cloud, which prized raw physical strength.
Despite being called a training hall, the room was massive—100 meters long, 100 meters wide, and 50 meters tall, supported entirely by reinforced steel walls. It was incredibly durable.
The three senior ninja stood in silence, watching expectantly.
Without wasting time, Tanaka Haruki took the second sealed scroll from Dodai's hands and unsealed it, revealing three massive contraptions inside.
"These three weapons were inspired by childhood toys—blow darts and fireworks," he explained. "They use detonating tags as a propellant to fire metal projectiles through steel tubes. The power depends on the quality of the tags and the strength of the projectile's material."
He picked up the smallest of the weapons—a long rifle—and continued his explanation.
"I couldn't purchase high-grade detonating tags with my current status, so I used the lowest grade available. I've bundled ten tags per bullet."
He raised the weapon. "I call this the Vulcan Gun. It's designed for long-range precision strikes."
He demonstrated by inserting a bullet—thick as a grown man's thumb—into the rifle's magazine and chambering it with a rotating bolt. The rifle itself was nearly two meters long, resembling the anti-tank rifles he remembered from a World War II film in his previous life. It was little more than a steel tube, but the raw kinetic force behind it could pierce tank armor—an idea that said a lot about the potential recoil.
Even now, Haruki hesitated slightly. This was untested. The bullet packed ten exploding tags. If the gun held together, the recoil might still seriously injure him. There was even a risk of the weapon backfiring.
"This thing needs serious physical strength to operate," Haruki admitted. "I'm afraid I don't have the endurance to use it safely."
He turned toward the group, eyes settling on the muscular Yeyue.
"Would you be willing to test it?"
Yeyue didn't hesitate. "How does it work?"
She stepped forward and took the weapon eagerly.
Despite her impulsive nature, she wasn't foolish. From Haruki's earlier explanation, she had deduced the concept: use explosive chakra tags to propel a metal bullet—simple, but effective.
"Chakra goes in here," Haruki instructed, pointing. "That triggers the detonation inside the bullet. But be careful—it's never been tested. The weapon's material isn't great, and it could explode."
After giving his warning, Haruki wisely retreated—far. He even ducked behind the platform for cover.
Dodai glanced at Haruki hiding behind him, silently noting that the kid had just used him as a human shield. Still, he said nothing and turned his attention to Yeyue.
The Third Raikage also watched with growing interest. The principle was sound—but how powerful would it actually be?
Yeyue took aim at a thick pillar on the opposite wall.
"Boom!"
A thunderous explosion echoed through the chamber. Fire flared from the muzzle, and a walnut-sized dent appeared in the steel wall.
The three adults immediately rushed forward to inspect the damage—and their expressions turned serious.
The dent might seem small, but it was carved into solid steel—ten centimeters thick. The sheer force required to deform that kind of material was immense.
If a human body had been hit, even the torso wouldn't have survived. Defense would require chakra-infused armor or advanced defensive jutsu with elemental properties.
Dodai retrieved the warped, embedded bullet with a kunai and examined it.
"The bullet's material is too soft. If we swap it for a harder alloy, penetration would improve dramatically," he assessed.
Compared to a standard kunai or shuriken, which might pierce skin but rarely passed through a body, this weapon was a game-changer. Limbs would be blown off; direct hits to the chest would be fatal.
"But the accuracy needs serious work," Yeyue noted critically.
She stared at the pillar. The Vulcan Gun had missed her intended target zone by several centimeters. On top of that, the barrel was already warped from the recoil, and the shell had jammed inside.
Still, those were solvable problems.
Haruki took the feedback in stride. He was prepared.
"I've considered this. If we add spiral grooves to the barrel to induce bullet spin, the trajectory will stabilize and accuracy will improve—but it's hard to manufacture right now.
"We could also enhance the weapon with elemental chakra. Earth release could reinforce the barrel and bullet for better durability. Lightning and wind release could enhance penetration and precision. Wind release, especially, could reduce drag and improve velocity.
"Water release could cool the barrel for rapid firing, while fire release could mimic detonating tags—sealing a fire-based explosion within the bullet itself for a delayed detonation, almost like fireworks…"
As Haruki shared his thoughts, Dodai's eyes lit up. The possibilities were endless.
If realized, this weapon could be a battlefield revolution. The range alone—likely over a thousand meters—far surpassed most ninjutsu.
No jutsu in the current era had that kind of reach.
Yeyue gently ran her hand across the Vulcan Gun, still warm from the blast. Her eyes glimmered with obsession. She looked as though she were about to kiss the thing. She had fallen in love with it—clearly wanting to own the ultimate version once it was complete.
The Third Raikage, meanwhile, turned his eyes to the other two large weapons that had come out of the scroll. Judging from their size and design, they promised even greater destructive power.
Dodai and Yeyue also glanced toward the remaining two prototypes, visibly excited.