The Shinobi Prosthetic was a crucial component of Naruto's combat system in his previous life.
Some of its functions were admittedly unnecessary for him now.
After all, the ninja arts unique to this world could already accomplish—and even surpass—many of the things the prosthetic arm was designed to do.
However, the grappling hook at the core of the Shinobi Prosthetic was still something that could significantly enhance his overall strength.
The prosthetic arm had been his livelihood in his previous life.
Although he hadn't personally built it from scratch back then, he had modified and upgraded it countless times—if not a thousand, then at least several hundred.
He was thoroughly familiar with its structure.
What he needed to do now was simply recreate it, piece by piece.
The only real problem was—
He still had both arms.
So he needed to find a new approach:
how to install the Shinobi Prosthetic while keeping its core functions intact—
without chopping off his own arm.
As for whether he'd ever considered amputation?
His hands were perfectly fine.
Especially factory-original hands—they were comfortable to use.
---
Their current D-rank mission was fairly simple—just a lot of work.
Weeding farmland.
Still, the three of them were already experienced at this sort of thing. Unlike the first time, it didn't take two full days.
This time, they managed to finish before sunset.
"My back's broken! Carry me home!"
Izuno staggered onto a patch of flat ground and collapsed with a thud.
"You can just die out here," Naruto rolled his eyes. Compared to the two half-dead teammates, he still looked energetic—thanks to the Nine-Tails' chakra.
"Lei-boy, go slap him twice! He's way too arrogant!" Izuno groaned.
"I'm dead," Raemon muttered.
"Let's go. I'll treat you to the hot springs," Naruto said, glancing at the sky.
"Say that earlier!"
"Coming right up!"
"Didn't you say you couldn't walk anymore?"
"I'm not dead yet!"
"Weren't you dead, Raemon?"
"Revived."
"..."
---
Hot Spring District
"Wooooh—!!"
Raemon Koshiki's expression was outrageously exaggerated.
"People who know would understand you're soaking in a hot spring," Naruto muttered, placing a hot towel over his forehead. "People who don't might think you're being tortured."
"You don't get it," Raemon chuckled. "After extreme exhaustion, hot springs fix everything."
"Whose life experience is that?"
Naruto, speaking as someone who'd lived before, was fairly certain this wasn't something a thirteen-year-old should be saying.
"My uncle's."
"Got it."
Hot springs had countless benefits.
The only thing Naruto found lacking was the absence of a pair of gentle hands to help loosen his tense muscles.
"...Naruto."
"Yeah?"
"Say—if some kind of transportation existed in this world… fast enough that you could leave Konoha in the morning and reach the Fire Capital by noon, and capable of transporting huge amounts of supplies—what do you think the world would become?"
"I'd still eat three bowls of rice per meal."
"...I'm being serious."
Raemon pinched the bridge of his nose, trying to calm his overworked brain.
"Not realistic," Naruto replied.
"Huh?"
Naruto removed the towel from his forehead.
"If something like that really existed, then communication between people and regions would grow tighter. The economy would boom. Maybe everyone would become more prosperous…"
…and the territory a nation could effectively control would expand as well, he added silently.
"Isn't that a good thing? Then why is it unrealistic?" Raemon asked, puzzled.
"Mm." Naruto struggled to turn over in the water.
"Even if such a thing existed—who builds it? Who maintains it?"
"And who can guarantee that enemy ninja wouldn't sabotage it?"
Compared to the immense difficulty of construction, destruction would be absurdly easy.
A few explosive tags would be more than enough.
"So… does that mean it really has no chance of existing?" Raemon muttered dejectedly.
"It could," Naruto said. "When the ninja world enters a period of relative peace."
What Raemon wanted to build was, in Naruto's eyes, essentially an alternate-world high-speed rail.
It wasn't a bad idea.
On the contrary—it was excellent.
So excellent that "enriching the nation and strengthening the people" wouldn't be an exaggeration.
If Raemon ever completed the design, and if it reached the hands of far-sighted leaders, it would absolutely be promoted on a massive scale.
But the real problem was—
What was the defining nature of the ninja profession?
Infiltration. Assassination. Sabotage.
You might want to enrich the nation and strengthen the military—but sometimes what blocks such policies isn't internal resistance, but external threats.
You pour massive funds and manpower into construction, and enemy ninja blow it all up with a single explosive tag.
Cry all you want—there'd be nowhere to cry to.
Could Konoha defend such infrastructure?
Maybe in the past.
But after the Third Great Ninja War, top-tier fighters were dead or gone.
It was… uncertain.
What Raemon envisioned simply couldn't be implemented steadily unless the world entered a relatively peaceful era.
In Naruto's view, the current tension in the ninja world was so high that even a minor spark might ignite a Fourth Great Ninja War.
The very nature of the ninja profession dictated that, from time to time,
there would be a "population purge" and a redistribution of resources.
After all, the number of missions was limited—and every village was engaged in an arms race.
People cost money.
Equipment costs money.
What?
You say don't maintain them?
Other villages would laugh themselves to death.
What kind of behavior was that?
A lamb walking up to a wolf and saying,
"I'm a vegetarian. You should be too."
If the wolf doesn't eat you—who would it eat?
What's the most effective way to reduce surplus population?
War.
From the First to the Third Great Ninja War, at their core, they were all driven by resource scarcity.
In Naruto's eyes, ninja—who didn't directly produce resources—were themselves part of the problem.
With the bizarre capabilities of ninjutsu, if ninja were put to work in agriculture, he wouldn't dare promise much—
But food production in this era would definitely double.
Naruto had been pondering this question for a long time:
How did the ninja system even come into being?
Call it a temple like in legends, and yet it meddled constantly in worldly affairs.
Call it a military force trained by nations, and yet the daimyō didn't truly control it.
Most terrifying of all—
It actually survived.
Can you believe that?
And ninja status didn't even seem low.
That was the scary part.
Transcendent, yet not detached from the mundane.
That was Naruto's evaluation of the ninja system.
After thinking it over again and again, the only explanation he could come up with for why ninja survived—and even became a privileged class—
Was chakra.
So, back to the original question:
Had the ninja world ever experienced a period of relative peace?
Yes.
During the reign of the First Hokage.
When the "God of Shinobi," Hashirama Senju, used Wood Style to press every other village into the dirt, the ninja world achieved "peace."
The fuse that ignited the First Great Ninja War was Hashirama's death.
So how do you enter a state of relative peace?
From Naruto's perspective, there were only two ways:
1. Ninja use their killing skills to farm instead—boosting productivity.
2.
Unrealistic. At least not possible for this generation, raised from birth with the mindset of killing.
The next generation… maybe.
2. Create something equivalent to a "super weapon," and enter an alternate-world version of mutually assured destruction.
The peace during Hashirama's era could also be viewed as a form of "nuclear deterrence."
Just replace the "super weapon" with Hashirama Senju himself.
At least in terms of threat level—it fit perfectly.