The reactor's fiery cataclysm still scarred everyone's memory. The column of fire that had devoured the heavens kilometers from Konoha had left behind not only scorched earth, but a silence heavy with questions and suspicion. Minato had ordered a reinforcement of vigilance on all borders, and the clan leaders remained on edge, as if at any moment an external threat might emerge from the void.
But for me, that was not an end. It was a beginning. Failure is the foundation of great discovery, and I knew that better than anyone. The mistake wasn't in attempting the impossible, but in choosing a location too close to the village. If we were to build an artificial sun, this time we would do it in an even more secluded place, where there was no risk that the Hidden Leaf Village would pay the price for our ambition.
We chose a desolate valley, surrounded by black rock mountains with a river twisting like a silver serpent at its base. There, hidden from the eyes of any traveler, we began to build our new research base.
Renji had transformed an ancient cave into a makeshift workshop. From the outside, you could barely make out an opening between the rocks, but within reigned a world of metal, fire, and symbols etched into every surface. In the center of the cavern, long work tables were covered in scrolls, blueprints with unfinished calculations, and dozens of metal tools. The smoke from the charcoal and the glow of the furnaces gave the place the appearance of an ancestral forge, but the seals etched into every wall made it clear that this was a ninja workshop, a place where science and chakra merged into one.
Renji, his hair tied back haphazardly and his hands stained with soot, moved among the workbenches like an tireless alchemist. He had spent weeks improving the seals that regulated chakra consumption. The great flaw of the previous experiment had been the absurd amount of energy the reactor demanded, draining our reserves in a matter of minutes. Now, every symbol was being re-imagined: simpler strokes, better-distributed flows, connections that resembled electrical circuits, but carved with precision into parchment and metal.
As he concentrated on the designs, my clones worked without rest. One group hauled enormous steel beams that we had forged in makeshift furnaces, reinforced with runes of heat. Others hammered incandescent plates on stone anvils, while a third group dedicated themselves to cooling the metal with water jutsus, forging structures that looked like the colossal bones of a metallic giant. The echo of the hammer strikes resounded in the cavern, mingling with the roar of the fire and the hiss of steam.
Each beam was embedded with copper inlays, where the coils that would generate the magnetic fields would later be placed. The clones moved with the precision of a coordinated swarm: some transported the burning ingots from the furnace, others held them with reinforcing seals so they wouldn't deform, and the most skilled meticulously etched the symbols that would later channel the chakra.
The sight was hypnotic. Dozens of myself repeating tasks impossible for a single person: lifting, forging, cooling, etching. Renji's workshop had transformed into a pulsating heart of effort, where every movement was aimed at raising the collapsed dream from its ashes.
Renji, without taking his eyes off a scroll where he was correcting lines and equations, muttered to himself: "The problem isn't power… it's efficiency. A seal must work like a perfect machine, without leaks, without excess. If we can make each symbol consume half the chakra, the reactor can sustain itself twice as long…"
I listened to him in silence, satisfied. That boy who once only dabbled in theory had now become my right hand. He didn't need orders; his mind ran as fast as mine, and at times even reached solutions I hadn't considered.
The air inside the cave was charged with smoke and electricity. Every time a seal was finished etching into the metal, a blue spark ran across the surface, as if the chakra itself approved of its existence. And although my clones sweated in the suffocating heat, none of them stopped. We all shared the same certainty: from these ruins, something greater would be born.
It was no longer just the dream of a spacecraft, or the whim of playing with the stars. It was the challenge of proving that the will of fire could give life to the impossible, even if it meant building a new sun in the midst of the mountains.
The echo of the hammer strikes still resonated in my mind when I decided to leave the workshop. The clones continued working on the beams, the fire roared inside the furnaces, and Renji, engrossed in his scrolls, didn't need my immediate attention. It was a good time to do something different: visit my brother.
Sasuke had just turned three. Time had passed too quickly since I saw him take his first stumbling steps. Now he ran through the house's hallways with inexhaustible energy, and although he was still a child, there was something about him that set him apart from the rest: a gleam in his eyes, an intensity that seemed to overflow from even the mundane.
When I found him, he was in the backyard, with a small bowl of water in front of him and his hands forming seals that were clumsy but surprisingly precise for his age. I stopped in silence, leaning against the shade of a tree, and watched him.
"Katon!" he exclaimed, and a flicker of fire erupted from his mouth, small and hesitant, but real. The water in the bowl rippled with the heat, giving off steam. Sasuke stared at the result, first surprised, then smiling with that proud expression that always reminded me of Father.
I approached him slowly. "Not bad…" I said, and he started, as if he had been caught stealing sweets.
"Nii-san!" he ran toward me, his brow furrowed and his forehead smudged with soot. "It almost came out just like I practiced!"
I knelt in front of him, placing my hand on his shoulder. "Almost, huh? For a three-year-old, that's more than enough. At your age, I could barely maintain a steady flame…"
Sasuke looked up, confused. "Really? You were weaker than me?"
I laughed softly. "It's not weakness, it's time. Each person has their own path… But yes, at your age, I couldn't do what you just did."
I saw him bite his lip, as if trying to process the idea of being "better" than his older brother at something. However, the spark of determination in his eyes confirmed it for me: he would take it as a challenge, as an even higher goal to reach.
He sat down on the ground again and began to form seals once more, his small fingers fumbling with the positions but moving forward without stopping. This time, instead of fire, he was trying to channel chakra into his feet. The result was clumsy, but enough to kick up dust as he jumped higher than normal.
"Look, Nii-san, I can do it!"
I watched him with a mixture of pride and a pang of unease. It wasn't normal. At three years old, Sasuke already had a grasp of basic chakra control, could generate fire, and, most surprisingly, had energy reserves superior to what I remembered myself having at his age. It was as if an inexhaustible source resided within him.
"Sasuke," I said in a low voice. "Never forget that chakra isn't just power. It's life. Controlling it is a responsibility, not just glory."
He nodded with the seriousness that only a child who doesn't fully understand can show, before laughing again and launching another small jet of fire into the sky.
As I watched him play, I understood something: my projects, my reactors, my dreams of traveling between dimensions… all of it had a deeper purpose, and I had to share it with my loved ones, not walk the entire path alone.
That thought embedded itself in my mind like a silent promise: rising from the ashes wasn't just about rebuilding an experiment—it was about preparing the future for my brother and for all who would come after.