The search mission was a massive drain on our system resources. We'd been scouring Area B-7 for days, finding nothing but weathered rock, eternal dunes, and the kind of "nothingness" that makes you start doubting your own sensors. Fatigue was setting in, and even Captain Iryō's beast-like intuition was hitting a wall.
We were moving along a dried-up ancient riverbed, a corner of the Land of Wind that felt like it had been deleted from the map centuries ago. The rock pillars here were twisted by wind-erosion into bizarre, jagged shapes.
"This sector is a graveyard," Lucado complained, tapping his kunai against an iron-hard rock wall. "Are we even looking for a person anymore? Or just an excuse to stay away from the village?"
"Follow orders and keep your mouth shut," Iryō snapped, but his brow was furrowed. The environment was harsh even for Suna standards.
"I'll broaden the scan," I said, stepping forward.
I deployed three Spider MK 2s. In this complex terrain, they were far more efficient than a human search party. I controlled them like a cluster of agile drones, sending them deep into the crisscrossing rock fissures and underground caves. I was receiving three simultaneous feeds of high-resolution terrain data.
For hours, it was just more of the same: dust, cave-crickets, and animal skeletons. Then, the Spider in the deepest fissure hit an anomaly.
It wasn't a visual ping. It was an energy fluctuation, a signal so pure and ancient that it felt like an "out-of-band" transmission. It wasn't the messy, attribute-heavy chakra I was used to; it carried an unspeakable sense of gravity, like a piece of the world's original source code.
My heart skipped a beat. I focused all my processing power on that single Spider's feed. At the end of a narrow, lightless crack, half-buried in the silt, was a small, irregular fragment. It wasn't metal, and it wasn't wood. It was dark, its surface naturally etched with patterns so complex they made my sealing runes look like finger-painting.
"Find something?" Iryō asked, noticing my pause.
I ran a quick risk-assessment. This energy was too "loud." If I exposed it now, the village High Command would take it, study it, and I'd never see it again. I needed this for my own "Body Tempering" project.
"Nothing," I said, my voice as flat as a pre-recorded message. "The fissure is a dead end. Just some weird mineral density in the rocks. The Spider can't get through."
Iryō gave me a scrutinizing look, probably sensing a minor lag in my response, but he ultimately chose to trust the kid who saved his life. "Continue the sweep elsewhere."
Secretly, I navigated the Spider. Its slender forelimbs dug the fragment out of the sand, securing it against its abdomen. I quietly maneuvered the puppet back to my pack, hiding the "Unknown Fragment" in a lead-lined compartment I'd built for poisoned needles.
My heart was hammering. I knew I'd just picked up a piece of the "Legacy System."
That night, while the squad camped in a cave, I waited for the others to hit Sleep Mode. Once I was sure Iryō was focused on the perimeter, I retreated into a dark corner and pulled out the fragment.
Holding it, the sensation was overwhelming. It wasn't violent; it was deep. It felt like I was holding a "World Battery." My affinity for Natural Energy, the stuff the monks at the temple whispered about, seemed to spike just by being near it.
What is this?
I thought back to Shukaku's incoherent screaming inside my head: "The woman from outside the heavens! Ōtsutsuki Kaguya! She planted a damned tree... the tree that drank the world!"
Ancient secrets. The Divine Tree. The war between Kaguya and the Sage of Six Paths.
Was this a fragment of the original "Server"? A piece of the Divine Tree that had once devoured the planet's energy? If it was, the value was incalculable. This wasn't just "fuel." This was the key to moving my Body Tempering Furnace from "Chakra-level" to "Natural Energy-level."
I carefully wrapped the fragment in a specialized sealing scroll, isolating the signal. This was my "Zero-Day" discovery. Until I had the power to protect it, this was a secret I'd take to the grave.
I looked out at the stars through the cave entrance. We were out here looking for a missing Kazekage, and I'd stumbled onto something that might have predated the Hidden Sand itself.
The search mission was a failure for the village, but for Sayo the Engineer, it was the ultimate upgrade.