The tunnels swallowed him.
Naruto limped through darkness that felt too still, too silent. The System in his head pulsed low and slow now, no longer whispering urgent data — just a steady hum, like a heartbeat in sync with his own.
His body ached. Every breath dragged fire through his ribs. Blood matted the side of his face and dripped from his fingertips, but he didn't stop.
Stopping meant dying.
He didn't know how far the corrupted Sasuke's reach extended, or what kind of surveillance this broken version of Konoha had, but something in his gut told him he was off the radar now. The deeper he moved into the underground, the colder the air became, and the more the static in his head cleared.
The System went quiet.
That's when he knew.
He had crossed into somewhere different.
A place not bound by the same rules.
A dead zone.
Not just chakra-dead. Data-dead.
The tunnels leveled out and opened into a cavern so wide he couldn't see the other side. Strange roots glowed faintly along the walls, casting dim violet light across a field of old debris — broken weapons, cracked ANBU masks, torn banners with the old Fire symbol.
It was like walking through a graveyard of forgotten wars.
Naruto stepped carefully, heart still thundering. His eyes scanned the shapes in the distance — ruins of old tech, shattered summoning scrolls, even chunks of what looked like Uchiha armor embedded in the dirt.
Then a voice rang out.
"Don't move."
It wasn't loud. It didn't have to be.
Naruto froze.
A figure stepped out from behind one of the massive stalagmites. Cloaked in tattered brown, face hidden beneath a cracked porcelain fox mask. They moved without noise — no chakra signature, no presence.
Like a shadow that had never belonged to the world above.
"I don't know what kind of freak you are," the masked figure said calmly, "but if you dragged the Phantoms down here, I'll gut you before they reach the breach."
Naruto raised his hands slowly, even though he could barely keep them steady. "No Phantoms. Just me."
The masked figure stared.
Then, without warning, they vanished.
Naruto ducked, but it was too late — a cold blade pressed against his throat from behind.
"Who sent you?" the voice hissed.
"No one," Naruto gritted. "I'm not even supposed to be in this world."
Silence.
Then the blade pulled back slightly.
"Turn around. Slowly."
Naruto obeyed. The figure stood directly in front of him now, mask cracked diagonally, revealing a single eye — scarred and tired, but sharp.
"You're not lying," they murmured. "Your signature… it's broken. Glitched."
"I was attacked," Naruto said, voice rasping. "By someone who looked like Sasuke. But… different. Like his chakra was rewritten."
The masked figure went stiff.
"Name."
"Uzumaki Naruto."
A pause.
Then the blade lowered completely.
"Impossible," the figure whispered. "They said you were deleted during the Cataclysm. That you were erased from the root code."
"I guess I'm hard to delete," Naruto muttered.
The figure hesitated, then reached up and removed their mask.
Naruto's breath caught.
It was a girl — maybe seventeen, with jet-black hair cropped short and a single red stripe slashing through it. Her eyes were sharp, green, and ringed with digital fragments like broken glass.
She looked like someone born from the system but severed from it.
"My name's Kai," she said. "And if you really are who you say you are… you're either the key to fixing this world — or the final bug that breaks it beyond repair."
She gestured for him to follow.
He didn't argue.
Kai led him through a maze of ancient tech, down corridors carved into the bones of the earth. Naruto saw databanks melted into stone, half-dead summoning circles crackling with corrupted seals, and even what looked like pieces of old Hokage artifacts half-sunken into dust.
"This is the Undergrid," Kai said without turning. "The last place the Throne System can't see."
"Throne System?" Naruto echoed.
Kai stopped at a wide control panel that buzzed softly, its screens flickering with corrupted feed — looping footage of destroyed villages, screaming jutsu users, and glitching shinobi dissolving mid-combat.
"The system that governs everything now. Chakra, time, reality. The corrupted Sasuke you saw? He's a Phantom. One of the Throne's Executions."
Naruto's throat tightened. "He said I was the Null Code. That I was the last mistake the old world made."
Kai turned to him, face pale.
"Then it's true. You were supposed to be the root variable that balanced the shinobi world… until the reboot."
She pointed at one of the cracked monitors. It showed a still image — a moment frozen in time — of Naruto standing atop the old Hokage building, cloak billowing, eyes fierce.
The Seventh Hokage.
"I don't remember this," Naruto whispered.
"That's because this timeline isn't your own," Kai said. "You were extracted. Fragmented. Rewritten."
Naruto swallowed hard.
"So what the hell am I supposed to do?"
Kai's expression darkened.
"Break the Throne."
The screens around them began to glitch faster, warning signs flaring in red.
[WARNING: Data Disruption Detected]
[Phantom Signatures Incoming - Sector Echo]
Kai drew a long dagger from her side and spun it once.
"They found us," she said.
Naruto clenched his fists, the system humming faintly to life again.
Then bring it on, he thought.
If this dead zone was the last place the Throne couldn't touch…
He was going to make damn sure it was where the rebellion began.