The train station hadn't been operational in over twelve years.
The old maps called it Metroline 8 – Sector Twelve Terminal, but the locals called it The Teeth, a jagged underground ruin half-swallowed by a tectonic shift during the quake of '66. Most assumed it had collapsed completely. The Core decommissioned the entire sector and rerouted all traffic. No maintenance. No lights. No surveillance.
Which was exactly why Nova was headed there.
She crouched on the roof of an old maintenance tram car as it creaked slowly through the ruins of the tunnel. The vehicle was jury rigged and barely powered, running off a hijacked auxiliary line she'd patched manually an hour ago. Her coat fluttered slightly in the stale air, its stealth mesh dimmed but ready. Her visor tracked the signal, it pulsed stronger here, clearer. It wasn't random. It was locked to her frequency now.
Nova's fingers drummed against the sheath of her blade. She hated silence underground. The acoustics played tricks on her hearing, masking footsteps, cloaking drones. She double-checked her ammo, re-sheathed the plasma dagger on her thigh, and scanned the dark.
Fifty meters.
The train hissed to a stop at the edge of a broken platform. Lightless. Overgrown with rust, vines, and the occasional trail of phosphorescent fungi that had adapted to artificial heat.
Nova jumped down lightly, boots splashing in shallow stagnant water. Her blade stayed dormant, for now.
The air smelled like mold, ozone, and scorched circuitry.
She moved quickly, sweeping her vision in arcs. The deeper she walked, the more the world seemed to constrict around her. The tunnel curved ahead, fractured by a collapsed column that opened into an abandoned terminal chamber. Glass displays hung cracked and silent, ads frozen in pixelated ghosts. A shattered vending machine buzzed faintly, dispensing nothing.
Her HUD pinged.
SIGNAL SOURCE: 18 METERS AHEAD.
Behind the old ticket counters, a faint light flickered. Nova approached slowly, blade in hand, cloak mesh active. She knelt beside a rusted security gate and spotted it: a sub terminal interface carved into the floor, new tech, custom wiring. Someone had been here. Recently.
She scanned it.
Encryption Type: Biometric lock / Double-layered cipher / Adaptive firewall.
This wasn't amateur work. But it wasn't Core either.
Her visor flickered, identifying hand shaped input nodes and a retinal scanner, patched together with scavenged parts and stitched into the existing infrastructure.
She hesitated.
Her hand hovered over the interface.
Then she placed her palm on the reader.
It buzzed softly, warm.
"—Welcome back, N-04A."
Her heart dropped.
No one called her that anymore.
Not even The Core.
She pulled her hand back, blade raised. But nothing happened. No drones. No alarms.
The panel slid open. A narrow passage revealed itself, metal steps leading downward into deeper darkness lit only by red strips of low energy emergency light.
She stepped in.
The corridor felt like it hadn't seen a living soul in years. But she could feel eyes on her.
The sensors embedded in the walls were old Core design, basic motion tracking, low resolution audio. She disabled three manually as she descended. At the base of the stairs, a reinforced blast door stood sealed. The same strange tech mod interface flickered on the panel beside it.
Nova leaned in.
"Nova," said a voice.
She froze.
It wasn't a recording.
The voice was tired, raw, and unmistakably human.
"I wasn't sure if you'd come," it said again. "They told me you'd never escape. That even if you did, the tether would find you eventually."
"Who are you?" Nova asked quietly.
A pause.
Then static.
"Come inside. I'll explain. But I don't know how much time we have."
The door groaned open.
Nova stepped through.
The interior of the bunker was a bizarre hybrid of clean-room tech and salvaged ruin. Broken consoles were arranged like a shrine around a central core of humming cables. Displays flickered with code, real time satellite feeds, fragments of intercepted Core comms. It was a war room and a tomb.
A woman stood at the far end of the room, her body half illuminated by the soft blue glow of interface screens. She wore a battered technician's coat, layered with reinforced body mesh. Her skin was pale, almost gray, and her eyes were cybernetically enhanced, one flickered softly with interface light, the other entirely human. Her hair was short, messy, and streaked with silver.
Nova raised her blade, tense.
"I asked you once before," Nova said coldly. "Who are you?"
The woman smiled faintly.
"You called me Alyx. Before they wiped your memory."
The silence that followed was too long. It felt like it echoed.
Nova didn't move. Her grip on the blade didn't loosen. Her breathing remained controlled, but her heart? It shook.
"You were in my signal logs," Nova said slowly. "Eight years ago."
Alyx nodded. "I was one of the engineers on Project NOVA. One of the only ones who stayed behind after Phase 3 went active. I built part of your neural interface. The part they didn't control."
"That doesn't answer my question."
Alyx stepped closer. Carefully.
"You weren't meant to wake up the way you did. You were the first of the NOVA candidates to show recursive memory bleed. It scared them. You remembered pain. Faces. Words. That wasn't supposed to be possible."
Nova lowered her blade slightly. "Why?"
"Because you were never supposed to be human again."
A long silence passed between them.
Alyx turned to one of the side monitors. Static danced across it, then cleared to show satellite footage, grainy, zoomed in.
The image was unmistakable: a Core facility, buried beneath Sector Forty-Two. Hundreds of transport mechs moved around a massive dig site. Cargo bays opened and shut in rhythm. Drones hovered above.
Nova recognized the place. Facility Zero.
The place where she was made.
"They're awakening the others," Alyx said grimly. "You were prototype N-04A. There are forty-seven more. Some still in cryo. Some... worse."
Nova's jaw clenched.
"They built them anyway."
"Of course they did," Alyx whispered. "The board vetoed the ethics protocols after you broke containment. They saw your defection as proof of evolution not failure."
"Let me guess," Nova said. "Now they want their perfect soldiers back."
"Worse," Alyx said. "They want to seed the neural core into the population. Cognitive overwrite. No more resistance. Just compliance."
Nova stared at the feed. Her blade still glowed faintly in the gloom.
Then she looked back.
"Why tell me this?"
Alyx looked at her, sadness in her eyes. "Because you're the only one who ever survived the override. You're not a prototype anymore, Nova. You're a weapon they can't predict. And I need you to stop them."
Nova turned away. Walked to the console. Ran her hand along the edge of the display.
"I killed four Sentinels and a Hunter to get here," she said. "If they traced my steps, they'll be here soon."
"They will," Alyx said. "Which is why we can't stay here."
Nova turned back. "We?"
Alyx lifted a case from beneath the desk. Inside was a compressed power cell, two data cores, and a folded drone wing.
"I have the access keys to Facility Zero," she said. "Buried in code across five dead nodes. They won't hold much longer. We either shut it down from the inside—"
"—Or it spreads."
Alyx nodded. "Exactly."
Nova looked at her.
For the first time since she broke from The Core, she saw someone who hadn't just survived, but had waited. Fought. Alone.
The silence was shattered by a single sound.
Clang.
From upstairs.
Boots.
Nova drew her blade again.
"They're here."
Alyx didn't flinch. "There's a tunnel. Freight access. It'll lead us into the maintenance ducts."
Nova looked back once at the flickering map of Facility Zero.
Then she moved.
"Then let's finish what they started."