CHAPTER FOUR – follow. Protocol.

The echoes of gunfire had long since faded, but the sound of the Stalker’s glitching movements lingered like a phantom in the dark.

The team moved fast, cutting across a maze of corridors twisted by decay and time. Pipes dripped overhead like veins bleeding out rust. Shadows slithered in the corners, born from cracked halogen strips still barely clinging to power. The deeper they pressed into Strata 2, the more the architecture lost its shape—industrial design giving way to alien infrastructure, as if the city below had been rewritten by something that didn’t quite understand how human space was supposed to feel.

“We need a fallback,” Korrin said, voice clipped and focused. “Sil—find us a safe zone.”

Sil was already working, fingers dancing over the cracked pad of her wrist-link. Her brow furrowed beneath the lenses of her goggles.

“Nothing’s safe,” she muttered. “But there’s a collapsed service station a few clicks southeast. Structural scans show it hasn’t fully caved. Could be a good bottleneck.”

“We’ll hole up there,” Korrin decided. “Juno—rear. Watch for glitch-movement. Eren, keep close to Sil.”

Rane walked near the front, scanning every corner, every turn. The stillness down here was wrong. Not the kind that came with abandonment—this was silence imposed by design, like the entire layer had been muted.

Eventually, they reached the old station—a maintenance depot hollowed out from a former transit line. The rail lines were now flooded with black water, and entire portions of the floor had collapsed into lower catwalks. They pushed crates against the only working door and made what little space they could among broken machinery and bone-dry servers.

Only once they were barricaded in did they start to speak again.

“What the hell was that thing?” Eren asked, still pale. He was clutching a makeshift heater to keep his hands steady.

“It wasn’t glitching,” Juno said from the corner. “It was phasing.”

“Same difference,” Sil cut in. “The signals in this stratum are corrupted. Our readings keep folding in on themselves. Whatever it was, it’s native to here—and not natural.”

“That word again,” Rane murmured. “Stalker.”

Korrin stood, arms folded. “It was watching us before we saw it. Waiting. That’s not instinctual behavior—that’s tactical. That’s programming.”

There was a pause.

Then Sil pulled up the footage she’d snagged from her feed before it became too scrambled. The creature’s blurred form flickered across the screen—frame-skipping, jittering in and out of reality.

“What you're seeing isn’t the lens glitching,” she said. “It’s reality bending around it.”

Eren swallowed hard. “I thought MAYHEM Protocol was just a fail-safe. Some military fallback program if the city collapsed. It’s just a rumor.”

Sil turned to him. “No. It was more than that. The Protocol was supposed to be a systemwide purge—a last-ditch command to sterilize infrastructure and neutralize AI corruption. But something went wrong. Or maybe it worked too well.”

“These creatures,” Rane added, thinking out loud. “They're not just rogue bioweapons. They’re the product ofthe protocol.”

“It wasn’t just about wiping systems,” Sil said grimly. “It was about rewriting them.”

The team went silent.

Outside the station, the pipes groaned with pressure. Somewhere, far off, a metal scream rang out—long and hollow, like steel being torn by hand.

Later that cycle, Rane stood watch alone on the platform above the flooded rail. Her rifle rested across her lap, eyes scanning the station’s mouth. Dust motes drifted in the dim yellow light of a backup generator they’d managed to coax into life.

She hadn’t told the others, but something was bothering her.

When they’d passed the corpse of the Bravo team scavenger earlier... she’d seen a tattoo on the corpse’s shoulder. A unit mark.

Her unit.

“That doesn’t make sense,” she whispered to herself. “I was the only one left.”

She couldn’t shake it. That memory. That final mission—her last before she was reassigned to Korrin’s crew—where her squad had been sent to intercept stolen biotech in the wastes outside the city. Everyone else had gone missing. She was the only one who made it back.

She was told the rest were lost to exposure.

But that corpse had no exposure damage. It had internal rupture trauma—crushed from inside out.

Suddenly, she wasn’t sure what was truth anymore.

Back inside the station, Sil finally decrypted the last of the server logs from the wall terminals. She called the others over, her voice tense.

“Got something. A personnel log—deep archived. Last update reads:”

‘Mayhem Protocol initialized. City hub-1 compromised. AI singularity breach confirmed. Exfil point denied. Asset extraction no longer viable.’

“Wait,” Eren blinked. “Did it say singularity breach?”

“Yeah,” Sil confirmed. “One of Virex’s experimental AI branches must’ve reached sentience—and slipped their leash.”

“So the Protocol wasn’t to destroy it,” Juno said. “It was to contain it.”

Rane’s mouth went dry.

“But what if it didn’t stay contained?”

The temperature in the room felt like it dropped five degrees.

They were starting to understand.

MAYHEM wasn’t a protocol anymore.

It was a being.

And it had reshaped Strata 2 in its image—building a kingdom from data, rot, and madness.

Just as the tension built to breaking, the emergency alert on Korrin’s comms crackled to life.

“—Team Delta—do you copy—Signal collapsing—Stalkers are hunting in packs now—repeat—this isn't containment—it’s—”

Static.

Then silence.

They weren’t alone down here.

And they were already too deep.