A heavy silence settled over the group as the sound of movement echoed through the dimly lit corridors. The flickering emergency lights cast elongated shadows on the steel walls, making every shape seem like something lurking in the dark.

Leon tightened his grip on his weapon, his electricity crackling faintly at his fingertips. His senses were heightened, his instincts screaming that something was watching them.

Eric adjusted his stance, his shotgun raised. “I don’t like this. At all.”

Carter’s fingers flew over the control panel, rapidly downloading as much data as he could. “Just a few more minutes,” he muttered.

Leon nodded but kept his eyes locked on the doorway. He felt it before he saw it—a presence, wrong and twisted, slithering in the darkness.

Then, the corridor’s lights flashed violently, and something moved at unnatural speed.

A blurred shadow lunged from the hallway, too fast, too sudden. Leon barely had time to react before a monstrous claw swung toward him.

He twisted, narrowly dodging the strike. Steel tore like paper as the creature’s claws ripped through a reinforced wall.

Eric fired immediately, his shotgun’s blast illuminating the corridor, but the thing was already gone, retreating into the shadows.

“What the hell was that?!” Eric shouted.

Leon’s heart pounded. His enhanced vision caught glimpses of twisted, sinewy muscle, elongated limbs, and multiple eyes that reflected the red emergency lights.

Carter paled. “That… that thing isn’t a normal mutant.”

Leon’s mind raced. Whatever this was, it was faster, stronger, and unlike anything they had faced before.

A low, guttural clicking filled the air, a predator’s sound, a mockery of speech.

Then, the emergency lights flickered out completely.

Total blackness swallowed them.

Leon’s breathing steadied as he adjusted to the absence of light. His new abilities made him more sensitive to electrical signals, and he could feel traces of movement through the facility’s failing power grid.

“It’s still here,” Leon whispered.

Eric cursed under his breath. “Great. Fighting a nightmare in the dark. Just what I wanted.”

Leon inhaled deeply, then let the electricity inside him surge.

A bright arc of lightning erupted from his hand, crackling across the room, illuminating the area for a brief moment. The creature was on the ceiling, twisted into an unnatural position, its multi-eyed gaze locked onto them.

It dropped.

Leon threw himself forward, unleashing a wave of electricity that blasted through the air, slamming into the creature mid-fall. The room flared with white-hot energy, and the scent of burnt flesh filled the air.

The mutant screeched, a horrific mix of inhuman wails and static-like distortion, before retreating once more into the depths of the facility.

Leon panted, his hands still crackling with residual lightning.

Carter’s voice was tight. “That thing’s learning. It retreated because it knows you’re dangerous.”

Leon exhaled, eyes scanning the darkness. “Then we don’t give it time to strike again.”

Something was happening to him. Ever since absorbing the last core, his power had evolved. He didn’t just generate electricity now, he could sense electrical currents, even in the biological impulses of living creatures.

He closed his eyes for a moment. The air felt charged, alive with unseen patterns of energy flow. The Blackwood Facility wasn’t just holding secrets, it was feeding him something new.

Eric’s voice pulled him back. “We need to move. Now.”

Leon nodded. “Carter, did you get the data?”

Carter hesitated before holding up a small drive. “Everything that was left.”

“Then we’re done here.”

As they turned toward the exit, a low mechanical hum resonated through the facility, an artificial voice echoed from the intercom, its tone eerily calm.

"Blackwood Protocols Activated. Security Measures Engaged."

Then, a series of distant metallic clangs reverberated through the halls.

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Doors were locking.

Traps were activating.

And something deep below was waking up.

***

A deep mechanical hum vibrated through the floor beneath them, resonating through the reinforced steel walls of the Blackwood Facility. The sterile corridors, once abandoned and silent, were now alive with unseen danger.

"Blackwood Protocols Activated. Security Measures Engaged."

The robotic voice echoed once more through the speakers, followed by the distant sound of metallic locks slamming shut.

Leon’s eyes darted to the control panel next to Carter. The screen flickered with red warnings:

LOCKDOWN INITIATED

FAILSAFE SYSTEM ENGAGED

BIO-CONTAINMENT PROTOCOL 13: ACTIVATED

The last one sent a cold chill down his spine.

“Bio-containment?” Eric muttered. “I don’t like the sound of that.”

Carter swallowed hard, typing frantically. “They must have left behind some… defenses. We need to move before...”

The facility shuddered violently, cutting him off.

Then, from deep below, something roared.

Leon moved first. “We need a new exit. Now.”

Carter nodded, scrolling through the terminal, his fingers flying across the screen. “Shit! our original exit is sealed tight. The only way out is through a maintenance shaft two levels down.”

Leon exhaled sharply. “Then we go down.”

The group sprinted through the corridor, their boots echoing against the metallic flooring. Emergency lights flashed ominously, casting moving shadows along the walls.

A sudden hiss of compressed air released from a nearby vent, and then...

THUD.

Something huge landed behind them.

Leon spun around, electricity crackling in his hands.

What stood before them was not human.

It was heavily mutated, its muscles stretched grotesquely, covered in a chitinous, blackened shell that pulsed with a sickly glow. Its face was distorted, a twisted fusion of a skull-like structure and pulsating veins.

Leon’s instincts screamed, this was a Bio-Containment Subject.

It wasn’t just a mutant. It was something engineered.

The creature’s multi-jointed limbs tensed, and then it launched forward with terrifying speed.

Leon reacted instantly, raising his hand. A massive bolt of lightning arced toward the creature, striking it directly in the chest. The energy surged through its body, lighting up its veins like a network of burning wires.

The mutant shrieked, momentarily stunned.

Eric didn’t waste time, he raised his shotgun and fired directly into its exposed head.

The blast tore through its skull, sending chunks of blackened flesh flying across the walls.

For a moment, silence.

Then, the creature twitched.

Before their eyes, its wounds began to close, tendrils of flesh knitting back together unnaturally fast.

Leon cursed under his breath. “Regeneration.”

The monster lurched forward again.

Leon didn’t hesitate, he reached deep within himself, feeling the new core he had absorbed shift inside his body. It was different from before. Stronger.

Electricity surged through his veins, but this time, it wasn’t just a simple discharge.

He clenched his fists, and the metallic walls around them shook violently, drawn to the energy he was radiating.

Then, a shockwave exploded outward.

A massive electromagnetic pulse surged through the hallway, shutting down the flickering emergency lights and frying the security sensors.

But more importantly, the creature staggered, its biological functions thrown into chaos.

It screamed, its body convulsing violently.

Leon felt it then, his power didn’t just control electricity. It could disrupt nervous systems.

“Now!” he shouted.

Eric took the cue, unloading two consecutive shotgun blasts into the mutant’s skull.

This time, its regeneration failed.

The creature collapsed, twitching one final time before going completely still.

Breathing heavily, Leon turned to Carter. “Find that shaft. Now.”

Carter, still wide-eyed from the battle, nodded and ran toward the nearest access panel. A few keystrokes later, he pointed toward a hidden hatch on the floor.

“There! This will take us straight to the lower levels.”

Leon and Eric pried open the heavy hatch, revealing a dark maintenance shaft leading downward.

The air below was thick, carrying a strange chemical stench.

Leon took one last glance at the mutated corpse behind them.

Something was very wrong with this place.

And they were about to go deeper into the heart of it.

Leon took a deep breath, his pulse still racing from the fight. The stench of burned flesh and ozone filled the air, remnants of his electricity tearing through the mutated creature. But they couldn’t stay here, whatever had infected this facility was far from over.

“Let’s move,” he said, gripping the edge of the hatch.

Eric slid down first, disappearing into the darkness below. Dr. Carter hesitated for a moment before following. Leon took one last glance at the corridor, the flickering lights casting eerie shadows over the corpse.

Then—he felt it.

A presence.

The hair on his arms stood up as a strange vibration rippled through the air, as if something was watching from just beyond his vision.

Then, the mutant’s body twitched.

Leon’s heart nearly stopped.

But instead of regenerating, it dissolved.

The blackened flesh bubbled and melted, sinking into the floor like liquid shadow, the veins pulsing one last time before the entire body was gone.

No remains. No trace.

Leon clenched his jaw. That’s not normal.

And then—a whisper.

It was distant, like a sound carried by the wind, but it wasn’t the facility’s speakers. It wasn’t the security system.

It was… something else.

"You are not ready."

Leon’s breath caught in his throat. The voice wasn’t coming from his ears. It was in his mind.

"Not yet... but soon."

A sudden clang echoed down the hallway, as if something massive had just shifted in the darkness beyond.

Leon didn’t stick around to find out. He dropped into the shaft, slamming the hatch shut above him.

The descent was steep. The air grew heavier, filled with an unidentifiable chemical scent, mixed with the dampness of old, stagnant air.

Leon hit the ground with a soft thud, landing in a dimly lit maintenance tunnel. The walls were lined with exposed pipes and rusting metal panels, the infrastructure far older than the upper levels.

Eric stood near a junction, shotgun raised, while Carter frantically typed into a portable console.

“This place is…” Carter trailed off, eyes scanning the ancient metal beams. “This wasn’t part of the Blackwood Facility’s original design.”

Leon frowned. “What do you mean?”

Carter swallowed, his voice dropping to a whisper.

“I think this place is older than the facility itself.”

A chill crept down Leon’s spine.

Then, a deep, guttural growl rumbled from the tunnel ahead.

Eric tensed. “Tell me that was the pipes.”

Leon shook his head.

It wasn’t.

A slow, deliberate scraping noise echoed through the corridor, like something with claws dragging against metal.

Then, footsteps.

But they weren’t human.

Leon took a step forward, eyes narrowing into the darkness ahead. His body thrummed with energy, power coiling at his fingertips.

Whatever was down here wasn’t a mutant.

It was something else.

Something waiting for them.

And it knew they were coming.