​The darkness behind the gate seemed to possess mass—heavy, cold, and greedy, swallowing every flicker of light. The lamps on their helmets could only tear small holes in that black veil, creating circles of restless white light that danced to the rhythm of their footsteps. Outside those circles, the world seemed to vanish. There was only a suffocating silence.

​Tack... tack... tack...

​Their footsteps echoed through a stone corridor that had been mute for thousands of years. The walls were rough, filled with primitive manual chisel marks—a stark contrast to the smooth, precision-engineered walls of the deeper levels. Beneath their feet, derelict mine rails lay dormant. The layer of rust was so thick that the bolts had fused with the rock itself.

​Rianor walked at the vanguard, right beside Riven. His eyes narrowed, scanning every shadowed corner caught by his helmet light. He cleared his throat softly, trying to shake the eerie sensation crawling up the back of his neck. He remembered this corridor. He knew every turn by heart. Yet, something was different. Back during the first expedition, their steps felt lighter because they were shrouded in ignorance. Now, the knowledge of the death lurking below made their boots feel as though they were cast in lead. 𝐟𝐫𝕖𝗲𝘄𝚎𝗯𝕟𝐨𝕧𝐞𝚕.𝕔𝕠𝐦

​Arvid suddenly stopped in front of a stone pillar. His eyes, framed by his glasses, widened slightly. "Tsk, look at this..." he murmured, brushing dust off the stone surface. His fingers traced geometric symbols that were nearly flattened by dried moss.

​"These are the early records of Project Legion," Arvid’s voice sounded somewhat hoarse in the silence. "They started digging here. Searching for rare ore veins—Mithril, Adamantite, and... hmm, something called ’Aetherium.’ All of it was for the foundation of their project."

​"Aetherium?" Thorne frowned, his hand reflexively checking the locking mechanism on his Sudrath Spear. "Hah, never heard of it in my life."

​"Neither have I. This is the first time I’ve seen the term," Arvid quickly scribbled something in his notebook. Scritch, scritch. "But if they dug this deep, it means this place was a pure mine before it was repurposed into a military facility."

​Rianor didn’t reply. He kept walking, passing rails that jutted out like giant ribs. His helmet light swept the floor ahead—and suddenly froze.

​"Gulp." A soldier in the back swallowed loudly.

​It wasn’t just one or two. Dozens of human skeletons were scattered along the corridor. Their clothes weren’t gallant battle uniforms, but the rotted remnants of mining overalls. Cracked ancient helmets and rusted pickaxes lay beside skeletal fingers that still clawed at the earth. Their positions were chaotic; some were slumped over, others huddled while covering their heads. They had died in pure terror while trying to flee from something.

​"These aren’t Iron Mercs," Riven’s voice was flat, but a thin breath of relief escaped his nose.

​"The ancient miners." Arvid knelt, observing one skull that had been crushed from the back. "Perhaps they were the first workers who accidentally unearthed ’something’ that should never have been touched."

​Rianor stared at the rows of skeletons with a cold gaze. "Meaning they died even before Project Legion was fully activated."

​"Or they died because the project began, acting as the first sacrifices. Who knows, it’s hard to say for sure," Arvid stood back up, patting the dust off his knees.

​They continued the journey as the atmosphere grew increasingly grim. The corridor began to widen, creating longer echoes. The rails started to branch off, leading to side tunnels that had collapsed and were blocked by rubble. Rianor stayed on the main path that continued to slope downward.

​Then, the sound came.

​Click.

​The synchronized footsteps stopped instantly. Thorne raised his right hand high, giving the absolute signal for silence.

​Click-click. Click-click-click.

​The sound came from the darkness ahead. It wasn’t from one direction; it spread from the walls, the ceiling, and the gaps in the rails. The noise bounced wildly, creating a bizarre symphony that grated on the nerves.

​"Echolocation," Khulafa whispered through the Vibro-Comm. The vibration of his voice felt directly in their ear bones. "I know this pattern. They are mapping our coordinates. They know we’re here."

​Riven pulled the lever on his mechanical axe. Vrooom! The roar of the axe’s engine cut through the silence, drowning out the clicking for a moment. "How many?"

​"A lot. They’re everywhere," Khulafa replied sharply.

​Thorne acted immediately. "Infantry! Semi-circle formation! Spears to the front! Nobody daze off!" Twenty soldiers moved nimbly, the tips of their mechanical spears humming as mana began to flow. Dom and the Ghost Squad climbed a pile of rocks on the left to find a higher firing position.

​Then, they emerged.

​From behind the shadow of a pillar, a creature crawled out with jerky, staccato movements. Its body resembled a human, but its skin was a pale, translucent white, revealing a web of black veins pulsing beneath. There was no hair, no nose, only a wide mouth full of jagged, disorganized teeth. And where the eyes should have been—there was only a thick layer of skin covering empty sockets.

​Mutants.

​One, three, ten... suddenly the walls and ceiling of the corridor seemed to move. They crawled like predatory insects. Their click-clicking turned into hungry snarls. They didn’t see with eyes, but they "saw" the soldiers’ heartbeats through the reflection of sound.

​"Fire!" Thorne’s command exploded.

​Boom! Boom! Zzt!

​Flashes of blue light from the Sudrath Spears sliced through the darkness. Mana-coated slugs slammed into a Mutant leaping from the ceiling, shattering its body into pieces before it even hit the floor. Thick black fluid splattered against the stone walls. However, the other Mutants didn’t retreat. Instead, they crawled faster, lunging without regard for their destroyed kin.

​"Eh, they have no fear at all!" a soldier shouted while keeping his finger on the trigger.

​"They don’t! Keep up the barrage! Give them no openings!" Thorne barked back.

​A Mutant lunged from the shadows, aiming for the throat of a soldier in the front rank. Before its pale claws could touch skin, Riven’s axe cleaved the air. Swoosh! The creature’s body was split perfectly in two, falling to the floor with a disgusting wet sound. Riven moved like a storm; his axe spun, pruning the heads and limbs of any Mutant that tried to draw near.

​"Damn, there are too many of them!" Thorne wiped the sweat that was beginning to pour down his forehead.

​Rianor saw the endless stream of Mutants pouring from the darkness. In an open space like this, they could be surrounded from all directions. "Thorne! Fall back to the narrow gap behind us! Funnel formation!"

​The troops retreated in an orderly fashion. The front rank continued to spit mana rounds while the rear secured the path. Once they entered a passage only wide enough for two men to stand side-by-side, the situation reversed. The Mutants were forced to line up in a single file—easy targets.

​One by one, the Mutants fell, drenched in black fluid. The last one, a larger male, tried to lunge with a hoarse roar. Riven slammed his axe right into the center of the creature’s skull. Crack! A satisfying sound of shattering bone echoed before the massive body slumped lifelessly.

​Silence fell once more.

​Only the sound of heavy panting and the pungent smell of gunpowder mixed with the metallic tang of Mutant fluid filled the air.

​Thorne checked his line quickly. "Three scratches. No fatalities." He turned to Rianor, his chest still heaving. "They’re getting more aggressive. And the numbers... hmm, much higher than what was recorded in the first expedition report."

​"They’re migrating upward," Rianor tucked the Mana Core back into his bag. "Level one used to be relatively clear. Now, they’ve claimed it as a nest."

​Rianor stared at the pile of carcasses before them. Since the main gate was opened years ago, the ecosystem inside seemed to have awakened from a long slumber. Something locked in the lower levels was crawling up, seeking a way out—or seeking fresh meat.

​Arvid suddenly called out from a crevice in the wall hidden behind rubble. "Rianor! Look, there’s something here!"

​Inside the cramped room, an ancient terminal was embedded in the wall. Its screen was a spiderweb of cracks, but a small indicator light still blinked weakly—green... red... green. Like the remnants of a soul refusing to go out.

​Rianor pressed the Sentinel Mana Core to the terminal panel. Zzt... bzzzt... The screen flickered violently before finally displaying rows of ancient text. Arvid’s tablet immediately worked to translate it in real-time.

​"Project approved. We will create a force to combat the Darkness. Code name: PROJECT LEGION. Phase one: core material excavation. Phase two: volunteer recruitment. Phase three:—" The text vanished, replaced by static distortion.

​"Phase three what?" Thorne asked impatiently.

​Arvid shook his head weakly. "Data’s corrupt. But look at the initials at the bottom..." He pointed to the corner of the screen which displayed the name ’A.V.’ "Perhaps this is the project lead."

​Rianor fell silent, absorbing the phrase ’Combat the Darkness.’ Not against neighboring kingdoms, not against humans. There was something far greater that drove this civilization to desperately dig deep into the earth’s belly and create these mechanical monsters.

​"We continue downward," Rianor stood up, his eyes fixed on the corridor that sloped even deeper into the darkness. "This is just the surface."

​They moved again. Behind them, Mutant corpses lay among the rusted rails, becoming new headstones in this old mine. And ahead, the darkness waited with its mouth wide open—thicker, deeper, and perhaps with click-clicking sounds that were far more terrifying.