Captain Danu’s tactical flashlight cast a sharp reflection across the ancient mechanical relief sculptures carved neatly into the tunnel's red brick walls. The rhythmic echo of dripping water fell at a sluggish, monotonous pace, magnifying the crushing silence blanketing the fleeing group.

Zulfa brought his face close to the wall's surface, studying the intricate gear and geometric energy-wave carvings with intense focus. "These mechanical patterns are hyper-precise," Zulfa murmured quietly, his fingers tracing the cold, grooved lines of the stone. "Even with modern lathe machinery today, carving something this small and symmetrical inside an underground cavern without electricity is nearly impossible."

"Meaning the primordial civilization that built this place possessed an engineering mastery far surpassing anything recorded in the city's official history," Naya chimed in, stepping closer to Zulfa while brandishing her mini flashlight. She cast her light toward the bottom of the wall, where the stone tunnel floor was blanketed by a thick layer of brownish-tan dust. "Still, Zul... look down at the floor beneath us. There's something there."

Zulfa shifted his gaze downward. Captain Danu instantly swept his flashlight beam across the dusty floor surface as well.

Atop the expanse of ancient dust untouched for centuries lay a set of sharply defined, freshly pressed footprints. Yet what made their skin crawl wasn't simply the presence of footprints in this remote expanse, but the bizarre shape of those tracks.

Their size dwarfed a normal human foot—nearly twice the length of a military combat boot—featuring a three-toed claw imprint biting deep into the dust layers.

Roni, one of the resistance fighters, swallowed hard, gripping his rifle barrel tighter. "Wait... those... those aren't human footprints, are they? Their shape is completely unnatural!" he whispered tautly, his eyes darting wildly into the tunnel darkness ahead.

"Obviously not human," Captain Danu replied in his calm, hyper-vigilant baritone. He flashed a hand signal for the entire group to halt and lock down into a defensive posture. "Everybody, raise your weapons. Keep your flashlights dialed down so we don't silhouette our position."

Zulfa dropped to one knee beside one of the footprints. He noticed a strange residual substance smeared around the claw impressions—shards of a glowing blue liquid metal that pulsed sluggishly, much like a living organism's heartbeat.

"Hang on... this is fascinating," Zulfa muttered, drawing his utility knife from his cargo pants pocket to carefully harvest a tiny fleck of the glowing metal.

"Zulfa, what are you doing? Don't touch that blindly!" Naya warned anxiously, shuffling closer to him.

"I just want to analyze it, Naya," Zulfa answered. He lifted the knife tip bearing the blue metal shard, bringing it closer to his flashlight beam.

The moment the metal shard caught the light, it reacted instantly. The metal flickered rapidly, emitting a micro-thermal wave that made the knife in Zulfa’s hand vibrate violently.

"This isn't ordinary metal or raw mined ore," Zulfa analyzed, awe warring with wariness in his tone. "Its molecular structure blends solid mechanical engineering with living biological energy... it looks uncannily like the Aether-Tech I saw in my father's notes, but on a far more primordial and raw scale."

"You mean this metal is alive?" Naya asked, her eyes blowing wide as she stared at the pulsing blue fleck on the knife blade.

"Not just alive," Captain Danu cut in sharply, his eyes locked on the pitch-black tunnel mouth stretching before them. "That metal is part of a scanning system or a tracking beacon. And if these footprints are fresh... that means something or someone crossed this exact path shortly before we arrived."

The atmosphere inside the colonial tunnel warped into something suffocatingly lethal. The air grew steadily colder, carrying a faint whiff of sulfur riding an underground draft. Psychological tension spiked in the chest of every group member, realizing that within the dark embrace of this mapless maze, they were far from alone.

"Captain... I think I heard something," whispered one of the resistance fighters in the center rank, his voice trembling heavily. "The sound of scraping metal... like claws dragging against stone."

"Quiet, everyone," Danu ordered firmly.

They fell dead silent, holding their breath, straining to listen across the eternal stillness of the earth's belly.

Click... scritch... click...

The scraping noise was real. It echoed faintly from around the tunnel bend ahead, falling into a rhythmic cadence that grew steadily louder, closing in on Zulfa's group.

Zulfa rose slowly, sliding his knife away as he gripped the borrowed resistance assault rifle tight. He stared down the dark bend ahead, his heart hammering against his ribs.

Suddenly, at the far end of the pitch-black corridor, a pair of sharp, glowing yellow light points ignited within the darkness, hovering roughly two and a half meters above the floor.

Those light points weren't alone. The next second, dozens more yellow light points flickered into existence in a row along the tunnel walls and ceiling, forming a flawless, enveloping trap.

"They're above us... and in front!" Naya gasped in panic, clutching Zulfa's jacket sleeve.

From out of the dark tunnel, a towering humanoid silhouette with a hunched, massive posture stepped forward into the flashlight beam. The creature possessed a skeletal frame woven from dark organic metal, with pulsating fiber-optic cable muscles glowing with a bright blue radiance. Its face lacked biological eyes, bearing instead a circular sensor plate glowing yellow, spinning sharply to lock onto Zulfa's group.

Behind the first creature, dozens of identical shadows peeled out of the gloom—clinging to the walls and ceiling with eerie, fluid, and utterly silent grace.

They were totally boxed in. Without a sound, the underground ancient wardens leveled their mechanical hand-blades, ready to slaughter anyone daring to trespass upon their sacred territory.