The pneumatic lock slammed shut with a resounding bang, echoing through the corridor, sealing their escape route completely. The reinforced steel door behind them became a wall of despair.
Ahead lay the B1 hallway, dark and freezing like a morgue freezer. Red emergency lights pulsed like a heartbeat, illuminating six pairs of blood-red eyes staring back. Six mutated police K9s stood rigid, panting harshly, acidic saliva dripping viscous and corroding the concrete floor with sizzling pits. They didn't charge mindlessly to tear apart their prey like human zombies. The virus had preserved their pack-hunting instincts and amplified their ferocity to a new level.
The alpha in the center crouched low, muscles rippling beneath gray bone-armored skin. It bared serrated shark-like teeth.
Thump... Thump... The massive heartbeat from the lowest level echoed like a war drum, signaling the hunt's start.
The alpha lunged. It propelled itself from the concrete with blinding speed, jaws gaping to snap Shi-hun's throat in one bite.
Shi-hun didn't dodge. He drew the Glock 19 from his jeans waistband with muscle-memory speed, raised it to eye level, and squeezed the trigger without hesitation.
Bang!
The gunshot roared in the sealed corridor, deafening and ringing in their ears. Muzzle flash flared, piercing the darkness for a split second. The 9mm bullet streaked through the air, striking the bone armor on the alpha's forehead.
Crack! Metal flattened and ricocheted with sparks. It didn't penetrate.
The beast staggered mid-air from the impact but rolled to the ground, regaining footing unscathed.
Handgun rounds couldn't pierce their skull armor. Shi-hun assessed coldly. He needed weak points—eyes or the open maw. But six lightning-fast mutants in flickering red light were a tactical nightmare. Blind firing in the dark wasted ammo, and missing meant both of them becoming shredded meat.
They fanned out intelligently, using the emergency lights' flickering outages to blend into shadows. They were encircling, closing every escape vector.
"Watch your back," Shi-hun ordered, ears still ringing from the shot.
Yu-jin spun, back against the sealed door, raising her metal pipe defensively. Her hands trembled. The acrid gunpowder smell mingled with blood and frost in the air.
One K9 burst from the right shadows, targeting Yu-jin. She swung the pipe with all her strength. Metal struck its rib cage with a dull thud, but it didn't stop. It clamped jaws on the pipe, serrated teeth grinding through metal with an ear-piercing screech. The massive yank nearly tore it from her grip. Pain lanced through her cracked ribs, forcing her to her knees with a agonized groan.
Shi-hun swung his barrel toward it, but another K9 charged from his left blind spot. It tackled his side full-force like a runaway freight train. The air was violently expelled from his lungs. Having no superhuman durability to absorb the blow, the impact hurled him against an iced pipe on the wall, bruising his ribs instantly.
The Glock veered off-target. Razor claws raked his left shoulder, shredding his gray hoodie and slicing flesh, blood spraying.
He kicked its chest to create distance, breathing heavily. Fourteen rounds left in the magazine. Six mutants remaining. They were too fast.
He needed stationary targets.
Shi-hun gritted his teeth. As the red light flared, he yanked a fistful of his own hair out in one pull. The metallic taste of blood from biting his lip sharpened his focus.
[Initiate Cloning Process? Cost: 5 days. Yes/No]
He confirmed. [Remaining Lifespan: 191 days]
***
The clone materialized mid-encirclement in a flash. Blue particles wove flesh rapidly, forming another Shi-hun in the corridor's center—unarmed, unprotected, a fresh slab of meat inviting slaughter.
Draw them in, Shi-hun commanded mentally.
The clone didn't hesitate. It bellowed a guttural yell and charged the K9 wrestling Yu-jin's pipe, bare hands grabbing its neck to wrench it away.
The pack's hunting instincts kicked in at the sight of defenseless prey rushing center stage. All six abandoned prior targets, growling and pouncing from every direction like piranhas.
"Shi-hun! What are you doing!" Yu-jin screamed, seeing the man (she thought was him) swarmed and torn.
Six wolf-dogs pinned the clone to the floor. Gaping jaws clamped on arms, legs, and neck. Serrated teeth ripped deep into soft tissue, tearing chunks free. Sounds of flesh shredding and bones snapping mingled with the beasts' roars. Fresh red blood splattered, staining the concrete.
And the real Shi-hun... leaning against the wall... felt it all.
A tsunami of hellish pain crashed into his nervous system. His eyes bulged, knees buckling to slam the concrete. He felt fangs embed in his jugular, calf muscles ripped apart, intestines clawed from his abdomen. Agony burned like acid dousing and ignition.
This was his chosen tactic: a sensory-linked meat shield.
Shi-hun bit his lip harder, fresh blood gushing to stifle screams. His brain told him he was being eaten alive, begging his body to writhe on the floor. But his iron will forced his muscles to obey. He raised the Glock 19, his hands violently shaking from the phantom torment, yet his black eyes remained dead and focused.
The wolf pack feasted ravenously on the clone... their frenzy made them static targets.
He drew a deep breath, forcing hands steady, aiming at the bloodied mass ahead.
Bang! A 9mm round pierced the alpha's eye socket as it mauled the clone's neck, blasting through brain and exploding the skull from inside. Black blood sprayed.
Neck pain lingered. The second tore the clone's left arm clean off. Shi-hun ground his teeth until his jaw ached.
Bang! Bullet pierced its gaping maw, severing the brain stem. It collapsed, twitching.
The third and fourth lifted blood-smeared muzzles from the clone's carcass, crimson eyes locking on the real Shi-hun. They realized. But a split second too late.
Bang! Bang! Precise double taps drilled their eye sockets. Both dropped limp atop the clone.
The fifth reacted, leaping aside and charging Shi-hun. No time to aim—he raised and fired mid-air.
Bang! Bang! Bang! Three rapid shots hammered its unarmored chest and underjaw. Mid-leap impact halted it, body crumpling at his feet with a final whimper before stilling.
The last, shredding the clone's leg, tried fleeing toward the stairs. Yu-jin lunged, smashing her pipe into its skull, staggering it. Shi-hun closed in, pressing the barrel to its temple.
Bang!
Deafening silence returned to the B1 corridor.
Blue system screens flashed rapidly in his mind.
[Clone Deactivated: Fatal Damage Sustained] [Transferring Harvest Results...]
[Kill Confirmed +1, +1, +1, +1, +1, +1. Total +6 days from Pack Elimination]
[Current Lifespan: 197 days]
The pain link severed. The mangled clone dissolved into red particles, fading into air, leaving only its blood pool and six mutant dog corpses strewn about.
Shi-hun slumped, palms on frigid concrete, gasping wildly for air. Nosebleed streamed freely. Blood from his bitten lip dripped. His body shook uncontrollably as adrenaline crashed, leaving bone-crushing fatigue.
Yu-jin lowered her pipe, legs buckling to sit against the wall. She stared at the man kneeling amid carnage. He'd used himself as bait... let those dogs devour him alive... for a shooting window.
What kind of human was he? This ruthless decisiveness, even toward himself—he viewed it as disposable "resource."
"You just... let them eat you," she said, voice quivering with horror.
Shi-hun rose slowly, wiping face and nose blood on his tattered hoodie sleeve. "It's mathematics," he replied, hoarse but icy, detached from prior agony. "Trade five days of lifespan for stationary targets that keep us alive. Worth the investment."
***
Before pressing on, Shi-hun returned to the alpha K9's corpse, noticeably larger than the others. Along its spine protruded a foot-long spike of black, unnaturally dense bone, like alloyed metal.
He knelt, drawing his duplicated kitchen knife, and began prying the spike from its back without qualm. Knife scraping bone echoed gruesomely. Yu-jin watched in disgust.
"What are you doing? We need to move," she urged.
"Looting," he replied curtly, yanking until the spike tore free with a wet rip. Black fluid dripped.
As his hand touched it, the system pinged differently.
[Detected Mutated Item: Calcified K9 Bone Spike]
Shi-hun's eyes glinted in the dark. His hypothesis confirmed. The system categorized it explicitly. Not mere corpse—this was an "item." The system wasn't just duplication and cloning; it held potential for crafting and evolution, if he gathered enough high-level monster parts.
He stowed the bone spike carefully in his backpack. Then he ejected the Glock's magazine—six rounds left. He needed full for deeper levels.
Touching it: [Duplicate? Target: 9mm Magazine (15 Rounds). Complexity: Medium-High. Cost: 5 days. Yes/No]
He agreed. Blue flash. A pristine, heavy 15-round mag appeared. He slapped it in with a click, racking the slide. [Remaining Lifespan: 192 days]
"Get up," he told Yu-jin. "We reach the source."
***
They passed the mutant dog carcasses, leaving the slaughterhouse behind. The B1 corridor ended at an open iron gate leading to a spiraling stairwell delving deeper. The freezing B1 chill oddly warmed as they descended to B2 and B3.
Not heater warmth, but humid, fetid heat—like a colossal creature's breath.
Thump... Thump...
The massive heartbeat grew clearer with each step, vibrating concrete until dust sifted from ceilings. It resonated in Yu-jin's chest, nauseating her. The atmosphere thickened, like wading deep water.
Finally, B3.
No zombies here. No signs of carnage. Only eerie silence punctuated by the chilling pulse. At the corridor's end: a massive circular steel door—the university vault. Titanium-alloy thick. Beside it, an electronic panel glowed green. Backup power oddly active.
Shi-hun approached the panel, recalling digits traded for bread that morning.
"Six digits, followed by command sequence..." he muttered, keying in.
Beep... Beep... Beep... Ping.
Green light flashed. Hydraulic hiss released pressure gas. Four massive bolts retracted with thunderous clanks. The vault door creaked open slowly, revealing dim interior gloom.
Shi-hun shoved it wider, shouldering the Glock and sweeping flashlight inside.
What lay within... wasn't mere arms or supplies cache as Professor Park assumed.
It was a vast underground bio-lab. Shattered test tubes, tangled wires, toppled medical gear. Center: a cylindrical safety glass tank, size of a water reservoir, webbed with cracks.
Inside: a massive crimson mass, vehicle-sized, pulsing in murky yellow fluid. Black veins thick as plumbing pipes linked it to ceiling conduits... feeding into the university's main ventilation.
Thump... Thump...
The mass was the heartbeat's source. Not a heart—but a "hive"... pumping viral spores into the building for weeks.
As Shi-hun's beam hit it, the mass twitched. A sickening, wet tearing sound echoed in the vault as a central fissure parted slowly, revealing dozens of gigantic, unblinking yellow eyes staring back.