The door to Floor 4 slid open with a short, indifferent hiss—more like a mechanical shrug than an announcement.

  Z-69 stepped through.

  He didn’t find a battlefield, or a simulation chamber, or a pressure hellscape.

  He found a box.

  The “waiting room” was barely larger than a freight container.

  Metal walls.

  Low ceiling.

  Air that felt slightly compressed, like someone had tried to fold an atmosphere into a space too small to hold it.

  No furniture, no console, no obvious camera.

  Just emptiness.

  In front of him, a hologram flickered to life, suspended in midair. Its lines of text rolled past in a sterile white font:

  “Floor 4 will activate when the team has three contestants.”

  Z-69 stared at the word for a heartbeat.

  Team.

  Elise had said as much before The Tower began, but he’d never trusted anything until he saw it with his own eyes.

  He didn’t like teams.

  He didn’t like variables he couldn’t control.

  He especially didn’t like the idea of being locked in a survival scenario with two humans while something inside his chest was starving for energy and occasionally tried to eat anything that moved.

  Still, the rule was the rule.

  If Floor 4 demanded three bodies, then Floor 4 would get three bodies.

  He exhaled slowly, more out of habit than need, and did what he could in the sliver of downtime he’d been given.

  He checked his gear.

  Heaven-Sundering Blade. The familiar weight of it settled against his palm like an extension of his arm.

  Sidearm: an old, scratched energy pistol John had been forced to give him. Its power cell was half spent. That was still half more than nothing.

  Six packets of high-energy dried meat—each one a compact block of calories and chemicals, the taste of battery-coated jerky.

  And one slender vial of suppressant.

  He held the vial up to the light, watching the liquid inside shift with slow, viscous reluctance.

  All that stood between him and The Hunger, if things went wrong again.

  John’s voice echoed in his memory, dry and irritated:

  “This is all I have left. Don’t waste it. If you go feral, I’m not cleaning up the mess.”

  Z-69 tucked the vial away.

  He didn’t answer ghosts.

  The door behind him hissed again.

  Z-69 turned, half expecting another machine.

  What the Tower delivered instead was a stretcher—and a corpse-shaped bundle.

  Two medical drones hovered in, their movements smooth and utterly uncaring.

  They carried a stretcher between them like a piece of cargo.

  The human on it was wrapped in bandages from shoulder to ankle, more cloth than skin.

  Ten.

  The drones dumped him onto the floor without a word and flew back out, the door sliding shut behind them as if erasing a completed delivery.

  Ten groaned.

  It sounded like someone trying to cough underwater.

  He tried to push himself upright.

  His arms shook violently under his own weight.

  His legs didn’t even pretend to help.

  Z-69 watched for a moment, then stepped forward and pulled him up by the collar with one hand.

  Ten swayed on his feet.

  His face was gray with exhaustion, eyes red-rimmed, lips cracked.

  He looked less like a contestant and more like a malfunctioning scarecrow someone had dressed in human skin.

  Z-69’s gaze ran up and down him, flat, clinical.

  “You’re still alive?”

  Ten forced his mouth into something that wanted to be a smile.

  “I… think so.”

  “How?” Z-69 asked.

  Not mocking.

  Just honestly baffled.

  Floor 1: Sensorium.

  Floor 2: Balance.

  Floor 3: Pressure.

  He himself had nearly been smashed into paste before The Hunger tore its way out.

  Ten, meanwhile, looked like a strong wind could break his spine—yet he was here.

  Ten scratched the back of his head weakly.

  “I… I don’t really know. I just did what my body told me to do and somehow… I didn’t die.”

  Z-69 recalled the story Ten had given earlier—about winning a fight because his opponent had slipped and knocked themselves out.

  The kind of nonsense no battle planner would ever factor in.

  “You might be the unluckiest lucky brat I’ve ever seen since I woke up.” Z-69 said.

  He didn’t sound impressed.

  He sounded like someone describing a glitch.

  Ten glanced at the hologram.

  “We… we’re in already? This is… Floor 4, right?”

  “Yes. The entrance.” Z-69 replied. “We still have six floors left.”

  Ten’s smile twisted, part grimace, part resignation.

  Fear flickered behind his eyes, but it had a strange edge to it now—cauterized by repetition.

  When terror becomes routine, it calcifies into something else.

  Resolve.

  Or numbness.

  Sometimes both.

  The door opened again.

  Footsteps.

  Confident.

  Light on the heel, heavy on the ball of the foot.

  A runner’s stride.

  Jin stepped in.

  He didn’t look much better than Ten—just more stubborn about it.

  His combat suit had been shredded along the arms and sides, scorched in several places.

  One shoulder was stained with a dried smear of brownish red.

  His hair clung to his forehead with sweat.

  There were small cuts on his cheekbones and jaw.

  He was still standing like he owned the room.

  His eyes locked onto Z-69.

  “We meet again, silverhead.” he said, voice hoarse but edged with familiar arrogance. “This time, I won’t lose to you.”

  He slid one foot back, weight lowering instinctively, shoulders angling.

  Even exhausted, his body fell toward a fighting stance like it was his default state.

  Z-69 didn’t move.

  “You’re still impulsive.” he said. “Unfortunately for you, our rematch will have to wait.”

  Jin’s eyes narrowed. “Yeah? You scared I’ll be the one kicking your ass this time?”

  Z-69 tilted his chin toward the hologram.

  “Read.”

  Jin’s gaze flicked to it.

  Team of three.

  Survival.

  Exit.

  His jaw tightened.

  Slowly, reluctantly, he eased out of his stance.

  “This isn’t over, silverhead.” he muttered.

  Z-69’s mouth curved into the ghost of a smirk.

  “I’m always ready.”

  Unlawfully taken from Royal Road, this story should be reported if seen on Amazon.

  Ten darted between them like a terrified referee who had no business being in any ring.

  “H-hey, we’re on the same side now, remember? Team. Floor 4. Not the time to punch each other, right?”

  They both ignored him.

  The ceiling lights flickered.

  The system voice descended like a hammer:

  “Floor 4: SURVIVAL.”

  “Assessment: Survival skills – teamwork – group coordination.”

  “Environment: Artificial Forest – 120 square kilometers.”

  “Objective: Survive for 24 hours and locate the exit to Floor 5.”

  An artificial forest.

  Z-69’s eyes narrowed slightly.

  “A forest, underground.” he thought.

  Jin scoffed aloud. “A forest? Down here? They expect us to believe this place has trees?”

  Ten murmured, almost to himself: “If they call it a forest here… it’s probably the kind that eats people.”

  The door in front of them opened.

  Blackness yawned beyond.

  No, not blackness—absence.

  The three of them stepped forward.

  The world shifted.

  The smell hit first.

  Wet earth.

  Cold metal.

  The sharp, metallic tang of something like ozone, mixed with the faint acrid bite of chemical residue.

  Z-69 looked up.

  Above them was a sky—or at least, something that wanted to be one.

  An ashen expanse stretched overhead, clouds rendered from dense energy particles.

  They pulsed faintly, glitching along their edges when they moved.

  No stars.

  No sun.

  Just a pale gray glow diffused across the entire dome.

  Around them, the forest spread out in every direction.

  Trees.

  Dozens. Hundreds. Thousands.

  Trunks as thick as support pillars, bark a dull matte gray.

  Branches spreading out like skeletal arms.

  Leaves a strange, metallic blue, edges so sharp they could cut skin.

  Everything in this place looked like someone had tried to reconstruct a forest from memory using industrial scrap.

  Ten turned in a slow circle, awestruck and horrified.

  “This is… this is actually kind of beautiful.” he said softly.

  Jin walked up to the nearest trunk and kicked it.

  The impact rang down the length of the tree like a bell.

  “Yeah, breathtaking.” Jin muttered. “If you’re into iron lungs and knife leaves.”

  Z-69 rested his palm against the bark.

  It was cold at first.

  Then, under his touch, it warmed faintly.

  He pressed a little harder.

  Something underneath the bark twitched.

  He pulled his hand away.

  The spot where he’d touched warped—metal shifting like muscle.

  A moment later, a ring of pale blue moss unfurled from the trunk, reaching out toward where his hand had been, like a cautious animal trying to grab hold.

  Ten flinched.

  “D-don’t let it touch you!”

  Z-69 had already stepped back.

  “This place is alive.” he said.

  Jin snorted. “Alive and unfriendly. Great.”

  They advanced cautiously.

  The deeper they went, the more the forest changed.

  Light faded fast.

  The ashen glow of the artificial sky dulled, swallowed by overlapping canopies of metallic leaves.

  Shadows braided together between the trunks like dark ropes.

  The soundscape was wrong.

  No insects.

  No birdsong.

  No rustle of small creatures moving through foliage.

  Only a distant, low vibration, like the entire forest shared a single heartbeat.

  After a while, Jin’s impatience boiled over.

  “If this is a survival test, sooner or later we’re going to need food and water.” he said. “And I don’t see any vending machines.”

  Ten sniffed the air tentatively.

  “There’s… something.” he said.

  Z-69 smelled it too.

  Moisture. Cool. Chemically sharp.

  “Left.” Z-69 said.

  They moved through the trunks until the trees parted enough to reveal a stream.

  At least, it looked like one.

  Clear liquid flowed along a shallow channel, winding through the forest floor with delicate curves.

  The surface glimmered with reflections of the metal leaves overhead.

  It could have been a postcard.

  A quiet forest brook.

  Jin crouched beside it, dipping his fingers toward the surface.

  “Wait!” Ten shouted.

  His voice cracked from urgency and raw fear.

  Too late.

  Jin’s fingertips brushed the liquid.

  For a brief second—nothing.

  Then the pain hit.

  His skin went red, blistering almost instantly.

  “SHIT—!” He jerked back, clutching his hand. “That burns!”

  The liquid began to hiss where it clung to his skin, eating at the flesh beneath.

  Z-69 seized his wrist and scraped the fluid off with the flat of his blade, fast enough that it only took the top layer of skin with it.

  Jin hissed between his teeth.

  “Acid.” Z-69 said calmly.

  Jin stared at the stream as if it had personally insulted him.

  “Who the hell installs an acid river in a forest sim?”

  “Someone very committed to thematic consistency.” Z-69 replied. “Everything here exists to kill us.”

  Ten swallowed.

  “Then… what do we drink?”

  Z-69 closed his eyes.

  The Hunger stirred faintly, like a half-sleeping animal rolling over.

  Energy. There…

  He followed the sensation, stepping away from the stream.

  Near the bank stood a large tree, thicker than the rest.

  Its bark seemed darker, veins of faint green glowing beneath the surface like deeply buried circuitry.

  Z-69 placed his hand against it and, with a quick motion, cut a shallow line.

  Instead of sap, a pale green fluid seeped out.

  It was warm, faintly luminous, and viscous, clinging to his palm like living gel.

  He raised his hand to his mouth.

  Ten nearly choked.

  “W-wait, you’re not going to—”

  Z-69 tasted it.

  His eyes flickered once.

  Bitterness. Metal. A faint chemical aftertaste.

  It hit his system like a warm static—energy, crude but usable.

  “Better than acid.” he said simply.

  Jin made a face. “You can’t just drink glowing tree juice and call it a day.”

  Ten’s stomach growled audibly.

  He looked at the sap, then at the acid stream, then at Z-69.

  Between slow, certain death and fast, disgusting survival—

  He chose survival.

  He cupped his hands, caught a bit of the fluid, and gagged it down.

  It burned his throat, but not the way acid did.

  It was more like swallowing concentrated energy, the kind that made his heartbeat speed up and his fingertips tingle.

  Jin held out longer than either of them.

  But in the end, hunger won.

  “Tch.” he spat, grabbing a bit of sap and forcing it down. “If I mutate into a tree, I’m blaming you.”

  They pressed onward.

  The deeper regions of the forest grew colder.

  The ground hardened beneath their boots, then softened again, as if the terrain was adjusting itself—testing their steps.

  The metal leaves overhead whispered without wind.

  Ten’s eyes kept flicking to the ground.

  He stopped suddenly.

  “Something…” he murmured. “Under us.”

  Z-69 looked at him.

  “Explain.”

  Ten pressed both palms to the soil, closing his eyes.

  “There are… small things. Fast. They’re moving in groups. Six… no, eight. No, nine—no, one just left the pattern…” His brows knitted. “They don’t move like animals. More like… blades.”

  “Good.” Z-69 said. “Keep tracking them.”

  “Uh, I–I wasn’t trying to—”

  The forest floor bulged.

  Then cracked.

  Metal shards burst upward in scattered arcs, followed by the bodies attached to them.

  They weren’t animals.

  They were machines.

  Beetle-sized constructs with segmented shells and legs like knife edges—Swarm Scarabs—each movement too smooth, too precise to be natural.

  Their bodies were low and compact, built to hug the ground.

  They didn’t see.

  They didn’t smell.

  They felt*.*

  Vibration-based hunting systems.

  Underground skirmish units.

  They surged toward the trio in a wave.

  Jin vanished.

  One moment he was standing behind Z-69, the next he was a smear of motion, reappearing three meters away with a Scarab’s severed body twitching under his heel.

  “Tch. Bugs now?”

  One Scarab’s blade narrowly missed his ankle.

  “They move along ground vibrations!” Ten yelled. “If you run in straight lines, they’ll predict the path!”

  “I KNOW THAT!” Jin snapped back.

  Z-69 stomped the earth.

  A nearby tree tipped, then fell, its massive trunk crashing down in front of the advancing swarm.

  For 0.3 seconds, their predictive systems scrambled.

  That was enough.

  Z-69 stepped in.

  Heaven-Sundering Blade carved through the first Scarab, the second, the third. Precision arcs. No wasted motion.

  Jin used the falling trunk as a ramp, sprinting up its side and launching off, driving a heel into the exposed underside of another Scarab, crushing its core.

  Ten stayed back, breathless, calling out patterns:

  “Left side—five incoming! Two circling behind! Watch your back—no, no, they’re redirecting, ground shifted—”

  Z-69 responded to the calls, his body adjusting mid-swing.

  Jin’s footwork flowed around his range, turning openings into execution points.

  Thirty seconds later, the ground was littered with shattered shells and smoking cores.

  Jin landed lightly, brushing dust off his clothes.

  “That.” he said between breaths, “was clean.”

  Ten blinked, stunned.

  “I… I just said what I felt. You two did all the work.”

  Z-69 picked up a broken Scarab, weighed it in his hand, then let it drop.

  “Not bad.” he said. “But this is only bait.”

  Jin’s expression soured.

  “You always know just what to say to ruin a moment.”

  The forest trembled.

  This time it wasn’t localized.

  The vibration moved through the ground in a long, rolling wave, like something massive had stirred beneath their feet.

  Metal leaves shook.

  The artificial sky dimmed a fraction.

  Ten’s eyes widened.

  “That… that’s big.” he whispered. “Really big. And deep. I can’t even… feel all of it at once.”

  “How big?” Jin asked.

  “Sixteen meters, approximately.” Z-69 answered.

  Jin stared at him.

  “Next time.” Jin said slowly, “start with that.”

  The ground exploded.

  Dirt, stone, and splintered roots shot upward as something vast and metallic tore its way out from below.

  A worm.

  A gigantic, segmented monster of steel and rotating parts, its body like a chain of armored rings fused together.

  Its head was a circular maw lined with concentric rows of metal teeth, each ring spinning in the opposite direction of the one beside it.

  When it inhaled, the air howled.

  The suction ripped smaller rocks from the ground and dragged them into the maw, where they vanished in sprays of sparks.

  Jin dug his feet into the soil.

  “THAT’S NOT A WORM, THAT’S A WHOLE TRAIN!”

  “Run!” Ten shouted.

  They tried.

  But the pressure dragging them backward was too strong.

  Even Jin, with his speed, found his movement skewed—each step resisted by invisible hands tugging at his limbs.

  Z-69 slammed his blade into the ground.

  The steel bit deep, anchoring him.

  He grabbed Ten by the collar with his free hand.

  Jin’s body was already sliding.

  He twisted mid-drag, kicking both feet into the trunk of a nearby tree, hooking himself there like a human anchor.

  The worm roared again, maw opening wider.

  Z-69’s eyes thinned.

  Then he yanked his blade out of the ground.

  “Cover him.” he said.

  “For what?!” Jin snapped. “You’re not seriously—”

  Z-69 ran straight toward the monster.

  The suction increased.

  It tried to pull him off his feet.

  He let it—using the force to carry him forward faster.

  He hit the border of its maw, metal teeth whirling toward him like a storm of saw blades.

  He caught two of the rotating rings with his bare hands.

  The friction seared dead flesh from his palms.

  He pulled.

  Metal screamed.

  Teeth bent and warped, buckling under the unnatural force driven through his arms.

  The worm thrashed, its body slamming against trees, shaking the entire forest.

  Jin blurred out of his anchoring position, appearing beside the worm’s head, delivering a full-speed kick to one of the sensor clusters embedded in its side.

  Metal cracked.

  The beast spasmed.

  Ten, trembling, pressed his hands to the ground.

  “The third segment!” he shouted, voice raw. “Its vibration is different there—that’s the core connector!”

  Z-69 ripped himself free from the shattered maw and moved.

  He jumped, using the worm’s own convulsions as momentum, driving himself upward and then down.

  The Heaven-Sundering Blade plunged into the third segment.

  For a moment, nothing happened.

  Then the entire worm convulsed.

  A surge of discharge burst from the wound, spraying sparks and shredded alloy.

  Its scream was a vibration, not a sound—so deep the forest floor rippled.

  Then it collapsed.

  Sixteen meters of metallic carcass crashed down, tearing grooves into the soil, toppling trees, throwing all three of them off balance.

  Silence followed, deafening after the noise.

  Jin lay on his back, chest heaving.

  “What the hell.” he panted, “is Floor 4 supposed to be?”

  Ten hung onto a half-broken trunk, legs shaking.

  Z-69 cleaned his blade with a small flick.

  “Survival.” he said.

  No one argued.

  Time passed.

  How long, none of them were sure.

  The artificial sky brightened and dimmed in an imperfect arc, as if the system had been forced to approximate “afternoon” from old data.

  They walked.

  They found no real food.

  They found no clean water.

  They found more strange lifeforms—some they avoided, some they killed, some they stared at warily and moved on.

  Ten’s stomach growled again.

  “I’m… hungry.” he whispered.

  Jin frowned. “You ate more of that tree puke than either of us.”

  “My body burns through it fast.” Ten said. “Maybe because I’m always on edge…”

  Z-69 stopped.

  He knelt by a tree root and began digging into the wet soil.

  Ten watched, confused.

  “What are you doing?”

  Z-69 didn’t answer.

  His fingers sifted through mud until they found something… moving.

  He pulled it out.

  A cluster of small, translucent organisms writhed in his palm—tadpole-like shapes glowing faintly, their bodies pulsing with a dim, radioactive green.

  Jin recoiled.

  “If you say ‘edible,’ I will shoot something.”

  Z-69 crushed the mud away, leaving only the creatures.

  He put one in his mouth.

  Ten made a sound somewhere between a squeak and a gag.

  Z-69 chewed.

  Swallowed.

  “They’re edible.” he said.

  “ON WHAT PLANET?!” Jin snapped.

  “Not this one. But we’re not on a planet.” Z-69 replied. “We’re in a machine that simulates death.”

  He handed one of the glowing creatures to Ten.

  The boy stared at it, eyes wide and wet.

  “If you don’t eat.” Z-69 said calmly, “You will die faster.”

  Ten shut his eyes and tossed it into his mouth.

  The texture was disgusting—slimy and crunchy at the same time, like someone had combined jelly with glass shards.

  It tasted of metal, salt, and electricity.

  His whole body shuddered.

  But a wave of warmth followed, spreading from his stomach outward.

  Jin glared at the remaining cluster.

  Muttered something obscene.

  Then picked one up and swallowed it.

  “If I grow extra arms, I’m sending the bill to whoever runs this floor.” he grumbled.

  They walked until the artificial sky finally dimmed for real.

  Light drained out of the forest.

  The metallic leaves turned from blue to a dark, blood-tinted red as ambient LEDs hidden in their veins activated.

  The forest looked less like a simulated ecosystem now—

  And more like a killing field.

  The wind returned.

  Thin. Cold. Carrying with it a new set of sounds.

  Soft clinks of metal on metal.

  Distant dragging noises.

  Something like a whisper transmitted through rusted wire.

  Z-69 slowed.

  “Stop.” he said quietly.

  Ten and Jin halted instantly.

  He looked around.

  The forest they’d traversed under that pale gray sky had been dangerous.

  But what he felt now wasn’t danger.

  It was intention.

  As if the entire floor had been waiting for night.

  Behind them, somewhere far in the trees, something laughed.

  A small, mechanical chuckle. Almost playful.

  Ten shivered.

  “Night just started, right?” Jin said.

  “Yes.” Z-69 replied.

  The Hunger stirred again, just beneath his heart.

  “Good.”

  “Night is when things taste best.”

  It whispered.

  Z-69 ignored it.

  He took one more step forward, into the deepening dark.

  “From here on.” he said softly, “it’s real survival.”

  The forest exhaled.

  And Floor 4 truly began.