My lungs felt like they were filled with hot glass. Every breath scraped against my ribs, a jagged reminder that the eighteenth floor’s martial arts lesson was a distant memory. The air on the nineteenth floor had weight. Sulfurous and dense, it pressed down on my collarbones until they ached.

I stared up at Mount Agony. The trail spiraled upward, a crumbling scar carved into a peak that seemed to pierce the Tower’s ceiling. At my feet sat the source of my suffering.

The Boulder of Sin.

Five meters of perfectly spherical obsidian. When I placed my hand against its surface, the weight went beyond physical. Something spiritual lived in that stone, like the collective regrets of a thousand dead men pressing against my palm.

『Floor 19: The Myth of the Sisyphus Protocol』

『Main Scenario: Push the Celestial Boulder』

『Objective: Push the Boulder of Sin to the peak of Mount Agony.』

『The Rules: Failure to maintain upward momentum will cause the boulder to reset.』

『Lives Remaining: ‪♡‪♡‪♡』

Three red hearts pulsed above my head, flickering in the dim purple twilight. Other climbers struggled around the mountain’s base. New faces, players who had apparently rushed through the lower floors while I rewrote fables.

"Move it, you bastard! Move!"

Ryu Ji-won screamed at his boulder. The man was built like a bear, a berserker type with arms thick as tree trunks. His "Iron Blood" aura turned his skin a dull metallic red. Beside him stood Park Sang-ho, a support mage whose "Golden Bell" barrier shimmered against the first wave of monsters.

"Ji-won, wait! The forums said we should wait for the gravity cycle to shift!" Sang-ho’s face was pale with effort.

"The forums are useless!" Ji-won roared, his boots cracking the diamond-hard stone. "This isn’t ’Hard Mode’ anymore. This is Hell! The gravity shifts every ten seconds!"

He was right. The Sisyphus Protocol. In the Old World, this floor buried every "Pure Strength" build. People thought they could muscle through it. They forgot that Sisyphus was a king broken by his own hubris, and the Tower loved breaking kings.

I gripped the obsidian surface, digging my heels in.

The boulder didn’t budge. My [Singularity] skill sat at Level 5: [Event Horizon]. I felt space around me warping, trying to compensate for the crushing pressure, but the mountain itself was an anti-magic zone for anything outside gravity-based skills.

"Fine," I muttered through gritted teeth. "You want a struggle."

I activated [Singularity] - Level 2: [Gravitational Pressure]. Instead of pushing, I tried to lighten the stone’s gravity. For a split second, it felt weightless. I pushed.

A chorus of shrill shrieks erupted from the clouds. Harpies. Their feathers were jagged shards of flint that hummed with kinetic energy. They dove at the boulder, talons extended.

"They’re trying to tip it!" Sang-ho screamed. He cast a tether of golden light to anchor the rock, but a Gravity-Golem materialized above him. A massive floating pile of sentient boulders.

The Golem didn’t attack. It just existed. Local gravity increased in a ten-meter radius.

CRACK.

Park Sang-ho’s knees buckled. His Golden Bell shattered. The boulder he and Ji-won were pushing suddenly accelerated backward.

"NO! GET OUT OF THE WAY!"

Too late. The hundred-ton sphere rolled over Sang-ho like a dried leaf. A sickening crunch. His first heart vanished. He respawned ten meters back at the trail’s start, gasping, eyes wide with trauma.

I didn’t have time for pity. My own boulder was sliding.

"Exchange," I whispered.

I swapped positions with a pebble five meters up the trail. I appeared above the boulder, using the swap’s momentum to hammer my shoulder into obsidian. The slide stopped. The weight crushed down on me.

My mana veins bulged beneath my skin. In the Old World, I’d cleared this floor with a hundred summons acting as a human chain. Here? Hell Mode meant the boulder’s weight scaled with the number of helpers. A test of individual soul-weight.

Step. Step. Step.

Every meter felt like a kilometer. Harpies clawed my back, flint-talons drawing bloody furrows through my shirt. I didn’t defend myself. Taking my hands off the boulder for even a second would trigger the Sisyphus Protocol. Back to zero.

I looked down. At the mountain’s base, standing in a lake of shadow, was the Floor Warden. A Titan. Sixty meters tall, skin made of the same obsidian as the boulder. The "Unkillable Boss." Forum posts said to avoid it at all costs. The only way to clear was reaching the summit.

Fools, I thought, blood dripping from my nose. Sisyphus never won by reaching the top. He won by accepting the descent.

But accepting the descent required a catalyst.

"Ji-won! Sang-ho!" My voice sounded like gravel in a blender. "Stop trying to hold the summit! Push it to the 90th percentile and wait for my signal!"

"Are you crazy?!" Ji-won yelled, his metallic skin cracking under three Gravity-Golems. "If we let go near the top, it’ll reset the whole floor!"

"Just do it! If you want out of this loop, you have to break the fable!"

I pushed harder. I channeled [Singularity] - Level 3: [Compression]. I compressed the space behind my feet to create a solid anchor. The ground beneath me turned into super-dense matter, preventing the crumbling trail from giving way.

Hours passed. Maybe days. Time was as heavy as gravity on Mount Agony. I died once. A harpy dive-bombed my head while a Golem increased the weight of my eyelids. I lost focus for a heartbeat. The boulder slipped. I was pulverized.

Being crushed is something you never get used to. The sudden stop of your heart. The sound of ribs becoming shrapnel. I respawned, one heart missing, my soul frayed.

[‪ ‪♡‪♡]

"Again," I hissed.

I pushed. Died. A Golem appeared directly above me, increasing gravity tenfold. My spine compressed. My legs shattered. The boulder rolled back.

‪[♡]

I respawned. Pushed. Made it to the 40% mark. A harpy’s talon pierced my eye. I lost balance. The boulder rolled.

I respawned at the base. No hearts above my head this time. Just a countdown.

『Lives Remaining: 0』

『Retry Available: 10 minutes』

I sat there, chest heaving, watching Ji-won and Sang-ho struggle at the 60% mark. They were on their last hearts. They looked like ghosts.

The ten minutes passed. Three hearts appeared above my head again.

I started over.

Died at the 30% mark. A flock of harpies swarmed me. I tried to fight them off. The boulder rolled.

Respawned. Died at the 50% mark. Golem ambush.

Respawned. Made it to 70%. Ji-won called out to me, asking for help. I diverted my path. Tried to assist. My boulder rolled back while I was distracted. Died when it crushed me from behind.

Respawned.

I stared at the boulder. Then at Ji-won and Sang-ho struggling in the distance.

When did I start caring?

The thought came unbidden. In the Old World, I climbed alone. I watched guilds tear themselves apart. Watched teammates sacrifice each other for a single extra life. I learned early that the only person you could rely on was yourself.

So when did I start trying to save them?

I pushed the boulder. Made it to 45%. Ji-won screamed for help. His boulder was sliding.

I kept pushing.

"Singularity! Help!" Sang-ho’s voice was desperate.

I kept pushing.

Their boulders rolled back. They died. Respawned at the base.

I made it to 62%.

Died to a harpy swarm.

Respawned. Pushed. 73%. Ji-won and Sang-ho were at 55% this time. They were coordinating better.

"We need to work together!" Ji-won shouted at me.

I ignored him. Pushed to 81%.

A Golem appeared. I used [Exchange] to swap positions with a rock fragment behind it. Appeared at its back. Kept pushing while it looked for me.

85%.

The Floor Warden began moving. Its thunderous steps shook the mountain. Each footfall disintegrated parts of the trail.

Ji-won and Sang-ho were at 70% now. They were shouting something about teamwork. About combining our strength.

I was at 89%.

A harpy squadron dove at me. I compressed the space around my body, creating a gravitational shield. They splattered against it like bugs on a windshield.

91%.

The Titan Warden was climbing faster now. Its shadow fell over the trail. Ji-won and Sang-ho were at 75%.

"Singularity! Wait for us! We can beat this together!" Sang-ho’s voice carried up the mountain.

Together.

I laughed. The sound was harsh, broken. When had "together" ever worked in the Tower? The Tower was a machine designed to grind cooperation into dust. It rewarded the selfish. The ruthless. The ones willing to step over corpses to reach the next floor.

92%.

I’d died seventeen times trying to account for them. Seventeen times trying to be something I wasn’t.

A protector. A leader. A good person.

The Titan’s hand reached toward me. Its gravity aura was crushing. The boulder started to crack under the pressure.

I looked at the summit portal twenty meters away. The trap portal, shimmering like salvation.

Then I looked at the Titan’s obsidian chest.

Something inside me snapped. Maybe it was the eighteenth death. Maybe it was the realization that I’d been playing a role that didn’t fit. Maybe it was just the Tower finally breaking through the thin veneer of humanity I’d been wearing.

I started laughing.

Really laughing.

The sound echoed across Mount Agony, wild and unrestrained.