Crimson Core

The sound of silence was eerie.

The gym, once a place of youth and laughter, now echoed with the strained breaths of survivors and the distant, haunting groans of the undead. Broken windows let in pale light. Shattered furniture and bloodied shoes littered the floor. It was no longer a school—it was a shelter carved from chaos.

Leo sat with his back against the gym wall, his black eyes fixed on the floor. His sword, stained with rot and blood, lay across his knees. He was silent—not just out of exhaustion, but calculation. The others thought they were safe. They weren't. This was only the beginning.

Damien Blake sat nearby, wrapping a cloth tightly around a gash on his arm. "Think this is happening everywhere?" he asked, not really expecting an answer.

"More than likely," muttered Miles, adjusting his cracked glasses. "This isn't some isolated outbreak. That explosion? It wasn't just noise. It felt… worldwide."

Evelyn stood near the entrance, sword drawn, eyes on the shadows beyond the door. She hadn't spoken much, but her presence was steady. Cold, but steady.

Riley Cross, brushing blood from her cheek, scoffed. "Yeah, no kidding. Zombies in homeroom? Pretty good sign of the end."

Leo didn't laugh. He didn't even smile. Instead, he looked at his hands—his fingers still faintly glowing from what he had done earlier. That core. That thing only he could see.

After killing that last zombie, something had been left behind—a pulsing, crimson core. No one else reacted to it. No one even saw it. It was as if it didn't exist to them. But for Leo, it had shined like a cursed gem in the dark. And when he touched it… when he absorbed it… something had changed.

> [Mutation Core Absorbed]

Hidden evolution path unlocked.

Stat bonus: +5 to Strength, +3 to Perception.

Warning: Mutation tier 1 active.

His body had surged with energy—and with something else. Something darker. He felt his senses expand slightly. Smells sharper. Hearing more attuned. He felt like something inside him had shifted.

And he wasn't going to tell a soul.

---

Earlier That Day

The fight had been brutal. One of the larger zombies—bloated, veiny, its face peeling with acidic drool—had charged into the gym just as the group tried to settle.

Leo had faced it head-on.

He dodged under its swing, rolled across the floor, and slashed at its knees. The sword barely cut through the thick, mutated muscle, but it was enough to stagger it. As it turned, Damien and Logan hurled chairs and debris to keep it off balance.

"Leo, its neck!" Ana shouted, having noticed a pulsing, swollen gland there.

Leo nodded and leapt forward, ducking a wild swing, and drove the blade into its neck. Black ichor burst forth. The monster shrieked and collapsed.

The others cheered.

But Leo didn't join them.

Because as the corpse cooled, the same faint red glow began to shimmer inside its chest. Like before. He knelt swiftly as the others looked away and slid his hand into the corpse.

His fingers met the core. It was hot. Alive. Pulsing like a heart.

He hesitated for just a moment—then closed his hand around it.

> [Core Absorbed]

Mutation Path: Tier 1 → Tier 2

+2 Strength, +1 Constitution

Warning: Side Effects Unknown.

His head spun.

And then it stopped.

Everything was… clearer. But colder too.

---

Back in the Gym

Victoria, Leo's older sister, stood near Evelyn, her gaze occasionally drifting to her brother. She had noticed something was off. He didn't speak. He didn't joke like the others. Something about the way he moved—more calculated, more distant—felt unfamiliar.

She stepped toward him. "Leo."

He looked up. "Hm?"

"You okay?"

He paused for a heartbeat. "Yeah. Just tired."

A lie. But convincing enough.

She nodded, though her eyes searched his for the brother she remembered.

Meanwhile, Ana was organizing a makeshift strategy circle. Using pieces of torn paper and debris, she outlined a basic perimeter. "We need shifts. Watch duty. Food scavenging. If we stay here, we need to make it work."

Logan raised his hand. "Uh, question—how long do we plan to stay here before we all go insane or starve?"

"Not long," Ana said, firm. "Just enough to rest. Then we look for supplies or somewhere better defended."

Riley crossed her arms. "Or we make this place better defended."

They bickered. They debated. They panicked quietly under layers of sarcasm and fake confidence.

Leo didn't speak. He was listening.

Every time someone died, the system had granted experience. That much was clear.

But only he… only he could consume the cores. And that made him something else entirely.

They were leveling up.

He was evolving.

---

Nightfall

That night, the group slept in shifts.

Leo didn't sleep.

He was outside, standing beside a broken vending machine, moonlight casting a faint glow on the bloodied concrete. He looked up at the stars. So beautiful. So distant.

Then he heard a growl.

A lone zombie staggered out from the bushes beyond the gym, jaw hanging loosely. It was different—its eyes were glowing slightly.

Mutated.

Leo smiled faintly. "Perfect."

The fight was short. Too short. He moved like a ghost. Sword flashed, the zombie screamed—and then it fell.

As expected, the core appeared.

He touched it.

> [Core Absorbed]

Mutation Tier 2 → Tier 3

+3 Agility, +2 Strength

Side Effect: Hallucination (Mild)

The world warped for just a moment. He saw red shapes on the walls—symbols, dancing like blood.

He blinked.

Gone.

He staggered slightly, catching himself. "Tch. Worth it."

But the voice in the back of his mind whispered louder now.

Consume. Grow. Evolve.

He didn't resist.

---

Morning

The group gathered near the gym entrance, having barricaded it through the night. Damien had stood watch, and now his eyes were baggy and red. "We need food. Water. I'm serious. There's nothing left here."

Miles nodded. "The science lab might have emergency rations. Or at least water purification stuff."

"I'll check it," Logan offered.

"No," Leo said, standing. "I will."

They turned.

Ana tilted her head. "You sure? You've been quiet since—"

"I'm sure."

He left before anyone could protest.

---

Science Lab

The lab was dark, but not empty.

Three zombies.

One of them looked… different. Its arms were bulkier. Its torso riddled with bone-like armor. A Level 2 variant.

Leo smiled.

The fight was bloodier this time. He lured them apart—broke a chair to stab one through the eye. Used a burner stand as a makeshift spear to impale another. The armored one took longer, even with Leo's enhanced strength, but he found its weak spot behind the spine.

When they fell, three cores shimmered on the ground.

He took all three.

> [Mutation Tier 3 → Tier 4]

+4 Strength, +2 Perception

Side Effect: Hunger Increase

New Skill Unlocked: "Predator's Pulse" – Temporarily sense lifeforms within 30 meters.

He leaned against the counter, panting. The hunger gnawed at him like a beast. He was stronger. Faster. But something inside was growing… hungrier.

He gripped the edge of the table.

Still worth it.

Always worth it.

---

Back at the Gym

Everyone had questions when he returned—with water and sealed food from the emergency lab stash.

"You good?" Damien asked. "You look pale."

"Just tired."

Another lie. But no one pushed.

Victoria eyed him again, then looked away, uneasy.

They ate. Rehydrated. Reorganized.

Then Evelyn, silent all this time, stood. "We need to leave soon."

"Why?" Ana asked.

"Because this place is a beacon," Evelyn replied. "The dead are drawn to noise. Smell. Life. It's only a matter of time."

She was right.

And that's when they heard it.

A banging. A cry.

Not a growl.

A human voice.

Everyone froze.

Riley rushed to the window and peeked out.

"There's people!" she shouted. "They're being chased!"

Leo stood instantly.

Damien grabbed a bat. "Let's move!"

They burst from the gym, weapons drawn. Down the ruined street, two teens—bloodied, terrified—were being chased by five zombies. One was crawling, but the others were fast. One had long arms like a mutated ape.

"Cover them!" Victoria shouted.

Leo dashed ahead. His movements were inhuman—too smooth. Too fast.

He slashed one clean through the head and shoved another off balance. Damien and Evelyn took the rest.

Within moments, the undead were down.

The two teens collapsed to their knees.

"Th-thank you…" one whispered, tears streaming down her dirt-covered face.

Miles handed them water.

They were survivors.

Leo looked at them.

More variables.

More distractions.

More XP.

He smiled kindly, but inside, the voice whispered again.

Grow.