The tunnel was quieter now.
Too quiet.
Lucas's boots dragged against the stone as he walked, every muscle screaming for rest. The air was thick with dust, the veins on the walls flickering faintly, still unsettled from the battle behind him. He glanced over his shoulder once — the path he came from was swallowed by darkness.
The Reaper's Hook scraped along the floor, leaving a faint metallic echo that faded too quickly.
He didn't know how long he'd been walking — minutes, maybe hours — when the ground trembled beneath his feet.
A low, rhythmic vibration rolled through the rock. It wasn't like the tremors from before; this one had a pulse. It almost felt like the earth itself was breathing.
Lucas froze. "That's new," he muttered.
The veins along the walls began to flicker erratically — their blue glow fading in and out, like dying firelight. A faint hum pressed at his ears, deeper than sound. The same kind of pressure he'd felt when the corrupted creature screamed before it died.
He frowned and turned toward where the rumbling came from — back the way he'd come.
"Nope," he said under his breath. "Absolutely not."
He looked ahead. The tunnel began to branch: one path rising upward toward a faint hint of airflow, the other sloping deeper into the earth, where the veins shimmered not blue but pale gold.
He stood at the split, chest tightening. Up meant people, maybe food, maybe answers.
Down meant more monsters, more glowing nightmares, and a growing whisper in his head that wouldn't shut up.
He stared into the golden light until it seemed to pulse with his heartbeat. Then he shook his head.
"Not today. I'm not suicidal enough today."
He turned toward the upper tunnel — and that's when he heard the sound.
A hum. Deep, resonant, coming from behind him.
The same iron door he'd passed earlier was singing.
The hum grew louder, swelling through the rock until the air itself seemed to vibrate. Lucas stumbled, clutching the wall. A hairline crack ran through the stone near the door, glowing faintly gold. Then, with a shuddering groan, a pulse of energy shot outward.
The force slammed into him like a shockwave. He hit the ground hard, sliding across the stone. Sparks of blue light scattered from the walls before fading to nothing.
"Okay," he gasped, pushing himself up, "that's officially above my pay grade."
He squinted back toward the door. It had opened — just a few inches.
A thin line of light spilled through the gap, cutting through the dust. It wasn't the cold, sterile blue of the veins. This light was warm. Golden. Alive.
He couldn't look away.
Inside the gap, something shifted. Not fast — not aggressive. It was the slow, heavy rhythm of something enormous moving in its sleep.
He swallowed. "Hello?"
His voice came out small, lost in the hum.
Nothing answered.
He took a hesitant step forward, curiosity fighting with survival instinct. The light washed faintly over his skin, and for a second, it didn't feel threatening. It felt almost… comforting.
Then the whisper came again.
Not in his ears this time — inside his head.
"The heart remembers… come closer."
Lucas froze. Every muscle in his body went rigid. "Nope," he whispered. "Absolutely not."
He started backing away, one careful step at a time, eyes never leaving the door.
"Come closer."
The voice was patient, gentle, and impossibly ancient — like it had been waiting for him for a long time.
He shook his head hard, turned, and ran.
The golden light flickered once behind him, as if disappointed.
He followed the upper tunnel until the air shifted — cooler, carrying hints of open space. The faint echo of voices reached his ears. Human voices.
For the first time in what felt like days, he let himself hope.
"Please be real," he muttered, half-running, half-limping.
The tunnel opened into a larger corridor reinforced with wooden beams. A handful of figures moved through the haze — flashlights, gear, voices calling names.
Then he heard his own.
"Lucas?!"
Ryn's voice.
He blinked through the dust, grinning. "You're either real or my brain finally gave up."
Ryn rushed forward, followed by Barek, his mechanical arm glinting in the light.
"Holy hell," Ryn breathed. "You're alive?"
"Define alive," Lucas said, slumping against the wall. "If you mean still moving and complaining, then yeah."
Barek looked him over, then noticed the bundle of crystals hanging from his belt.
"Where did you get those?"
"Long story short," Lucas said, "I accidentally won a fight with a glowstick zombie."
Barek took one of the shards, holding it to the light. The thing pulsed faintly in his palm.
"That's… impossible. Corrupted cores don't solidify — they melt through steel."
"Well," Lucas said, "mine didn't get the memo."
Before Barek could reply, a sharp voice cut through the tunnel.
"Report."
Captain Vorn stepped out of the shadows, her coat streaked with soot. Her expression was unreadable until her eyes landed on Lucas — then softened, just for a heartbeat.
"You survived," she said quietly.
"Barely. Can't say the same for the décor down there."
Her gaze shifted to the golden flicker still faintly visible down the tunnel behind him. For the first time since he'd met her, she froze.
"No," she murmured. "Not again."
Ryn frowned. "What's down there?"
Vorn didn't answer right away. When she finally spoke, her voice was colder than the stone around them.
"Something that should've stayed asleep."
She turned to Barek. "Seal the lower levels. No one goes past the breach."
Barek nodded grimly and signaled his crew.
Lucas looked back one last time. Through the haze, the faintest line of gold still glowed beneath the sealed doorway.
Whatever was behind it hadn't gone dormant — it was waiting.
The trip back to the Holdfast was silent. Even Ryn didn't try to joke.
The air grew cleaner, brighter, but the hum never fully left the stone. Every few steps, Lucas could feel a vibration underfoot — subtle, rhythmic, matching his own pulse. It wasn't his imagination. It was the veins themselves.
When they finally reached the main gate, the others moved ahead to report. Lucas lagged behind, exhausted. His fingers brushed against his pocket — the one holding the corrupted crystals.
They were warm.
He stopped and pulled one out. The shard pulsed faintly in his hand, threads of gold winding through the dark glassy surface. It almost seemed… alive.
Then, for just a moment, text flickered faintly before his eyes — a whisper of blue against the dim light.
[Quest Updated: The Heart Below – Status: Dormant]
He blinked. "Dormant," he murmured. "Good. Let's keep it that way."
He shoved the shard back into his pocket and walked toward the Holdfast's gates.
Behind him, deep in the sealed tunnel, the iron door pulsed once —
a single golden heartbeat beneath the stone.