Reborn with a Necromancer System-Chapter 221: The Underdark

Kai looked into the chasm's mouth. It held darkness, as if containing the stale air of millennia. The descent before them was carved out of layered stone, gnarled by time and roots that shouldn't have reached so deep. A faint blue glow pulsed from somewhere below, dim and eerie, as if the world itself was still alive down there…

Behind him, the high-pitched screech of a demon rang out from the distant ruins.

"And you're sure they won't follow us?" Kai asked, eyes not leaving the void ahead.

Seyren stood beside him, quiet for a moment. Then:

"Into the Underdark? Only the upper-ranked demons would bother… and over me? Probably not." His voice was calm, but Kai noticed the man's hand was on his dagger. Just in case.

Kai frowned. "And for a necromancer, a chronomancer, and an undead lich with ties to this world?"

Seyren gave a low, humorless laugh.

"I don't exactly know what those are, but I expect they would draw some interest. I would say the chances have increased... But it'll be harder for them to find us down here. Sound doesn't travel the same way. Smells are drowned out in the damp. Magic twists differently."

"Just go already," Vepice snapped, nudging Kai from behind. Her brow was tight with tension, but she wasn't panicking. Not yet.

Kai stepped forward and climbed down the slope. The air was colder, sharper. It smelled of damp stone, wet moss, and something more fungal, rotting, but alive. They descended through a narrow, rocky throat, walls slick with moisture and glowing algae. Then the passage widened.

It was like stepping into another world.

Before them stretched a vast subterranean landscape, layered in bioluminescent haze. Fungi of every shape and height dotted the terrain, some as small as buttons, others as tall as trees, their caps glowing with a ghostly light in shades of blue, violet, and green. A slow fog hung near the ground, swirling between their legs like silk.

The ceiling arched high above, barely visible except for the faint twinkle of crystalline growths.

The light emitted from clusters of shimmering quartz or perhaps something stranger, giving off a pale, ethereal light that washed everything in perpetual twilight.

Insects with glowing thoraxes buzzed lazily through the air, weaving between dangling roots and pale vines. Centipede-like creatures the size of small dogs scurried between rock crevices. In the distance, Kai spotted something the size of a horse crawling along the wall on all six legs, its shell iridescent, its antennae waving in slow, deliberate movements.

A river cut through the cavern far below, black and silent, with soft blue lights shifting beneath its surface. The source of the glow wasn't immediately visible.

'Perhaps luminous fish? Or maybe something less mundane...'

Chitin scraped against stone. Something clacked in the darkness.

"Stay close," Seyren said under his breath. "Down here, we're no longer the apex predators."

"I'm not really sure that humans are the apex predators on Muderan or Imeria, if I am being honest."

Orlin said nothing. His eyes were wide, not with fear, but recognition.

Awe, dread, and memories of the past filled his mind.

"This is it," the lich muttered, his voice distant. "The Underdark. The world beneath the world. My master once called it the graveyard of civilisations. Where the first necromancers came from. Where they learned to conquer death by watching how even light struggled to live here."

"Cheerful," Vepice muttered.

"The demons don't come down here," Orlin continued. "Not often. They don't like what waits in the deep places. They can't understand it. The madness here is older than them. The madness is what drove out the necromancers in the first place. But the things down here… they're simpler. Hungrier. And we can deal with hungry."

As they moved forward, Kai spotted a mushroom slowly turning toward them, its stalk bending unnaturally. As they passed, it straightened again, as if disappointed.

The stone beneath their boots glittered with veins of silver and something like glass. Strange plants grew between cracks—some folded closed like mouths, others unfurled only when Kai's shadow passed over them.

"This is beautiful," Vepice whispered.

Kai agreed. It was beautiful. In the way a dying star was beautiful. Vast, haunting. Dangerous beyond words.

"Where now?" he asked.

Seyren pointed toward a distant cluster of stone pillars and pale light.

"We camp in the hollow. I know the tunnels from there. We'll move while the predators sleep."

"And if they're not asleep?" Vepice asked.

Seyren smirked. "Then we pray they find something tastier than us. The acid that one of the big ones has will melt you to your bones."

And so they walked deeper, swallowed by a world no sun had ever touched.

Kai felt a subtle pressure building in his skull, like a creeping tightness behind the eyes. A sharp, sterile scent lingered in the air, metallic and bitter, laced with a sweetness that didn't feel natural.

Then the familiar, hollow tone of the system echoed in his mind.

[Mind-altering substances detected in the air.]

He blinked. His pace slowed. "…Oh."

Orlin turned to glance at him, one brow raised as he crouched beside the jagged stone wall. He was inspecting a strange bioluminescent creature no larger than a finger. Its translucent body pulsed with blue and green light, and it had claws like a tiny scorpion, clicking gently against the stone.

Kai tilted his head. "That must be the meaning behind the 'madness' you mentioned earlier."

"Hm?" Orlin stood, brushing his gloved hands on his robe. "Madness?"

Kai gestured vaguely around them, to the glimmering mist that swirled between the cave stalactites and the faint particles that shimmered like dust in sunlight. "There's something in the air. The system just warned me. It's… changing us. Not immediately. But I'm guessing the longer we stay down here, the more it'll twist our minds."

Orlin's brow furrowed in interest. "Ah. I wondered what gave this place such... character." His voice remained calm, as if he were discussing the taste of wine.

"So we're going to go crazy now too?" Vepice asked flatly.

Her voice was tired, edged with the rasp of someone who hadn't slept well in days. She leaned heavily on the wall as they walked, one hand brushing over the jagged surface to keep her balance.

"I don't think so," Seyren said without looking back. "I've been here many times. I'm fine."

Kai eyed him for a second too long.

Orlin chuckled. "Interesting. I wonder if that would have an effect on me."

They didn't get a chance to explore the topic further.

A shriek tore through the tunnels.

A shrill, insect-like noise that was so sharp it rattled through Kai's teeth.

A long, centipede-like creature lunged into view, its segmented body glistening with a wet sheen. Each of its legs ended in hooked claws, and its mandibles clicked open in a hungry display as it barreled toward them, fast as a serpent uncoiling.

Kai reached for his shadow.

But something else moved faster.

From above, with a rush of wind and an ear-splitting crack, a second creature landed, this one enormous and armoured, a grotesque hybrid of praying mantis and cockroach. Its front limbs sliced forward with uncanny precision, and the centipede's head was severed in a single blow.

The decapitated body twitched and spasmed as the mantis-beast began to eat.

A wet crunch. A low, vibrating chitter.

It turned its head toward them.

Its compound eyes, multifaceted and glimmering, fixed on the four humanoid figures watching from the stone path.

A long moment passed.

It didn't move. Just kept chewing.

"…Don't get any closer," Seyren said under his breath. "If it thinks we're here for a piece of its meal, it'll tear us apart."

They didn't argue.

Seyren gestured silently and veered off to the left, taking a smaller offshoot of the tunnel. The others followed in silence, the sound of bones snapping and organs squelching fading behind them as they descended deeper into the cave system.

---

Nearly half an hour passed in this silent, sloping passage. Shapes moved in the distance, but none drew close.

Finally, Seyren came to a stop.

He reached into the leather satchel slung across his chest and pulled out three objects: an orange, translucent crystal that shimmered faintly in the dark, a pale insect with frilled antennae still twitching faintly, and a root that looked half-rotted and fibrous.

Kai watched as he crushed the insect between his fingers, then snapped the root in two and mashed it into a rough paste against the stone. Finally, he took the crystal and cracked it open with a firm press between his boots. The shards glittered like ground-up amber.

Mixing the root and insect paste into the powdered crystal, he spread the mixture in a wide ring around their resting area.

A moment later, the air was filled with an eye-watering stench.

The scent was bitter, acrid, and tinged with something rotting and sour.

Kai gagged, covering his nose.

Vepice's face scrunched. "Gods. What is that?"

"Something most things down here avoid," Seyren said simply. "Almost nothing eats that root, it's poisonous even to most scavengers. The insect's scent repels predators. The crystal just amplifies it."

Kai took a breath, and immediately regretted it. "Why couldn't it repel with a nice, fresh pine smell?"

"No such luck," Seyren muttered. He stretched out on the flattest stone nearby. "We'll be safe here. Few things will come near this stink."

Vepice curled into a makeshift spot of her own, arms tucked beneath her for warmth. She tried not to breathe too deeply. Her eyes fluttered shut in sheer exhaustion, and despite the smell and the ever-present damp, she managed to slip into a restless sleep.

Kai sat nearby, cross-legged, watching the dark tunnel beyond their makeshift barrier.

Orlin remained standing, leaning against the wall with arms folded. His eyes, pale and glassy, seemed unfocused.

"You're not sleeping?" Kai asked.

Orlin gave a faint shrug. "It's not like the undead sleep. I'll keep watch just in case Seyren's little stew of horrors fails."

Kai nodded slowly and closed his eyes.

Not to sleep, but to rest.

In the silence, he listened to the sound of Vepice's breath, the distant clicking of something deep in the cave, and the soft, irregular dripping of water from above.

And for the briefest moment, he thought he heard something whisper in the stone.

But when he opened his eyes, there was nothing.

Only darkness, and the smell of things that had learned to survive in it.