Captain Halric dragged his stonesteel shield against the tunnel wall, not for balance, but because the sound of metal on rock was the only way he knew he was walking in a straight line.

The darkness down here wasn’t just an absence of light. It had weight. It pressed against the eyes, thick and absolute, swallowing the glow of the four luminescent lanterns his squad carried as if the air itself was hungry for it.

"Fifty paces," whispered the guide.

The guide’s name was Nym. That was what Halric called him, anyway. The Pallid didn’t use names the way surface-dwellers did — they used tonal frequencies that vibrated through the sinus cavities, impossible for a Human to replicate. Nym was pale to the point of translucence, hairless, eyes entirely pupil. His skin emitted a faint, pulsing blue-white bioluminescence that matched the patches of moss clinging to the ceiling.

"Hold line," Halric ordered. The command passed backward through the vanguard — twelve men, heavy infantry, marching in a two-wide column because the northern access tunnel wouldn’t permit three.

They were seventy hours out from the surface entrance. Seventy hours of stale air, descending gradient, and the constant, vibrating hum of the Morreth network that no one could quite explain. Behind them, a full kilometer back, the rest of the four-hundred-man garrison dragged modified supply wagons through the dark.

Halric’s squad was the edge of the spear.

"What do you hear?" Halric asked. He touched Nym’s shoulder. The Pallid’s skin was cold, like river clay.

Nym tilted his head — toward the solid rock of the eastern wall, not the tunnel ahead.

"Grinding," the guide breathed. The word sounded like a rusty hinge. "Beyond the natural fault. Teeth. High heat."

Halric unhooked the lantern from his belt and handed it to the soldier behind him. Varek, a veteran from the Ashwall garrison. Varek took it without a word and raised his shield.

"Formation," Halric snapped.

Twelve men locked shields right to left, filling the twelve-foot width of the tunnel in two ranks of six. Spears leveled over the stonesteel rims. Surface tactics, adapted for a place where you couldn’t flank and couldn’t retreat.

A ten-second silence fell over the tunnel. Heavy breathing. The scrape of a leather boot. The slow drip of condensation.

Then the eastern wall bulged.

It didn’t break immediately. It deformed, the solid stone glowing cherry-red for half a second before it exploded inward.

Halric raised his shield just as the shockwave hit — superheated fragments of rock rattled against the stonesteel like iron hail. The air in the tunnel flashed to a suffocating, arid heat.

From the glowing breach in the wall, something spilled into the corridor.

It wasn’t a dragon. Halric had seen the wyverns over Thalessa. This was something else. A segmented, wingless body, thick as a warhorse, covered in overlapping crimson plates that radiated visible heat. It had no eyes. Its head was a blunt wedge of fused bone ending in a circular maw of grinding, counter-rotating mandibles.

A Crimson Wyrm.

It thrashed in the confined space, mandibles chewing through the stone floor as it tried to orient itself. Behind it, a second wyrm poured through the breach, then a third.

They were scouting. Small ones — vanguard diggers, completely blind, operating on thermal and vibrational sense.

"Hold the line!" Halric roared. He didn’t need to worry about noise discipline anymore.

The first wyrm lunged — throwing its massive, armored bulk against the shield wall rather than biting. The impact threw Halric backward a half-step. His boots slid on the slick moss. The soldier beside him, a young recruit named Darris, took the brunt of the collision. The stonesteel shield held, but Darris’s shoulder popped out of its joint with an audible crack.

"Brace and thrust!" Halric drove his spear over the rim.

The stonesteel blade hit the wyrm’s crimson plating and sparked, glancing off. The armor was too dense, the angle too shallow.

The second wyrm surged over the first, using its pack-mate’s body as a ramp, and dropped directly into the second rank of soldiers.

Screams filled the tunnel. The heat was unbearable — the air burned Halric’s throat with every breath. He smelled roasting meat and didn’t want to look to see whose it was. They couldn’t hold this. Not in this space.

Behind them, pressed hard against the far wall, Nym let out a vibrating, high-pitched hum — pure panic. The Wyrm thrashed closer, its radiating blood-red plates searing the air inches from the guide’s face.

Nym slammed both glowing hands flat against the tunnel rock.

The bioluminescent moss on the ceiling flared — with growth, not light. Thick, fibrous tendrils exploded outward in every direction, dropping like a wet net over the wyrms. Fungal. Dense and spongy, rapidly expanding wherever it touched the heat of the creatures.

The fungal mass hit the first wyrm’s heat-radiating plates and instantly blackened, hardening into a carbonized crust. The wyrm shrieked — a mechanical, grinding sound — as the rapid calcification locked its segments together.

"Joints!" Halric yelled, seeing the plates separate slightly as the creature thrashed against the encrustation. "Hit the gaps!"

He drove his spear into the soft tissue between the armored neck segments, and this time the stonesteel punched through. Viscous, boiling-hot fluid sprayed back over his gauntlet. The wyrm convulsed violently and collapsed, its mandibles still clicking.

Varek, in the second rank, had abandoned his spear. He had his short-sword out, burying it to the hilt in the underbelly of the second wyrm while two other soldiers pinned it against the wall with their shields. The third wyrm — realizing the thermal signature of the prey was suddenly accompanied by calcifying death — tried to backpedal into the breach. 𝗳𝐫𝚎𝗲𝚠𝚎𝗯𝕟𝐨𝘃𝚎𝗹.𝗰𝗼𝗺

Halric didn’t let it. He stepped out of formation, grabbed a fallen spear from the ground, and vaulted onto the dead first wyrm’s back. He drove the second spear downward, putting his entire armored weight behind the strike, pinning the retreating creature to the tunnel floor.

It thrashed for thirty seconds, the heat slowly fading from its plates, before going completely still.

Silence rushed back into the tunnel, broken only by the ragged breathing of the squad and the hiss of cooling fluid on stone.

Halric pulled off his helmet. The air was thick with sulfur, cooked fungus, and blood.

"Report," he gasped.

Varek was kneeling beside Darris, strapping the young recruit’s arm tight against his chest. "Darris has a dislocated shoulder. Torv got a heat-lash across the face — second-degree burns. Everyone else is breathing."

Three enemy dead. Two wounded. For a Vanguard skirmish against divine creatures, they had gotten lucky. The fungal calcification trick had saved them from a slaughter.

Halric walked to the breach in the eastern wall.

The rock was still warm to the touch. The hole was roughly six feet in diameter, bored cleanly through solid granite by the wyrms’ mandibles. He held a luminescent lantern up to the opening and peered inside.

The tunnel didn’t meander. It didn’t wind like a natural cave or a foraging path.

It ran dead straight, sloping slightly downward, wide enough for a small army to follow.

Halric ran a gauntleted hand along the cut stone. He felt the deep groove marks left by the grinding teeth. The wall was smooth between the grooves — not smoothed by water or time, but polished by mechanical repetition, the way a millstone polished its bed. Whatever had cut this tunnel had done it in a single sustained pass. The stone hadn’t cracked or spalled. It had been consumed — ground to powder and either swallowed or expelled behind the creature as it advanced.

He pulled his hand back. The gauntlet was warm even through the leather inner lining.

He looked at the three dead creatures on the floor. Twelve outer mandible plates on the nearest one’s head, counter-rotating in pairs — when those were moving, the heat buildup at the contact point would be extraordinary. The granite dust would melt and resolidify behind the creature’s advance, sealing the bore. That explained the polished walls. That explained why the tunnel held its shape without timber supports.

These were not animals. They were machines shaped like animals, optimized by a war-god for a single function: advancing through solid stone toward a designated target.

Small ones. Scouts.

If scouts had dug this far, this fast, the main host wasn’t far behind. And they weren’t exploring. They were executing a trajectory.

He turned toward the Pallid guide. Nym’s bioluminescence had dimmed, his chest heaving from the exertion of manipulating the fungal growth.

"Nym," Halric said, his voice flat. "This trajectory. The line they’re cutting." He pointed through the breach, deeper into the dark. "Where does it lead?"

Nym looked at the breach. His large, pupil-less eyes reflected the faint blue glow of the lantern. His skin flickered — an erratic pulse Halric had come to recognize as terror.

"The singing stone," the guide whispered, his rusty-hinge voice trembling into the darkness. "Everything we have left."