The pool chamber was quiet in the hours after the fight with the undead wizard and his zombies, save for the gentle lapping of water against pale stone. The pool lit the ancient hall from below in soft, undulating ripples of turquoise and silver, casting long shadows across carved runes that had not seen light in three centuries.

Garnel Stoneblender sat cross-legged by the water’s edge with his grandmother Mala’s leather journal open on his knees, surrounded by his ticking copper callipers and brass measuring lenses. Charcoal dust smudged his nose, and his wild mop of bright red hair stuck out in all directions, but behind his round spectacles, his eyes darted with bright wonder.

“The magic isn’t gone,” Garnel whispered, not looking up as Derek walked over. “It was only sleeping. The reservoir draws from deep veins beneath the plateau, but the ancient conduits flow east. There are more chambers beyond the fallen wall — sockets, altars, whole galleries.”

Derek looked at the far end of the room, where tons of shattered granite blocked the eastern archway in a mountain of rubble. “That wall didn’t come down by accident.”

“No,” Garnel agreed cheerfully, flicking a scrap of parchment. “Someone wanted to make sure whatever lay beyond stayed put. Or perhaps they were trying to keep something out.”

Behind them, propped up against a stone pillar where Nibbles and Derek had dragged him down from the stairs, sat the stiff zombie they had hauled along. He was clad in ancient, peat-stained leather armour that smelled strongly of damp compost and wet ditch-water.

“He’s still remarkably intact,” Nibbles said, nudging a muddy boot with his toe. “Frightful dress sense, but sturdy bones. I’m calling him Poopy Joe. He looks like he fell backward into a farmer’s muck-heap fifty years ago and never got around to getting out.”

Dave looked up from his spellbook, eyebrows raised. “You’re giving names to the undead now?”

“He has character,” Nibbles insisted, crossing his arms. “And he’s not doing anything else.”

Garnel looked over his spectacles, eyes twinkling as he examined the stiff zombie. “The pool’s waters carry restoration, but Ethium magic is complex. If we can understand how the ancient wizard bound him, perhaps the pool’s energy can cleanse the decay and restore his motion… but it will take time and careful study of Grandmother’s notes.”

“Take your time,” Nibbles said, leaning Poopy Joe securely against the stone pillar. “Just don’t let him wander off.”

---

They set watches by turn that night, the pool’s light painting the ceiling in slow, liquid waves.

It was during Dave’s watch, near three in the morning, that Loki’s ears flattened. The dog let out a sharp, breathless huff and stood up, his snout pointed toward the upper spiral stairs.

“Thorn,” Dave whispered, touching the fighter’s shoulder.

Dark figures slipped silently down the winding stone stairs — not just survivors from the tower camp above, but fresh Hammer thugs and archers reinforced by other squads across the plateau, seeking revenge under cover of night. It was clear the Hammers had established a far wider foothold on Ethium than anyone had guessed. At their head moved a tall, thin figure wrapped in a dark, trailing cloak that seemed to swallow the lantern light.

“Hammers!” Thorn shouted, shield coming up just as an iron arrow ricocheted off his shoulder plate with a loud ping.

The chamber erupted into noise. Derek was on his feet in an instant, mace drawn, while Loki charged the lead archer with a fierce bark. Dave raised his staff, hurling a bolt of crackling orange fire across the water that caught two thugs in the doorway.

Through the chaos, Thorn saw the cloaked figure pause at the edge of the stairwell. Cold, calculating eyes gleamed beneath a deep hood. The stranger spared one long look at the glowing pool, turned on his heel, and melted back up the dark spiral stairs.

While the Hammers fight, their cloaked leader watches the pool — then slips back into the dark.

“Stop him!” Derek yelled, striking down a thug who lunged toward Garnel.

Thorn bounded across the room, but the remaining Hammers threw themselves into the bottleneck to cover their leader’s retreat. By the time Thorn and Derek cut their way through and reached the landing, the cloaked watcher was gone into the dark of the plateau, leaving only cold night wind howling through the tower ruins above.

---

The next morning, the companions gathered by the eastern cave-in armed with heavy iron pitons, picks, and crowbars taken from the Hammer camp.

“The wizard’s notes are clear,” Garnel said, adjusting his spectacles as he handed over a rough sketch of the wall. “The central conduits run through this wall. We must see what lies beyond.”

It took two full days of hard, backbreaking labour. Thorn and Derek levered massive granite blocks aside while Dave and Nibbles cleared the heavy gravel and hauled away baskets of rubble. By the second afternoon, a narrow gap opened near the ceiling, barely wide enough for a small bird.

Dave nudged Peggy from his shoulder. The pseudodragon familiar unfurled her leathery wings, squeezed through the dusty gap, and glided into the dark beyond. For a moment there was only silence — then a soft, satisfied chirp echoed back through the stone.

“Peggy says it’s clear,” Dave reported, closing his eyes to share her vision. “Smooth walls, tall arches. Safe to cross.”

Nibbles squirmed through next, followed by Dave, Derek, Thorn, and a wide-eyed Garnel clutching his parchment folders tightly.

“It opens up!” Nibbles called out. “Smooth walls! Ethium work!”

Beyond the collapse lay a grand Ethium corridor, its pale marble blocks smooth and perfectly joined. Fifty yards down, the hallway expanded into a high, vaulted gallery lined with ancient statues.

At the near end stood carved figures of Ethium citizens in long, flowing robes. At the far end stood stoic dwarf lords carved from dark granite. Lined between them along the walls were eight towering warrior statues carved from pale, veined stone, each holding a massive halberd.

Many of the carved wall sockets above their heads stood dark and empty, their stones lost or looted centuries ago. But above three of the pedestals, pale blue Ethium Stones pulsed with dormant light.

As Thorn stepped onto the central flagstone, a loud mechanical click boomed through the hall.

The three warrior statues with stones in their sockets turned their heads in unison. Their stone eyes flared with pale light as they stepped off their pedestals with a thunderous thud that shook dust from the ceiling.

“Guards!” Derek warned, drawing his weapon as Garnel squeaked and ducked behind him. “Border sentries!”

Thorn met the lead statue head-on, his battleaxe striking its stone arm with a sharp rang — but the iron blade left only a faint scratch. The guardian swung its heavy halberd in a broad arc, battering Thorn back against the wall.

“Iron won’t bite them!” Thorn grunted, barely catching the next crushing blow on his shield.

Nibbles ducked under a swinging stone axe, stabbing uselessly at a statue’s leg. “It’s like trying to fight a mountain!”

Dave ducked behind a pillar, his eyes scanning the gallery wall. “The stones in the sockets! They’re powering them! We need to pry them out — but don’t break them! We need those stones intact!”

Three ancient border guardians step down from their pedestals — and the party discovers what powers them.

Derek raised his mace. “Thorn, hold the line!”

While Thorn and Loki drew the guardians’ fury, Nibbles scrambled up the nearest pedestal. Dodging a stone elbow, he jammed his dagger tip under the first Ethium Stone, popping it loose. He lunged sideways as it fell, catching the glowing stone cleanly in both hands before it could shatter on the floor. The statue looming over Thorn went instantly stiff, its eye-light dying as it froze into an inert monument.

Working quickly, Derek used his mace handle to lever out the second stone, catching it in his heavy mail gauntlet. Dave cast a spell of kinetic force to pop the third stone free, guiding it safely through the air into his waiting palms.

One by one, the three stone guardians fell silent until the gallery was still again.

“Not bad,” Nibbles said, holding up the unmarred stone with a grin. “Tricky catch, but definitely shiny.”

---

Beyond the Hall of Statues, the corridor ended abruptly at a terrifying precipice.

The ancient Ethium bridge that once spanned the vast underground abyss had collapsed long ago, its broken stone spans hanging over empty air. The cavern opened up into a dizzying subterranean vault — a sheer 50-foot vertical drop from the corridor ledge straight down into the pitch-black lake basin below. High up on the opposite cliff face, seventy feet across the gap and fifty feet above the dark floor, a narrow archway marked where the corridor continued into the deep.

Thorn anchored two heavy ropes to a sturdy stone pillar. But Garnel took one look over the edge, went pale, and backed away clutching his notes.

“I… I shall stay up here at the ledge,” Garnel stammered nervously, peering down the 50-foot drop. “I can guard the ropes and watch your descent!”

Thorn nodded, and the four companions abseiled down the sheer cliff face into the damp, echoing shadows below.

The cavern floor was a nightmare of shattered rubble, slick stalagmites, and a slow-moving, pitch-black lake fed by a trickle of water from the ceiling. Near the base of the western cliff was a foul, stench-choked cave mouth heaped with rotting carcasses and decaying rubbish.

“Phew!” Nibbles gagged, holding his sleeve over his nose. “What in the seven hells is that smell?”

“Foul refuse,” Derek said grimly, inspecting the pile of rotting bones beneath the cave mouth. “Looks like whatever lives up in those upper tunnels uses this cavern as a dumping ground.”

Dave took a step toward the edge of the black lake, his torch casting long, orange flickers across the water. Suddenly, a soft, sorrowful voice echoed inside his mind — clear, pathetic, and desperate.

Please… help me… the voice whispered in Dave’s head. I am trapped beneath the stones… so cold…

Dave blinked, taking another step closer to the water’s edge. “Someone’s down there… trapped in the water…”

“Dave, wait!” Derek warned, reaching out to grab his shoulder. “Don’t go near the edge!”

Before Dave could step back, the dark water exploded upwards. A colossal, rubbery body five feet across erupted from the sludge, supported by three thick, stumpy legs. Two massive, muscular tentacles crowned with spiked suckers lashed out, catching Nibbles around the waist and hauling him off his feet with a terrified yelp.

“Otyugh!” Derek roared, drawing his mace.

The black lake erupts — and Nibbles is dragged towards the Otyugh’s maw.

“Form up!” Thorn barked, charging across the slick rocks with shield raised. “Derek, flank left! Dave, hit it with fire!”

The creature’s central maw opened — a gaping nightmare lined with three rows of yellow teeth. It dragged Nibbles toward its mouth, biting deep into his shoulder armour.

“Get off me, you oversized turnip!” Nibbles screamed, flailing frantically with his dagger.

Thorn closed in fast, keeping his shield raised to deflect the creature’s second lashing tentacle. Swaying under a crushing sweep, he swung his battleaxe in a powerful one-handed chop across the tentacle holding Nibbles. The blade bit deep into the rubbery hide. The beast let out a wet, gurgling screech of pain, releasing Nibbles into the black mud.

“Fall back, Nibbles!” Thorn commanded, stepping squarely between the thrashing monster and the rogue before its free tentacle could snare him in turn. “Dave, NOW!”

Dave raised his staff, hurling a bolt of fire, while from fifty feet above, a second streak of bright orange flame shot down from the cliff top! Garnel was leaning frantically over the ledge, peering through his spectacles and firing Fire Bolts down into the lake basin!

“Take that, you foul beast!” Garnel squeaked from high above.

The combined spellfire erupted over the creature’s rubbery back, filling the cavern with the smell of scorched sludge. Derek rushed into the shallows, his mace glowing with divine light as he struck the monster’s flank.

The Otyugh thrashed wildly, sending black water splashing thirty feet into the air, before collapsing back into the lake with a heavy, gurgling splash.

Silence returned to the cavern, save for the sound of Nibbles coughing up mud.

“Is everyone alive?” Thorn asked, pulling Nibbles out of the shallows.

“Barely,” Nibbles wheezed, rubbing his bruised ribs. “I tasted that thing. It tastes like rotten cabbage and regret. Nice shooting from up there, Garnel!”

Once the party climbed back up the ropes to the corridor ledge, Garnel wiped sweat from his brow, still trembling slightly as he looked back toward the abyssal drop.

“That… that was far too close,” Garnel admitted, adjusting his spectacles with shaky fingers. “Steep drops, animated sentries, giant lake monsters… I think everything further on is a bit too scary for me. If it’s all the same to you, I shall return to the pool chamber. I can study the dead wizard’s notes in peace, clean up the chamber, and monitor the stone resonance while you explore ahead.”

“A sound plan,” Derek agreed with a warm nod. “The pool is safe now, and we’ll know where to find you.”

Searching the muck near the troglodyte chute, Derek spotted a rusted iron chest wedged between two rocks — the remains of some long-forgotten adventuring party. Inside, protected by oiled leather, they found a pouch of silver coins and a small glass vial filled with glowing red liquid.

“A healing potion,” Derek said, handing it to Thorn. “We’ve earned it.”

They turned toward the eastern cliff, where a steep stone stair cut into the rock face led up toward the high corridor — and the dark, unknown halls of the Duergar.