The party advanced into a narrow, dark corridor that opened into a massive cistern, its ceiling disappearing into darkness. The stinky air was thick with the smell of stagnant water and decay, making each breath feel heavy. A cumul of stone columns rose from the murky depths, their surfaces worn smooth by the passage of time. The water itself was dark and still, untouched for centuries, save for the faint ripples stirred by the party’s hesitant footsteps.

Dacite, her hooves sinking slightly with every step, led the way through the waist-deep water. "Stay close," she said, her voice tense but measured, echoing faintly through the walls and pillars. Her sharp eyes scanned the shadowed water before them.

Flake followed just behind, moving silently even in the sloshing waters, their sharp gaze darting between the columns. The oppressive silence in the cistern made every sound unnerving, each drip of water from the ceiling, each echo of their movements. They couldn’t shake the feeling of being watched, though the water revealed nothing beneath its surface. 

"Something’s wrong here," they muttered quietly. "Too quiet."

Cass trudged carefully through the murky water, his mind racing with worry. He could sense something more, something predatory, lying just beyond their sight. 

"This place isn’t just old. It’s... waiting for something." His voice was low, filled with dread.

Darling, splashed along with the others, though the water lapped higher around his legs than he’d have liked. He gave a nervous chuckle, glancing warily at the pitch-black depths beneath him. "Remind me again why all these ancient dungeons need creepy chambers?"

Before anyone could respond, the water around them seemed to tremble, just for a moment. A faint noise cut the silence like a knife. Everyone froze, their breaths catching in their throats. Then, from somewhere far ahead, there came a louder sound, a heavy splash, something large displacing the water with force.

Cass’s blood ran cold. "Did you hear that?"

The water’s surface bulged, as if something massive was rushing beneath it, disturbing the calm in an unmistakable surge. Whatever it was, it was moving fast, straight toward them. 

Dacite raised her voice, eyes narrowing as she scanned the water. "Get ready!" she yelled. "We’re not alone."

The rushing sound grew louder, accompanied by a low groan that echoed through the columns like a beast awakening. The dark water seemed to rise in front of them, disturbed by the sheer size of whatever creature lurked beneath. 

Darling stumbled back, his usual bravado faltering. "What the hell is that?" he breathed, eyes wide as the water began to churn violently.

A shape, massive and slippery, broke the surface in the distance. The faint light reflecting off the water barely caught its grotesque form, but the glimpse was enough to chill the party to the bone. Its ridged back and long, serpentine shape moved with terrifying grace, too quick for something of its size. 

Flake was already moving, eyes darting toward the nearest column. "We need higher ground!" they called, pointing toward a broken platform rising just above the waterline.

Dacite didn’t hesitate. "Move! Go!" She lunged forward, splashing through the water as the others followed her lead. The creature’s path was clear now, its immense body causing waves to break against the stone pillars, its approach unavoidable. 

They reached the base of the platform, each of them scrambling to pull themselves up from the water. Flake was the first to leap onto the slick stone, before helping Darling up just as the creature swam closer. 

The water exploded behind them as the monster breached the surface, revealing its full, horrific size. Its massive, scale-covered head rose from the cistern’s depths, eyes glowing faintly in the darkness. A jaw lined with jagged teeth opened wide, letting out a guttural roar that shook everything. It lunged toward them with terrifying speed, nearly knocking them off balance.

Breathing heavily, the party stood on the unstable platform, their eyes fixed on the creature as it circled below, its eyes gleaming hungrily. 

Cass wiped the water from his face, gasping for breath. "That thing... it’s not just a beast. It’s been bound here—part of the dungeon’s defenses."

Darling shook his head, still trying to catch his breath. "Fantastic. A giant, enchanted water serpent guarding a cistern. Just what we needed."

Flake was already scanning the area, their keen eyes catching sight of an exit on the far side of them. "There," they said, pointing toward a narrow staircase winding up into the darkness. "But we’ll have to get past that thing."

The creature’s massive body rippled through the water again, the columns shaking as it swam in tight circles, watching, waiting for them to make their next move.