They crossed the cavern floor, the ground uneven, littered with sharp volcanic rock and strange, crystalline formations that pulsed with a faint, sickly internal light. The groaning, hissing sounds of the ancient machinery grew louder as they approached the tunnel opening.
The tunnel was narrow, barely wide enough for them to walk single file. It sloped steeply downwards, twisting and turning. The air grew hotter, the metallic taste stronger. Faint red light flickered from somewhere ahead, casting long, dancing shadows.
After several minutes of claustrophobic descent, the tunnel opened into another vast chamber. But this one wasn't natural.
Massive, archaic machinery filled the space, pipes thick as tree trunks snaking across the floor and up the walls, glowing cherry-red in places. Pistons hissed, gears groaned, the entire chamber thrumming with barely contained power.
