Tunnels 02, Deeper

thought he glimpsed a reflection of his own face in the black-algae-encrusted glass, but as he looked closer, his spine tingled. No! It wasn't his reflection at all. It was a leached-white human head resting against the glass, its eyes hollow and its features eroded as if eaten away. He shuddered, moving on quickly, not allowing himself a second look.
    They rounded a corner at the end of the aisle, past a final tank, only to find the way blocked by massive slabs of broken concrete. The ceiling had caved in. But just as Cal was thinking they would have to turn back, Drake guided him into the darkness beside it, where the collapsed roof slanted down to a rough stairwell. It was bounded by a twisted, misshapen railing. They squeezed under the slab and, together, crept down the crumbling steps to where Elliott was waiting.
    The stench of decay that met them was far from pleasant. Cal assumed they'd reached the bottom when Elliott took a few more steps and waded into dark water. He hesitated, but Drake jabbed him sharply in the back until he reluctantly lowered himself in. The turgid warm water came up to Cal's chest. Dust and oily rainbows circulated as their movements disturbed the surface. Above them were radial growths of fungi, so thick and numerous that they had to be growing one on top of the other, rather like a coral reef.
    Tiny filaments hung from the fungi, glittering in Cal's light like a million spiderwebs. But the stench was overwhelming. He tried to hold his breath, but was eventually forced to draw the miasma into his lungs. It caught in the back of his throat, and he began to hack away.
    As he struggled to stifle the coughing, he looked down. To his horror, he could see movements just below the water's surface. He felt something tangle itself around his calf. Then it tightened.
    "Oh God!" he choked, and in a frenzy tried to dash through the water.
    "Stop!" Drake rumbled, but Cal didn't care.
    "No!" he shouted loudly. "I'm getting out."
    Surging forward, he saw Elliott ascending a set of steps in front of him. He caught up with her, clutching at a rickety iron banister that buckled under his weight. He managed to drag himself out of the fetid water. He was stumbling and tripping up the steps, banging his walking stick against the wall, desperate to get to clean air, when a hand grabbed him by the shoulder. It stopped him in his tracks, pressing agonizingly into his collarbone and spinning him around.
    "Don't ever pull a stunt like that again," Drake said in a low growl, his face just inches from Cal's and his uncovered eye burning with a fury. He shoved the terrified boy up against the wall, still gripping him by the shoulder.
    "But there was--" Cal began to explain, hyperventilating from both the foul air and his fear.
    "I don't care. Down here, a single stupid action can be the difference between us making it through this or not... It's that simple," Drake said. "Do I make myself clear?"
    Cal nodded, trying his utmost to stop his coughing as Drake prodded him on again. They came up into another corridor, with a much higher ceiling than the claustrophobic passage they'd just left. The sides angled outward and then in again toward the top, like an ancient tomb. The ground was damp, and every now and then Cal's boots crunched and cracked as if he was treading on glass.
    Soon they were passing openings that led off on either side from this oddly shaped gallery. They went a small distance into one before taking a turning off it into a substantial space that seemed to be divided into smaller areas. A maze of thick concrete partitioning reached halfway up to the ceiling, forming a whole series of pens. Strewn across the ground at the entrances to these pens were mounds of rubble and heaps of what appeared to be rusting metal.
    "What is this place?" Cal asked, daring to break the silence.
    "The Breeding Grounds."
    "Breeding... for what? For animals?" Cal said.
    "No, not for animals. For Coprolites. The Styx bred them to use as slaves," Drake answered slowly. "They built this complex centuries ago."
    He ushered Cal on before he could ask any more questions, into a smaller antechamber. It had the feel of a hospital ward. The floor and walls were covered in white tiles, now discolored with years of dirt and damp, and a huge number of beds were heaped haphazardly near the entrance, as if someone had been in the process of removing them but was interrupted halfway through. Strangely, the beds were, without exception,