The maintenance hatch groaned. Rust flakes rained down like dried blood.
Yang Yi slid the heavy iron grate aside. The smell hit them—ammonia, rotting meat, and something sweet. Metallic.
"Down the rabbit hole."
He dropped.
Water splashed his boots. The tunnel was cylindrical, lined with slime-slicked bricks. Luminescent moss clung to the ceiling, casting a sick, green pallor over the sewage.
Lin landed beside him. She covered her nose, gagging slightly.
"This isn't just waste. It's runoff from the Alchemy Hall."
"Means the rats are mutated. Stronger bones. Better cores."
Yang Yi scanned the darkness. The Dragon Token hummed a low, eager note against his hip. It liked this place. The concentration of energy here was higher than in the Dregs above. Filthy energy, mixed with toxins and discarded failures, but energy nonetheless.
"You need a weapon."
He kicked a pile of debris near the wall. A rusted iron bar, likely a broken grate support, rattled loose. He tested the weight. Two feet long, jagged end.
He tossed it to Lin.
She caught it, grimacing at the rust staining her palm. "I prefer balance."
"You prefer being alive. Stab with the pointy end."
They moved deeper. The water rose to their ankles, thick and oily.
Skittering sounds echoed from the pipes branching off the main tunnel. Hundreds of claws scratching against stone.
"They know we're here."
Lin tightened her grip on the iron bar. The air grew colder around her. She was instinctively cooling the immediate area to counter the humidity.
Red eyes appeared in the darkness ahead. Pairs. Dozens of them.
Needle-Rats. The size of dogs, with quills protruding from their mange-ridden backs.
The lead rat hissed, exposing yellow incisors dripping with venom.
"Formation," Yang Yi whispered. "I take the front. You flank the stragglers."
He didn't wait. He charged.
The rats surged forward, a tide of fur and teeth.
Yang Yi met the wave. He didn't have a sword, only his fists and the stolen knife from the thug in the forest.
He kicked the lead rat. The impact crunched ribs. The rat flew back into the pack, disrupting the charge.
Yang Yi slashed. The knife was short, forcing him to get close. He cut throats. He severed tendons.
A rat leaped for his neck.
He caught it mid-air. His hand clamped around its throat. The quills dug into his palm, drawing blood.
He didn't flinch. He squeezed.
Crunch.
He used the dead rat as a shield against the next attacker. Claws raked against the carcass in his hand.
Behind him, the air snapped with frost.
Lin moved with desperate grace. She side-stepped a lunging rodent, driving the rusted iron bar through its skull. She froze the wound instantly to prevent the spray.
"Glacial Step."
She slid on a patch of ice she created, closing the distance to a rat trying to circle Yang Yi. She skewered it.
The fight was ugly. No clean forms. Just mud, blood, and the screech of dying animals.
Yang Yi stomped on the last rat's head. Silence returned, heavy and wet.
He stood amidst the carnage, breathing hard. The beast blood in his veins sang. The pain in his hand from the quills felt distant, irrelevant.
He knelt by the largest corpse.
"Harvest time."
He sliced open the rat's chest. He dug his fingers into the gore and pulled out a small, irregular stone. It glowed with a faint, dirty yellow light.
A Beast Core. Low quality.
"Five points," he muttered, wiping it on the rat's fur.
He tossed it into his pouch.
Lin leaned against the wall, checking her boots for bite marks. She looked pale, her energy reserves dipping again. "There were too many. They weren't hunting. They were fleeing."
Yang Yi paused. He looked at the tunnel ahead.
She was right. The rats had been running toward the exit, not defending territory.
"Something scared them."
The water in the tunnel rippled. Not from the wind. From a vibration deep below.
Yang Yi looked down. The sewage wasn't just flowing; it was pulsing.
"The veins," he whispered.
He walked to a grate in the floor. The water drained into it.
He peered through the bars.
Below the sewer level, a massive, translucent pipe pulsed with crimson light. It wasn't sewage. It was liquid essence. Thick, refined, and powerful. It pumped rhythmically, like an artery.
And something was swimming inside the pipe. A shadow, vast and serpentine, moving against the flow.
"We aren't alone down here."
Yang Yi stood up. He looked at Lin.
"Grab the cores. Fast. We need to move before the landlord shows up."