The tea tasted like boiled rust.
Yang Yi sat cross-legged on the floor of his hut, the Thunder Drake sword laid across his knees. The Myriad Beast Assimilation Record sat on the low table between them, pulsing with a faint, rhythmic heat.
The blind Elder took a sip from a chipped clay cup. He made a wet, sucking sound that set Yang Yi's teeth on edge.
"You brewed this with sewer water," the Elder noted, not displeased. "Adds body."
"It's mineral water," Yang Yi said. His gold eyes didn't blink. "From the deep tap."
Lin stood in the corner, her back to the wall, a dagger hidden in her sleeve. She watched the old man like he was a bomb that had already started ticking.
"Who are you?" she asked.
The Elder set the cup down. He wiped his mouth with a sleeve that smelled of old parchment and mildew.
"Names are heavy. Call me Mo. I was the librarian before the current librarian. And the one before that."
He reached out a withered hand toward the book. Yang Yi's grip tightened on his sword handle. The scales on his forearm scraped against the leather grip.
Mo paused. "Relax, lizard. If I wanted the book back, I would have taken it while you were drooling on the floor of the Sump."
He tapped the cover of the manual.
"Do you know why this is forbidden?"
"Because it works," Yang Yi said.
"Because it eats the user," Mo corrected. "The author, a lunatic named Grandmaster Beast-King, didn't write a cultivation manual. He wrote a recipe. You aren't the cultivator. You're the soup."
Yang Yi felt a chill that had nothing to do with the drafty hut. The Blood-Root Lotus he had eaten felt suddenly heavy in his stomach.
"I stabilized it. I ate the Lotus."
"A bandage on a decapitation," Mo scoffed. "The Lotus binds the soul to the body. Good. But it doesn't stop the instincts from rewriting your brain. You feel it, don't you? The Wolf's rage? The Rat's cowardice? The Basilisk's sloth?"
Yang Yi didn't answer. He felt them constantly. A parliament of ghosts arguing in his head.
"You need a conductor," Mo said. "A dominant will. Or within a week, you'll just be a very strong, very stupid beast roaming the sewers."
"And you can teach me?"
"I can show you how to build the cage." Mo stood up. His joints cracked louder than Yang Yi's. "But first, I want to see what you found in the dark."
He turned his blind face toward the floorboards. toward the mine shaft deep below.
"I smell old blood down there. Ancient blood. Show me the door, boy."
The lift cage rattled as it descended.
It was a crude metal box suspended by chains, lowered by a winch system powered by the stronger Centipede thugs.
Yang Yi, Lin, and Elder Mo stood in the cramped space. The air grew hotter the deeper they went. The humidity spiked, turning the shaft into a sauna.
Yang Yi watched Mo. The old man didn't hold the rails. He stood perfectly balanced, swaying with the cage's erratic movements.
"You're not just a librarian," Yang Yi said.
"I swept floors. I dusted shelves. I watched generations of arrogant children march up the mountain and die." Mo smiled, revealing yellow, jagged teeth. "And occasionally, I fed the things they kept in the basement."
The cage hit the bottom with a bone-jarring thud.
Iron Hand Zhang waited for them. He looked nervous. The mine tunnel behind him was reinforced with new timber, but the rock groaned under immense pressure.
"Boss," Zhang nodded to Yang Yi, then eyed the old man. "Who's grandpa?"
"A consultant," Yang Yi said. "Show us the breach."
They walked past the exhausted miners. The men were huddled in alcoves, drinking water, looking pale. They weren't just tired; they were drained. The qi density down here was wrong. It didn't flow; it stagnated.
They reached the end of the drift.
The rock face had been cleared away to reveal a wall of smooth, black obsidian. In the center stood a circular door, twelve feet high, made of a metal that wasn't gold or iron. It looked like bronze that had been soaked in blood for a thousand years.
No keyhole. No handle.
Just a massive relief carving of a dragon curling around a human figure, crushing it.
And the seal.
A thick layer of red wax covered the seam of the door. It pulsed. Thump-thump.
"The Heart-Seal," Mo whispered.
He walked up to the door. He touched the wax.
Hiss.
Steam rose from his finger. He pulled it back, unbothered.
"This is the foundation of the Dragon Transformation Array," Mo said, his voice dropping to a reverent hush. "The entire sect... the floating islands, the arrays, the power... it all draws from what is behind this door."
"What is it?" Lin asked, stepping closer but keeping her distance from the pulsing wax.
"A battery," Mo said. "Or a prisoner. Depends on your perspective."
He turned to Yang Yi.
"The seal responds to bloodline. Pure Dragon blood opens it. Beast blood... might trick it."
Yang Yi looked at the door. The hunger in his gut—the Chimera's hunger—spiked violently. It wasn't just food. It was kinship. Whatever was behind that door felt like a lost limb waiting to be reattached.
"If I open it," Yang Yi said, "what happens to the sect above?"
Mo grinned. It was the smile of an arsonist holding a match.
"The flow is interrupted. The arrays on the peak will flicker. The protective formations will weaken."
"Chaos," Yang Yi muttered. "Perfect."
He stepped up to the door.
He didn't use a tool. He used his hand.
He sliced his palm with a claw. Black, heavy blood welled up. It sizzled on his skin, acidic and hot.
He pressed his hand against the red wax.
The door shuddered.
The carving of the dragon seemed to writhe. The wax absorbed Yang Yi's blood. It turned from red to black.
A mechanical groan echoed through the rock, deep enough to vibrate the fillings in Yang Yi's teeth.
"It accepts the offering," Mo cackled. "It thinks you're a hatchling coming home."
The wax melted, running down the door like tears.
The metal groaned. The door split down the middle.
It opened inward.
A blast of wind hit them. Not stale mine air. Ancient, metallic air. It smelled of copper and vast, empty time.
Yang Yi stepped into the threshold.
He raised the glow-stone.
It wasn't a room. It was a void. A massive, spherical chamber suspended in the hollow heart of the mountain.
And in the center, suspended by thousands of chains made of glowing light, was the source.
It wasn't a dragon.
It was a heart.
A colossal, desiccated heart the size of a house, beating slowly. Tubes of crystal ran from it, pumping glowing red liquid up into the rock ceiling—up toward the sect.
But the heart wasn't alone.
Attached to the bottom of the heart, like ticks on a dog, were pods. hundreds of them. Translucent, fleshy sacs.
And inside the pods were people.
Cultivators. Emaciated, unconscious, hooked up to the veins of the heart.
"The missing," Lin gasped, her hand covering her mouth. "The disciples who vanish during trials. The ones who 'ascend'."
"They don't ascend," Mo said softly, stepping up beside her. "They become fuel filters. The Dragon Heart's energy is too wild for the arrays. It needs to be processed through living meridians."
Yang Yi stared at the pods. He saw faces contorted in eternal agony.
He looked at the tubes pumping the refined energy upward.
"The sect isn't training us," Yang Yi said, his voice cold as the stone he was made of. "It's farming us."
He gripped the Thunder Drake sword.
"Zhang. Get the explosives."
"Boss?" Zhang looked at the massive heart, terrified. "If we blow this... the mountain comes down."
"Not the heart," Yang Yi said. "The plumbing."
He pointed to the crystal tubes carrying the energy upward.
"We're going to cut the supply line. If the Inner Sect wants power, they can come down here and bleed for it."
Mo laughed. A dry, rasping sound that echoed in the chamber.
"A siege," the old man said. "You want to starve the gods."
"I want to see them panic," Yang Yi said. "Then I want to see them fall."
He stepped onto the walkway leading to the heart. The chains rattled. The Chimera inside him roared, recognizing the scent of the apex predator.
He wasn't just a rat anymore. He was the cancer in the Dragon's chest.