The world did not smell like magic anymore. It smelled of sulfur, burning coal, and the copper tang of old blood.
Kael Light adjusted the brass goggles over his eyes, the leather strap digging into the scar tissue at his temple. He sat hunched over a drafting table that was too small for a man of his size, though he was half the man he used to be. The stump of his left arm throbbed in rhythm with the rhythmic thump-hiss of the steam pistons driving the refinery below.
"Unit 734," a voice rasped from the doorway. "Baron Vance is waiting for the efficiency report."
Kael didn't look up. He picked up a charcoal stick with his remaining hand—his right hand, the one that used to hold a staff, now stained permanently black with soot—and drew a sharp line across the schematic of the pressure valve.
"Tell the Overseer the flux-capacitance is off by twelve percent," Kael said, his voice rough from the smoke that perpetually hung in the air of the Fire-Islands. "If we increase the pressure now, the boiler plating will shear. I need another hour to recalibrate the governor."
The guard, a man encased in crude, bulky steam-armor that leaked grease onto the stone floor, grunted. "You have thirty minutes, cripple. Then the Baron wants you in the Observation Deck."
The heavy iron door slammed shut. The lock clicked—a complex tumbler mechanism Kael had already mentally dismantled a dozen times.
Kael exhaled, blowing a cloud of coal dust off the parchment. Thirty minutes.
He stood up, his knees popping. He was thinner than before. The muscle of a warrior had been replaced by the lean, wire-tight tension of a survivor. He wore the grey rags of a senior engineer-slave, distinguished only by the heavy iron collar around his neck. It didn't suppress magic—there was no magic left to suppress—but it contained a small vial of nitroglycerin. If he crossed the perimeter, or if the Baron pressed a button, Kael Light would lose his head.
He walked to the window of the Design Tower.
Below him, the prison colony of Cinder sprawled across the volcanic island like a festering wound. Great iron pipes veined the landscape, carrying magma from the volcano's heart to the massive refineries that processed it into Ignis-Fuel. Thousands of slaves moved like ants in the red glow, hauling carts, hammering rivets, dying in the heat.
Kael pressed his hand against the cold glass. Physics, he thought. Simple leverage. Thermal expansion. Pressure.
They thought they had broken him when they took his arm. They thought they had neutered him when the Progenitor fell and the mana streams dried up. But Baron Vance, for all his genius, had made a critical error. He had looked at Kael and seen a healer.
He didn't know that a healer was just an engineer of the body. And an engineer knew exactly where to push to make a system collapse.
Kael turned back to the schematic. It was a drawing of the primary release valve for Sector 4—the volcano's main vent. To the untrained eye, Kael's adjustments looked like optimization. He had widened the intake shafts, ostensibly to increase flow.
In reality, he was removing the safety redundancies.
He picked up the charcoal stick again. With precise, deliberate strokes, he altered the curvature of the steam-release flange. By his calculation, once the pressure hit critical mass during the Emperor's inspection next week, the flange wouldn't just vent steam. It would direct the blast backward, into the structural supports of the Design Tower itself.
He wasn't building a better engine. He was building a bomb the size of a mountain.
A soft knock came from the ventilation grate near the floor.
Kael froze, then tapped his foot three times. Two shorts, one long.
The grate slid aside. A pair of eyes, bright and terrified, peered out from the darkness of the ducts. It was a child, no older than eight, covered in soot so thick he looked like a shadow.
"Engineer," the boy whispered. "The Lady Isolde sent me. She says the Hive is humming."
Kael's pulse spiked. The Hive. That was the code for the women's barracks. "Is it ready?"
"She says the Lantern is lit," the boy replied, reciting the message. "And the Big Man has the tool."
Adam. The thought of the Progenitor wielding a wrench instead of a universe-shaping spell still felt absurd, but Adam took to manual labor with a terrifying, stoic efficiency.
"Good," Kael whispered, reaching into his boot. He pulled out a small, folded piece of paper—a diagram of the ventilation shafts he had mapped over the last six months. "Give this to her. Tell her Sector 4 goes critical in five days. If she's not at the docks by the second whistle, she burns with the rest of us."
The boy snatched the paper with a nod and vanished into the dark. The grate slid back into place just as the heavy lock on the main door began to turn.
Kael was already back at his desk, the charcoal moving smoothly across the paper.
The door swung open. This time, it wasn't a guard.
Baron Vance filled the doorway. He was a gaunt man, wearing a pristine white lab coat that seemed impossibly clean amidst the filth of Cinder. Half of his face was covered by a monocle apparatus that whirred and clicked as it zoomed in on Kael's work.
"Unit 734," Vance said, his voice smooth and cold, like oil on polished steel. "My guards tell me you're delaying my test."
"Optimizing, My Lord," Kael corrected, not looking up. He kept his tone servile, flattened. "The thermal variance in the magma flow was higher than anticipated. If we ran the test now, we'd lose 4% efficiency in the turbines."
Vance walked into the room, the heels of his boots clicking on the stone. He stopped behind Kael, looking over his shoulder. The mechanical lens on his face spun, magnifying the drawing.
"4%," Vance mused. "Acceptable losses for progress, wouldn't you say?"
"Not if the turbine blades warp," Kael said, pointing to the diagram with his blackened finger. "Then you lose the whole sector for a month. And the Grand Artificer won't be pleased if the quota drops."
Vance went stiff at the mention of the Grand Artificer. Kael knew exactly which buttons to press. Fear of the capital was the only thing stronger than Vance's ego.
"You have a sharp mind for a savage, 734," Vance murmured, leaning closer. He smelled of ozone and peppermint. "It's a pity about the arm. You might have made a decent scientist in another life."
Kael stared at the stump of his left arm. The phantom pain flared, a reminder of the day the magic died.
"I serve the machine now, My Lord," Kael lied.
Vance chuckled, a dry, rattling sound. "Yes. We all do. The machine requires fuel." He straightened up, smoothing his coat. "Finish your calculations. The test proceeds at dawn. If the turbine warps, I will have your other arm."
Vance turned and swept out of the room, his guards trailing behind him.
Kael waited until the footsteps faded down the corridor. He looked down at the schematic. The changes he had made were subtle, buried in the math. But at dawn, when they fired the main intake, the vibration wouldn't warp the turbine.
It would crack the containment seal on the sub-level. Just a hairline fracture. Enough to start a leak that wouldn't be detected until it was too late.
Kael dropped the charcoal. He looked at his hand—the hand that used to knit flesh and bone with a thought. Now, it was covered in graphite and grease.
He clenched his fist.
"Let it burn," he whispered to the empty room. "Let it all burn."
He picked up the eraser and removed the safety margin from the blueprint.