The heat inside the chamber was blinding.
The crimson fire radiating from their crossed blades clashed against the freezing, suffocating weight of the Heart, filling the subterranean vault with a violent, roaring hiss of steam.
"The main cable!" Lily yelled, her hair whipping wildly in the thermal draft created by the burning silver. "In the center—under the main housing!"
Daniel followed her gaze.
Deep beneath the jagged, floating sphere of black star-steel, a massive bundle of iron-bound tendrils—thick as the trunk of an ancient oak—anchored the Heart to the bottomless pit of liquid iron below. Plugs of melted silver badges coated the entire surface of the anchor point, glowing with a sickening, pale light that tried to leech the warmth out of the room.
The mountain realized what they were doing.
The sphere shuddered. A wave of black, tar-like fluid erupted from the cracks in its surface, shooting toward them in jagged, needle-thin spikes.
"Hold!" Daniel roared.
He didn't pull back. He thrust his left arm forward, dragging Lily with him as they moved in absolute sync.
The crimson aura surrounding them flared outward like an expanding shield. When the black liquid spikes struck the red light, they didn't pierce—they instantly vaporized into clouds of gray soot that were swept away by the rising heat.
They reached the edge of the pit.
The heat rising from the liquid iron below was so intense it threatened to scorch the air right out of their lungs, but the crimson flow running through their veins kept their flesh from burning. The gray lines on Daniel's knuckles were completely gone, burned out and replaced by raw, living heat.
"On three!" Lily shouted, raising her blade high, her eyes reflecting the blinding crimson arc of her steel.
"No," Daniel said, his voice dropping into a steady, lethal calm. "Now!"
They drove their crossed blades deep into the central cable bundle.
The impact didn't sound like metal striking metal.
It sounded like a lightning strike hitting a frozen lake—a deafening, bone-shattering BOOM that sent a shockwave tearing through the chamber walls.
The black star-steel sphere shrieked.
The sound was unbearable, a chorus of thousands of lost voices crying out as the silver badges plugged into the Heart began to pop and shatter one by one. Bright, white-hot sparks erupted from the main cable, showering down into the liquid iron below.
The crimson energy from their blades flooded into the severed tendrils.
Like fire sweeping through dry wood, the red light raced along every iron cable snaking into the cavern walls. Wherever the light reached, the mountain's hold broke. The ancient armor, the shattered swords, and the black tar holding the tomb together began to crumble into harmless gray dust.
The main cable snapped.
The massive, jagged Heart of star-steel lurched upward, freed from its anchor, before plunging downward into the pit of liquid iron.
The mountain didn't collapse inward.
It exhaled.
A massive surge of pure, warm air rushed up from the deep pit, blowing past Daniel and Lily, carrying away the sulfur, the frost, and the century-old stench of decay.
Above them, the thick, unnatural vortex of ash clouds that had shrouded the highest peak for decades began to tear open. Bright, golden sunlight—real, warm sunlight—poured down through the roof of the cavern, cutting through the darkness like a brilliant sword.
Across the chamber, the tunnel leading back to the campsite was quiet.
Finn Foster stood at the threshold.
The pale, bone-like iron fused into his arms had completely dissolved, leaving only plain, scarred human skin behind. His milky, white eyes were flickering, the blank fog clearing to reveal steady, exhausted gray irises underneath.
He looked up at the sunlight breaking through the ceiling, a faint, disbelieving smile touching his lips.
"The seal..." Finn whispered, his voice warm and human for the first time in ten years. "...it's gone."
Daniel pulled his blade free from the ruined cable mount.
The black veins in the steel were gone, replaced by a smooth, polished sheen that reflected the bright daylight above. Beside him, Lily lowered her sword, letting out a long breath that no longer turned to ice in the air.
She looked at Daniel, her hand still locked in his.
"What now?" she asked softly.
Daniel turned his back on the ruined Heart and looked up at the sunlight streaming into the mountain.
"Now," Daniel said, "we go back to the academy, and we show them what happens when the leash breaks."