At the absolute lowest point of the inverted Spire, hanging directly over the churning magma lake, sat the Launch Cradle.
Resting in the cradle was the Core Transit Pod—a sleek, twenty-foot needle forged from solid tungsten-carbide, designed to withstand the crushing pressure and electromagnetic radiation of the planetary mantle.
"The launch clamp is manual!" Sorsha shouted, pointing toward a catwalk overlooking the pod's magnetic rail. "The automated sequencer died when the cables tilted!"
Behind them, the reinforced blast doors of the launch deck buckled inward.
A heavy breaching charge detonated, blowing the steel doors into shrapnel. Through the smoke strode Commander Cassian Graven, encased in a massive, black-enameled powered assault suit equipped with shoulder-mounted missile pods and a heavy kinetic pile-driver arm.
Behind him were twenty Hive shock troopers.
"Calder!" Graven's voice boomed through the suit's external speakers. "You have reached the bottom of the world! There are no more trains! There are no more towers to collapse!"
Sorsha looked at Idris, then at the heavy rotary machine gun mounted to the catwalk railing.
"Get in the needle, Calder," Sorsha said, her jaw setting into hard, scarred lines.
"Sorsha—"
"I told you I had eighty families in the lower pods," she snapped, racking the heavy gun's charging handle. "They already evacuated on the western service line. Now I'm balancing my ledger. Get in the damn pod and finish this."
She turned the heavy machine gun toward the doorway and pulled both triggers, unleashing a deafening hail of armor-piercing fire into Graven's vanguard.
The roar of Sorsha's rotary gun ceased abruptly.
Graven's powered exosuit smashed through her barricade like cardboard. The heavy hydraulic pile-driver arm struck Sorsha's chest, hurling her broken body over the gantry railing. She plummeted into the darkness of the lower rift, crashing onto an emergency maintenance net suspended hundreds of feet below, motionless and lost to the shadows.
Graven turned toward the transit pod, his armor dented and smoking, his optical visor glowing crimson.
"Calder!" Graven bellowed, his hydraulic joints whining as he closed the distance with long, thunderous strides.
Idris stepped out onto the narrow boarding plank, putting himself between the Commander and the pod's open hatch. "Get inside, Vespera! Lock the dogs!"
Idris fired his dart thrower. Five tungsten needles struck Graven's chest plate in rapid succession, but the pressurized slugs sparked uselessly against the four-inch composite titanium plating.
Graven closed the gap in three seconds.
His hydraulic fist struck Idris in the ribs. The sound of breaking bone was sickeningly loud. The concussive impact lifted Idris off his feet, slamming him backward into the launch railing. His dart thrower slipped from his numb fingers, tumbling into the abyss.
Graven reached down, his massive armored hand clamping around Idris's throat, lifting him until his boots dangled over empty space.
"You have been an irritating nuisance, Calder," Graven rasped through his suit's external speaker, tightening his grip until the cartilage in Idris's neck began to crush. "Your father was a coward who bled out in an abandoned mine shaft. And you are nothing but a scavenger who doesn't understand the machinery he touches."
Idris couldn't breathe. His vision was tunneling into grey darkness.
His right hand twitched, sliding down into his jacket pocket.
His fingers locked around the brass diaphragm—the three-holed disc he had carried from the salt trenches of Threshold Nine through the horrors of the Singing Pit.
Idris didn't strike Graven's armor. He slammed the circular brass disc directly into the acoustic filtration port on the right side of Graven's helmet.
WHISTLE.
The pressurized air circulating through Graven's helmet split across the three apertures. The acoustic frequency of the suit's internal communications loop inverted violently, producing a deafening, twelve-thousand-hertz feedback screech directly inside Graven's ear canal.
Graven screamed—a raw, agonized shriek of ruptured eardrums.
His grip loosened. Idris dropped to the deck, gasping for air as Graven stumbled backward, clutching his helmet with both hands.
Graven was blind with agony, swinging his heavy pile-driver arm wildly in the air.
From inside the pod, Vespera stepped back onto the threshold.
Her eyes were not silver anymore; they were blazing with the pure, incandescent white fire of Lyra's synchronized memory crystal.
She pointed both palms at the catwalk beneath Graven's boots.
CRACK.
She didn't throw an acoustic wave; she dissolved the molecular cohesion of the steel. The catwalk floor beneath Graven's six-hundred-pound exosuit simply ceased to hold. The metal sheared along its crystalline boundaries.
Graven fell.
He plummeted into the roaring heat of the magma lake, but at the last split second, his wrist-mounted magnetic grappling hook fired, embedding itself into the exterior armor plate of the Launch Cradle.
"Idris!" Vespera screamed—a clear, human voice that cut through the thunder.
She grabbed Idris by his collar, dragging him backward into the transit pod's cabin.
With her other hand, she slammed the emergency launch lever.
SNAP-SNAP-SNAP.
The remaining three suspension cables of the Hanging Spire severed all at once.
The entire inverted city of steel and glass detached from the cavern roof, plunging into the molten abyss in a cataclysm of collapsing towers, exploding generators, and geysers of liquid fire.
Inside the Launch Cradle, the magnetic accelerator coils flared.
The tungsten-carbide transit pod was fired down the primary intake conduit at Mach 3, rocketing away from the dying Spire and diving directly into the burning throat of the planetary crust.
The transit pod slammed into the terminal buffer with a bone-jarring impact that crushed the forward crumple zones and threw Idris against the padded restraint harness.
The cabin hissed, venting superheated coolant into the dark.
Idris kicked the emergency release lever. The heavy tungsten door blew outward on pressurized charges, falling flat onto a floor of seamless, polished black obsidian.
He crawled out, clutching his shattered ribs, coughing up a spatter of dark blood.
He looked up, and his breath caught in his throat.
They were inside a colossal spherical chamber, so vast that the far walls were lost in a shimmering haze of blue electromagnetic mist. Floating in the exact geometric center of the void, held in place by six massive anti-gravity rings, was the Core.
It was not a furnace. It was a five-hundred-meter sphere of liquid, translucent crystal that pulsed with a deep, slow rhythm:
Thump... pause... thump.
The Blind Hum was everywhere. But here, at Meridian Zero, it was not the agonizing screech that drove men mad in the salt flats. It was a colossal, harmonic symphony—an ancient, oceanic melody that vibrated in the marrow of Idris's bones, filling him with an overwhelming sense of stillness.
Ahead of them, at the end of an obsidian causeway, stood the primary interface altar: three cylindrical pedestals, perfectly matching the three keys.
Beside Idris, Vespera stepped forward, her silver eyes reflecting the pulsing crystal light.
Then, from the twisted wreckage of the transit pod's launch tube behind them, a heavy metallic footstep rang out against the stone.
Clank.
A shadow emerged from the smoke.
Commander Cassian Graven.
His powered exosuit was scorched black, the left shoulder-plate sheared away, the plasma rifle cradled in his right hand. Through his shattered helmet visor, his face was bathed in blood, but his dark eyes were burning with a terrifying, unyielding madness.
"The girl," Graven whispered, raising the barrel of his rifle. "Is mine."