The ancient floor plates of the Sub-Level 8 command dome vibrated with a deep, sickening pulse.
It wasn't the rhythmic thrum of the Abyss Engine, nor was it the shifting of the deep salt strata.
It was the shockwave of heavy orbital displacement from three miles above.
"They're here," Maya said, her eyes fixed on the flickering tactical console of the acoustic relay.
[WARNING: ATMOSPHERIC PENETRATION DETECTED IN PRIMARY VENTILATION SHAFT]
[OBJECT COUNT: 12 HEAVY DISPLACEMENT PODS]
[PROJECTED IMPACT ZONE: SECTOR 4 CENTRAL PLAZA]
[ESTIMATED TIME TO IMPACT: 180 SECONDS]
Up in Sector 4's central plaza, the warm air was suddenly shattered by the scream of tearing iron.
Massive blast doors at the top of the main shaft—sealed for over forty years—were sheared open by thermal charges.
A cluster of heavy steel drop-pods, painted matte black and bearing the silver sigil of the High Directorate Vanguard, plummeted through the shaft.
They cut through the rising steam like iron meteors.
Inside the tactical bunker near the North Gate, Master Oakes watched the seismic gauges jump off the scale.
"Miners! Clear the central concourse!" Oakes roared into his radio transceiver, his raspy voice cracking with urgency.
"Fall back behind the secondary salt-barricades!"
"Do not engage the pods on impact!"
BOOM! BOOM! BOOM!
The drop-pods smashed into the iron floor of the central plaza, crushing empty market stalls and driving deep craters into the stone floor.
Braking thrusters fired at the last second, filling the cavernous plaza with blinding white light and toxic hypergolic fumes.
HYDRAULIC HISS.
The armored hatches of the pods blew outward simultaneously, crashing to the ground with heavy thuds.
Out stepped the Vanguard Purge Troopers.
They were clad in bulky, open-cycle exoskeleton suits, their faceplates completely sealed behind dark, polarized visors.
Each trooper carried a heavy, water-cooled rotary auto-cannon or a high-frequency thermite lance.
"Perimeter clear," a digitized voice boomed from the lead pod, echoing harshly through the plaza's loudspeakers.
"Target area: Sector 4."
"Civilian status: Non-compliant / Tech-Heresy suspects."
"Primary objective: Secure Node 06 power feed and eliminate the unauthorized Mark carrier."
"Secondary objective: Purge local population."
The lead Vanguard Commander raised his heavy gauntlet, signaling his squad to advance toward the residential quarters.
"Begin the sweep."
Down in the Secondary Acoustic Control Core, Danial stood with his bare left hand pressed against the glowing central sphere.
The Gold Mark burned like liquid fire across his skin, weaving his consciousness directly into the subterranean acoustic array.
[SENSORY LINK ESTABLISHED: SECTOR 4 SUB-SURFACE ARRAY]
[VANGUARD UNITS DETECTED: 48 ARMORED TROOPERS, 2 HEAVY EXOSUITS]
[ACOUSTIC DAMPENING NETWORK: 100% OPERATIONAL]
[SELAR SENTINEL UNIT: AWAITING FREQUENCY COMMAND]
"They're moving toward the residential sectors," Maya reported, her hands flying across the auxiliary controls to feed Danial real-time telemetry.
"Oakes' barricades will buy ten minutes, but those rotary cannons will shred the barricades to pieces."
"They won't get past the North Gate concourse," Danial said softly.
His eyes, reflecting the bright golden light of the core, narrowed as he isolated the internal communications frequency of the Vanguard suit arrays.
"Maya, set the secondary dampener node to 14.2 kilohertz."
"Targeting the main ventilation shaft and the lower salt conduits."
Maya paused, her fingers hovering over the bronze dial. "If we broadcast that frequency unshielded, every dormant Selar construct within three miles will wake up."
"That's the point," Danial replied.
"The Vanguard came down here thinking they were fighting starving miners with pipe-rifles."
"Let's remind them why the surface cartels never dared to explore Sub-Level 8."
Maya locked her jaw and drove the primary bronze lever forward into the activation notch.
HUMMMMMMMMM!
The massive obsidian sphere suspended over the chasm flared with golden light.
A invisible wave of focused acoustic energy shot upward through the salt strata, traveling along the ancient terraforming pipes at the speed of sound.
In the central plaza, the Vanguard Commander suddenly froze in mid-stride.
Inside his armored helmet, his audio sensors exploded with static.
"Command, this is Vanguard Alpha," the Commander barked, touching his helmet interface. "We are experiencing severe acoustic interference."
"Scramblers are failing."
"All units, lock your internal dampeners—"
Before he could finish his command, the ground beneath the central plaza began to groan.
CREAK... CRACK!
The salt-crusted floor plates around the drop-pods buckled outward.
From the dark, unmapped drainage vents beneath the plaza, dozens of pristine, chrome-armored Selar constructs began to emerge.
Their optical sensors burned with the same deep gold light that radiated from Danial's mark.
They moved with terrifying, fluid speed, leaping over the rubble without making a sound.
"Hostiles!" a Vanguard trooper yelled, swinging his rotary auto-cannon toward the vents. "Selar constructs! Open fire!"
RAT-TAT-TAT-TAT-TAT!
Muzzle flashes illuminated the hazy plaza as heavy armor-piercing rounds tore into the salt fog.
The bullets struck the Selar units' chrome plating, ricocheting uselessly off their polarized kinetic shields.
The Selar units did not attack blindly.
Guided by the precise acoustic routing from Danial's core relay, they ignored the scattered civilians fleeing into the side tunnels and converged exclusively on the Vanguard squad.
A pristine Selar Sentinel lunged forward, its multi-barreled acoustic lance discharging a high-frequency sonic blast directly into the lead exosuit.
BOOM!
The heavy armor of the Vanguard suit buckled inward under the pure pressure wave, its hydraulic lines rupturing and spraying steaming fluid across the salt floor.
"Fall back to the pods!" the Vanguard Commander shouted, firing his thermite lance to create a wall of fire between his men and the constructs.
"Their shields aren't degrading!"
"What is driving these things?!"
Deep below, Danial watched the battle unfold on his translucent system map.
[ENGAGEMENT STATUS: VANGUARD ADVANCE HALTED]
[SELAR CONSTRUCT EFFICIENCY: 94%]
[SECTOR 4 CASUALTIES: 0]
[WARNING: HEAVY DREADNOUGHT SIGNATURE DETECTED AT TOP OF SHAFT]
Danial's breath hitched as a massive new icon appeared at the top of his HUD.
A Class-4 Vanguard Dreadnought—a four-legged, heavily armored combat platform equipped with siege mortars—was preparing to descend the shaft to reinforce the Purge Troopers.
"They're dropping the heavy armor," Danial said, his voice cold as he adjusted his grip on the control core.
"Maya, seal the primary lift gates."
"We're bringing the entire Vanguard landing force down into the salt vaults."
Maya looked at him, a fierce smile touching her lips as she pulled the secondary override switch.
"Sector 4 is closed for surface business."