Heavy iron drill-heads ground against the basalt fault lines, sending sharp vibrations screaming down the western lava tube.
General Dravus was done with stealth.
After losing two bronze resonance drums and twelve shadow-censors, the imperial warlord had mobilized his elite combat engineering battalions.
Two thousand iron-armored sappers had entered the subterranean tunnels, hauling heavy pneumatic steam drills, spiked pavises, and barrels of suffocating sulfur-pitch.
Their orders were brutal: carve through the basalt choke point, breach the underground lake, and collapse the roof upon the rebels.
At the narrowest point of the lava tube, the stone corridor pinched down to barely six feet in width.
Sera Thorne stood at the center of the bottleneck.
Her ancestral weapon, Storm-Pike, hummed with fierce, violet lightning.
