The massive iron blast doors groaned under the force of Sagiri's Silver-Veined Void Blades, buckling inward before collapsing onto the freezing stone floor with a thunderous crash.
A blast of stale, frigid air rushed out of the mountain's dark mouth, thick with the sharp stench of alchemical exhaust, sulfur, and burning coal.
Sagiri stepped over the twisted iron threshold, his dual-colored eyes piercing through the heavy gloom of the subterranean labyrinth.
Ahead stretched a colossal underground cavern carved from black granite and ancient glacial ice, illuminated only by the sickly blue glow of alchemical braziers.
Massive iron catwalks spanned across yawning chasms, suspended above deep mining pits where steam-powered drills shrieked against the stone.
Down in the frozen pits, thousands of emaciated prisoners men and women from all five lands labored in heavy iron chains, hauling glowing ore carts under the whips of brutal overseers.
