For twenty days, I survived on cave moss and the condensed droplets of shadow ether dripping from stalactites.

Using volcanic slate and carved basalt crystals, I constructed a rudimentary reverberatory furnace. The black quicksilver was unlike any metal known to the surface empire; it had zero electrical resistance and absorbed pure magical radiation without boiling.

When I channeled my exhausted life mana into the crucible, the shadow mercury crystallized into a ring of obsidian glass that hummed with gravitational pull.

"Transmutation complete: Void Glass Catalyst," I whispered. My right hand, corrupted by frostbite, regenerated in seconds beneath the ring's soothing dark luminescence.