The Breath of the Stone-Father

The back of the cavern opens into a circular vault where four concentric copper rings are mounted into the stone wall. A howling wind rushes out from a central blowhole, catching the internal vanes and causing the heavy metal rings to spin at dizzying speeds. Each ring is etched with various primal symbols that blur into copper streaks as they rotate. A faint hum of abjuration magic vibrates in the floor, and the air smells sharply of ozone and old, dry dust.