Deep beneath the earth, where the darkness is so dark it's almost palpable, the dragons of the Underworld gather to bask in the radiant glow of the Iron Storm. This cataclysmic event is not just a natural occurrence, but a carefully crafted ritual performed by the dragon elders to imbue their kin with the essence of the land.
When the stars align just right, and the winds howl through the caverns, the Iron Storm is said to occur. No one truly knows the frequency, but it's said to be once every thousand years.