Blinding Ash

You create a cloud of thick ash in a 30-foot radius sphere around a point you can see. The cloud spreads around corners, and its area is heavily obscured. Fire spells do not burn off the mist, but water- and cold-based 23 Book of Lost Spells spells do dispel the magic. Each creature in the cloud takes 2d6 fire damage at the beginning of its turn. The cloud lasts for the duration of the spell or until a win