Volcanic Ash

You create a 20-foot-radius spherical plume of blackened, noxious gas centered on a point within range. The plume spreads around corners, heavily obscured the area. The ash plume lingers in the air for the duration.

Each creature that is completely within the plume at the start of its turn must make a Constitution saving throw against poison. On a failed save, the creature spends its action that turn coughing and gasping. Creatures that don't need to breathe or are immune to poison automatically succeed on this saving throw to withstand the noxious gases.

A moderate wind (~10 mph) disperses the volcanic plume after 4 rounds. A strong wind (~20mpg) disperses it after 1 round.