Cloud of Pestilence

You create a heavily obscured 15-foot radius sphere of green fog centered on a point you can see within range. The fog spreads around corners but is stationary and lasts the duration unless dispersed by a strong wind (at least 20 miles per hour), which ends the spell after 1 round. When a creature first enters the cloud or starts its turn there, that creature must make a Constitution saving throw or take 4d6 poison damage or half as much on a successful save. Creatures are affected even if they hold their breath or don’t need to breathe.

At Higher Levels. When you cast this spell using a spell slot of 5th or higher level, the poison damage increases by 1d6 and the radius increases by 5 feet for each slot level above 4th.