Cloud of Death

You create a 20-foot-radius Sphere of misty, purple and black fog centered on a point you choose within range. The fog spreads around corners and into the Ethereal Plane. It lasts for the Duration or until strong wind or a Daylight spell disperses it. Its area is heavily obscured.

When a creature enters the spell's area for the first time on a turn or starts its turn there, that creature must make a Constitution saving throw. The creature takes 15d8 necrotic damage on a failed save, or half as much damage on a successful one. Creatures are affected if they have any exposed skin.

The cloud moves 10 feet directly away from you in a direction that you choose at the start of each of your turns.

At Higher Levels: When you cast this spell using a 9th level spell slot, the creature takes an additional 5d8 necrotic damage, as well as must make a Wisdom saving throw. On a failed Wisdom save, the creature takes a point of Exhaustion.