8th-level necromancy

Casting Time: 1 action

Range: 150 feet

Components: V, S, M (a bit of sponge)

Duration: Instantaneous

You draw the moisture from every creature in a 30-foot cube centered on a point you choose within range. Each creature in that area must make a Constitution saving throw. Constructs and undead aren’t affected, and plants and water elementals make this saving throw with disadvantage. A creature takes 12d8 necrotic damage on a failed save, or half as much damage on a successful one.

Nonmagical plants in the area that aren't creatures, such as trees and shrubs, wither and die instantly.