8th Level Arcane Necromancy (named)
Casting Time: 1 action
Range: 30 sqr. (45m)
Components: V, S, M (a bit of sponge)
Duration: instantaneous
You draw the moisture from every creature in a 6 sqr. (9m) 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.