BloodFall

A dark red cloud appears in a location you choose within range. The area of the storm consists of up to ten 10-foot cubes, which you can arrange as you wish. Each cube must have at least one face adjacent to the face of another cube. Each creature in the area must make a Dexterity saving throw. It takes 2D12 piercing damage on a failed save, or half as much damage on a successful one.

The blood taints anything caught in the storm in a thick red. All plant life dies.