Elements' Veil

You summon a swirling mass of elements in a 15ft radius, 40ft tall cylinder centered on a point you see within range. Each creature that begins their turn in the veil or moves into it during their turn must make a Dexterity save. A creature takes 3d6 damage from an element of your choice, (cold, fire, lightning, or thunder) on a failed save, or half as much on a success, which expends that type from the veil.

The spell ends once all four damage types are expended, or the spell ends for another reason.

At Higher Level. When you cast this spell using a slot of 3rd or higher, the damage increases by 1d6 for each slot above 2nd.