Corrosive Ruin (HB)

A conjured wave of acid sprays out from your hand, coating the area. Each creature in a 15-foot cube originating from you must make a Dexterity saving throw. On a failed save, a creature takes 5d6 damage and is coated in acid, taking 2d6 acid damage at the start of its turn until an action is used to remove the acid. On a successful save, the creature takes half as much damage and isn't covered in acid.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the initial damage increases by 2d6 for each slot level above 3rd.