Chase's Corrosive Acid Geyser (CAG)

A geyser of acid erupts from a point of your choice within range. Each creature in a 40-foot-tall cylinder with a 10-foot radius centered on a point you choose within range must make a Dexterity saving throw. A creature takes 3d6 acid damage on a failed save and their AC drops by 1 until the acid is wiped off with an action (by the creature or ally) or rinsed off with water. The creature that wipes off the acid takes 1d6 acid damage. If the save is failed by 5 or more, the creature takes an additional 1d6 acid damage, and the AC drops by 2 instead. On a successful save the creature only takes half damage. A creature made of inorganic material such as stone, crystal, or metal has disadvantage on this saving throw.

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