Acid Blast

A blast of caustic acid erupts from your fingers. Every creature in a 30-foot cone must make a Dexterity saving throw, taking 6d8 Acid damage on a failed save, or half as much damage on a successful one. A creature that fails its saving throw also takes an extra 2d8 Acid damage at the end of its next turn. 
At Higher Levels: If you cast this spell using a spell slot of 5th level or higher, the damage (both initial and later) increases by 1d8 for each slot level above 4th.