Elemental Dragon Exhalation

You gather elemental power in your lungs, selecting one damage type out of acid, cold, fire, lightning, or poison, and then exhale it in a mighty gust of energy. Each creature in a 20-foot cone must make a Dexterity saving throw. On a failed save, a creature takes 3d8 damage of the chosen type, or half as much damage on a successful save. If you cannot breathe, have no mouth, or your mouth is currently covered, the spell fails.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d8 for each level above 2nd.

Source Book: Kibbles Compendium of Legends and Legacies