Brody's Big Ball Barrage of Blasting

A twisting glob erupts from your fingers to a point you choose within range, then flashes into an explosion of elemental power. Each creature in a 20-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 6d6 elemental damage on a failed save, or half as much damage on a successful one. You choose what the damage type is before you cast the spell.

You may choose fire, cold, acid, lightning, poison, thunder, or force damage. Alternatively, you may choose to assign an elemental damage type to each d6 instead of all of them. 

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.