Elemental Bomb

Elemental energy manifests at a point you choose within range and then blossoms with a low roar into an explosion. Each creature in a 20-foot-radius sphere centered on that point must make a Dexterity saving throw. On a failed save creatures take 8d6 damage of your choosing from acid, cold, fire, or lightning (or any mixture of the four), or half as much damage on a successful one.

The element used spreads around corners. Each energy type affects objects in the area that aren't being worn or carried differently. An example would be fire ignites objects.

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.