Electric blast

A magic circle appears in front of your outstretched fingers as you speak the incantations. A bright streak of energy bursts from your hand to a point you choose within range and then explodes with a thunderous crack into an explosion of electricity.. Each creature in a 20-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 8d6 electric damage on a failed save, or half as much damage on a successful one.

The lightning spreads around corners. The spell does double damage to any metal structures, people or items. 

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.