Tesla ball

A bright streak flashes from your pointing finger to a point you choose within range and then blossoms with a low crackling an explosion of lightning. Each creature in a 20-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 8d6 lightning damage on a failed save, or half as much damage on a successful one. In addition, on a failed save. The target takes an additional 1d6 thunder damage and gets knocked back 10 feet and stuned until the end of your next turn.

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.