Voltaic Clouds

You create 4 floating storm clouds each size large within range that lasts for the duration. When you cast the spell, 3 bolts of lightning shoot out in a 5-feet line from a cloud's space to another. The bolts do not need to originate from the same cloud. Each creature in a line must make a Dexterity saving throw. A creature takes 6d8 lightning damage on a failed save, or half as much damage on a successful one.

The space within a cloud is considered heavily obscured and is included in the area of effect of the lighting.

As a bonus action on your turn, you can move the clouds up to 20 feet and shoot 3 more bolts of lighting.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, one additional bolt leaps from a cloud to another for each slot level above 6th.