Arc Lightning (Revised)

You create a bolt of lightning that arcs toward a target of your choice that you can see within range. The target must make a Dexterity saving throw. The creature takes 2d8 lightning damage on a failed save, or half as much on a successful one.

Lightning arcs from the creature, and you are able to target up to 2 additional creatures within 20 feet. Those creatures must make Dexterity saving throws. Each target takes 1d8 lightning damage on a failed save, or half as much on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage (both initial and arcs) increases by 1d8.