Arcing Current

You send a bolt of electricity that arcs towards single target. If it hits it can arc to other enemies. Make a ranged spell attack against a creature in range. On a hit, the target takes 1d6 lightning damage. You may then deal an additional 1d6 damage to either the original target, or to a creature within 10 feet of the target that must then make a dexterity saving throw to avoid the damage.

The additional damage increases by 1d6 when you reach 5th level (2d6), 11th level (3d6) and 17th level (4d6). This damage may be spread between creatures in range, hitting up to 5 creatures at 17th level. However, no matter how the additional dice are distributed, no creature can suffer more d6's than the original target.