Tesla Coil

A bolt of lightning energy extends from the metal rod to a random enemy within the range of the spell. Count and number every creature within the radius around you (not including yourself). Roll a dX depending on how many enemies are around you. Whatever number you roll, the corresponding creature must a Dexterity Saving throw, taking 5d10 lightning damage on a failed save, or half as much on a success. On each subsequent turn, you may use your action to have another bolt of lightning extend from the rod.