Electric Bolt

You hurl a lighting bolt at a creature or object within range. Make a ranged spell attack against the target. On a hit, the target takes 1d10 electical damage and is stunned for one round.

This spell's damage can jump to another creature with in 10 feet of the first when you reach 5th level, 11th level two more creatures so total of four, and 17th level 2 more creatures so a total of 6 creature all with in 10 feet of each other.  Each creature affected in this way uses the initial attack roll to determine if it is affected by the spell against thier AC.  If any creature AC is greater or is immune to electrical  damage the spell ends with that creature.