Chained Bolt

A bolt of lightning erupt from the casters fingers that when hit and enemy can split and attack other enemy(s) dealing 2D6 lightning damage

the target when hit roll a constitution saving throw if save fail then the bolt splits off and attack a second enemy, this effect can happen up to 4 times maximum 

when cast at higher levels add a D6 and one extra max number of target by one per spell slot level above 2