Arcing Blast

You target a creature in range that you can see and make a ranged spell attack. If the attack hits the creature takes 3d6 lightning damage and then the target becomes sheathed in electricity. At the beginning of the creature's next turn it needs to make Constitution saving throw taking a 1d6 lightning damage on a failed save, and the effect spreads to two additional creatures of your choice within 50 ft. of the original creature (no action). Those creatures will also need to make a saving throw during each of their turns. A creature is affected by this spell until the spell ends or until they succeed a saving throw.