Death Lightning

You create a bolt of lightning that arcs toward a target of your choice that you can see within range. Three bolts then leap from that target to as many as three other targets, each of which must be within 30 feet of the first target. A target can be a creature or an object and can be targeted by only one of the bolts.

A bolt of lightning leaps from your fingertips towards a point you know exists. Any structure or creatures within a 60-foot cube (centred on the point) is targeted by this spell. You need to have seen the point and must make a history (dc 15) check to make sure

 The targets take 100d100 lightning damage on a failed save, or half as much damage on a successful one.