Thunder Ray

Crackling bolts of lightning spray towards a point you can see within range. When the beam hits a non-living object it didn't kill, or the end of it's range, the beam explodes into a 30ft radius sphere. The sphere spreads around corners. Each creature in the path of the beam (15ft diameter) must make a Constitution saving throw. Each creature in the sphere must make a dexterity saving throw. Each creature must take 4d10 thunder damage on a failed save or half as much on a succesful one.

The spell damages objects in the area of the sphere and ignites flammable objects that aren't being worn or carried. Anyone hit by both the beam and the sphere must make both saves and take damage from both. Creatures hit by both are stunned until the end of their next turn.