Tesla Beam

A stroke of lightning forming a line 85 feet long and 15 feet wide blasts out from you in a direction you choose. Each creature in the line must make a Constitution saving throw. A creature takes 3d12 lightning damage on a failed save, or a third as much damage on a successful one.

The lightning ignites flammable objects in the area that aren't being worn or carried and can activate anything requiring electricity. 

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d8 for each slot level above 5th.