Blightning

A stroke of black lightning forming a line 100 feet long and 5 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 4d6 lightning damage on a failed save, or half as much damage on a successful one. However targets that do fail their constitution save, can't use magic for 1d4 rounds.

The black lightning snuff out any non-magical fires in its path.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d6 for each slot level above 3rd.