Black Lightning Bolt

A stroke of black lightning forming a line 150feet 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 6d8 lightning and necrotic damage and also becomes paralyzed on a failed save, or half as much damage and doesn't become paralyzed on a successful one.

The lightning ignites flammable objects in the area that aren't being worn or carried.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the damage increases by 2d4 for each slot level above 5th.