This is an implementation of the Zap spell from Tasha's Crucible of Everything Else

A stroke of electricity forming a line 20 feet long and 5 feet wide blasts out from you in a direction you choose. Each creature in the line must succeed on a Dexterity saving throw or take 1d6 lightning damage. The electricity ignites flammable objects in the area that aren’t being worn or carried.

This spell’s damage increases by 1d6 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).