Bolt of the lightning god level 1

You borrow some of the powers of the lightning god and form lightning that is 150-foot-long, 5-foot-wide Line blasts out from you in a direction you choose. Each creature in the Line makes a Dexterity and a Constitution saving throw, taking 12d8 Lightning damage on a failed save or half as much damage on a successful one.

Using a Higher-Level Spell Slot. The damage increases by 2d8 for each spell slot level above4.