A cone of lightning 10 feet long and 15 feet wide blasts out from your hand(s) in a direction you choose. Each creature in the cone must make a Dexterity saving throw. A creature takes 1d12 lightning damage and is now prone on a failed save, half as much damage 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 2nd level or higher, the damage increases by 1d12 for each slot level above 1st.