Dragon's fire

A spiral of fire issue out form the casters hand and burns all in it paths that are caught in a 20-foot-long and 10-foot-wide cone and must make a Dexterity saving throw. A target takes 6d6 fire damage on a failed save, or half as much damage on a successful one.

It 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 1d6 for each slot level above 1st.