Blue Flame

You point a blue torch like fueled line of fire at a creature or object within range. Make a ranged spell attack against the target. On a hit, the target takes 10d6 fire damage. A flammable object hit by this spell ignites if it isn't being worn or carried. Roll your Intelligence (DC16) continue your concentration or lose it when you pick another creature or object in range. Metals begin melting after 5 rounds. Completely molten after 10 rounds.

This spell's damage increases by 1d6 when you reach 6th level (2d6), 12th level (3d6), and 18th (4d6) .