Blunderbuss Blast

You brandish the weapon or piece of ammunition used in the spell’s casting, imbuing it with condensed fire magic, and make a ranged attack with it or an appropriate weapon against one creature within range. On a hit, the target suffers the weapon attack’s normal effects, and you can then cause an adjacent creature, a non-worn or carried item, a structure, or a 5ft square of floor that isn't directly behind the target to take fire damage equal to your spellcasting modifier. Targeted ground becomes difficult terrain if it's not immune to fire damage.

The number of non-creatures this spell can target after a successful hit, as well as damage, increases when you reach certain levels. At 5th level, the ranged attack deals an extra 1d8 fire damage to the target on a hit, and you may target one additional structure or 5ft square of floor, and the fire damage to structures or objects increases to 1d8 + your spellcasting ability modifier. Both damage rolls increase by 1d8 at 11th level (2d8 and 2d8; two extra targets) and 17th level (3d8 and 3d8; three extra targets).