When I was little, an older kid told me that the devil was in the physical form just like us, but he was invisible. So basically he walked around the earth doing evil and got away with it because no one could see him. So my idea was to randomly shoot a cannon around in order to kill the devil. I wondered, "Why hasn't anyone thought of this before?" We would get rid of the devil by chance. He'd get hit, and we'd know he died because suddenly all evil in the world would cease. That and there would probably be a thud. Maybe some blood and a bit of drama or maybe something like what happens when you beat a video game. I didn't have the ending figured out, but at least I knew how to get the job done.