Boom Boom
Boom Boom is a boss that Mario fights in each fortress in Super Mario Bros. 3. He is very easy to defeat - all Mario had to do was jump on his head three times, or hit him with fireballs or hammers, if he posessed the Fire Mario and Hammer Mario power ups. Many fans argue that the fortress obstacles themselves were harder than the Boom-Boom fight. Boom Boom would begin by simply walking left and right towards Mario. After being hit, he would start to charge, jump, and fly. It is unknown if there is only one Boom Boom, or if there are multiple Boom Booms which would make Boom Boom a species rather than a villain.
Boom Boom appeared in Mario cartoon series The Adventures of Super Mario Bros. 3, where he was a dim-witted power house.
In the Mario Bros. Movie, there was a bar called "Boom Boom Bar" and one of the background people could be Boom Boom.