Use the right arrow to move right, left arrow to move left, up to jump, and to mega punch use the big ol space bar. If the OOF in the corner says 15 or more on it, you have been squashed by KING SCUTTLEBUG. Also, zap scuttlebug is a one shot, so be careful. One last thing, the goal is to get the king scuttlebug hp bar up to 30. Have fun :)
This isn't really mario-ish, but I am mediocre at best at coding, so this is what I have to work with.