You can actually make a beat 'm' up within 24 hours

Take a look at Uber Fighter: http://necrodome.homeftp.net/Project...roject=Game_24

The way we did it was by making an animation from about 5 frames and in each frame a hot spot to identify if there was a hit. If frame has no hot spot, there can't be a hit (or kick). We also have combo moves, but they didn't make it within 24 hours...

Second you need a very simple 2D scrolling background...

Put it together and you have your fighting game.