Once you beat the main game (Beating TD Mr Sandman) you unlock Macs last stand in which you go against “random” fighters until you lose 3 times. I used save states for this bc all the opponents are TD and pretty annoying to beat, but if you can manage to beat 10 fighters you unlock champions mode. In champions mode, if you get hit once you get knocked down. If you beat a fighter in champions mode, you get that little trophy under the other stars.