I recommend first getting the achievement for playing on each level in versus. That will net you at a minimum 39 plays in versus mode. For the remaining ones I found it fastest to set the computer up to 5 star difficulty and then just load the first level. Don't move and just let the computer kill you and then afterwards just hit "Retry". It takes about 8-10 seconds for each play. Following that method you will have it pop in no time!