Controversial opinion time: being able to deal with a lot of different scenarios, stages, and battle conditions makes you more ‘elite’ than someone who can beat anybody else as Fox only, no items, Final Destination. I won’t be playing much online, mind, so I can say that without fear of much consequence.
You know who’s really elite? The person who did that Smash Bros./Rhythm Paradise mash-up above. They’ve done a Sumo Bros./Manzai Birds one too (it’s in the mentions for the other one).
Three days...