I came up with this big brain idea. What if I played all the mainline Mario games, but every time I get a coin, I switch on to a new game. I'll call it "Coin%". Is anyone up to make it an official category?

It would be like 45 mins but yeah

And what's the goal of that category? Is it getting the coin as fast as possible to get to next game, thus trying to finish all games as fast as possible?

yes

Do a run of it

I know I'm late to this but heck yeah this would be a good category