A few years back I made a few flashes about Magus getting training from Mario as a tribute to Captain SNES. Always said I'd make a third one and the 10th anniversary of CSNES was a few days ago so I decided to actually finish this after sitting on it for so long. I honestly doubt anyone who watched the older ones back then is even on NG any more, but here you go. I also added a couple of extra flashes in there because I felt like it.
Braveshroom is a goomba in the comic that Mario paid off to teach Magus about jumping on enemies' heads. Said goomba let his victory over Magus go to his head and decide he was the chosen hero of goombas. And it kind of snowballed from there.