Posted by MolineTrust me, I am going to research super mario galaxy hacking.
so, first. having ideas leads nowhere if you don't think them up while respecting two major terms:
one, it's doable. noone will join something that isn't even possible, so you have to adjust to thinking within the boundaries of the possible before to dice out any ideas.
in other words, learn first, experiment what you can do, and only then proceed.
two, it's something people would want. extra galaxies added to the game, requiring a completely altered save data? with "harder extra challenge levels" the game already has?
you'd have to replay all the levels, annoying challenges and everything just to access those new levels. honestly, fuck that.
you'd be better off recreating the current levels.