>>33798021Honestly? Quite a lot. There are plenty of games that are less than a gig, even less than half a gig, that are surprisingly big. Your biggest files are sounds and textures, and let's face it; pokemon is not graphically intense. You'd only need a few new overworld tracks for ultra space, because each ultra world for the UB's will most likely share their theme, and one for Ultra Megalopolis, as well as a theme for Necrozma. There will be more, but not many.
To really demonstrate how much file size actually comes from sounds and textures, here is a game that is less than 100Kb.
https://www.youtube.com/watch?v=2NBG-sKFaB0It looks barebones as fuck of course, but you have to remember, this isn't even a tenth of a megabyte. Now, I know GF isn't going to be anywhere NEAR this good at managing their files to get the most out of the least, there's going to be clutter. Of course there is going to be clutter. But I think the thing we'd really need to know is how much of the 3.2 gigs of SM was taken up by the Pokemon themselves, and how much was taken up by the music. You separate those numbers from the total and you'll get a rough estimate of how much space there really is in Ultra Space in USUM.