basically: wizards has been making sets based on third party licenses (a controversial move) and sometimes for legal reasons they're only allowed to print those sets on paper and not put them into mtg arena. but that would fuck with balance so now they're making functionally identical versions of those sets but with different card names and art just for arena
@codl I don't generally follow MtG either so I'm just now hearing about this, and, looking into it, I'm somehow surprised Final Fantasy wasn't a factor in this move