Uni-the-Unicorn!
Hero
Anything that TSR owned when WotC bought them (which is the vast majority), anything that WotC added (Eberron & Nentir Vale), and all MtG settings. Though if the premise these are different companies now, that last one could be in limbo.I have no knowledge about what settings they own trademarks and copyrights for. I assume that they don't have all of them. If they're separated from WotC, they probably can't do anything with MTG settings. I suspect extensive legal research would have to be done on a lot of them.