Crap, I totally meant Ansem - I get them confused all the time! I've already beaten Xemnas, and dropped back over to Riku. Thanks for that tip!You can pick up Dark Splicer in the final world which absolutely kills all final bosses on Riku's side. Not sure about Sora, though -- I didn't use any commands on Xemnas.
The World That Never Was *is* the final world. From the room with the pillar in the center that was shooting lasers at you, there's an easily missed path to a new area with a wall that has a bunch of blocks moving in and out of it. You need to make your way to the top and the chest will be there.Crap, I totally meant Ansem - I get them confused all the time! I've already beaten Xemnas, and dropped back over to Riku. Thanks for that tip!
Edit: I can't get Dark Splicer yet, I'm still in The World That Never Was. Any other suggestions?