User blog comment:Plasmaster/Smash 5's Stage Roster/@comment-25275196-20160418231521/@comment-6684591-20160424053810

I feel like Prison Island (or Imperial City Alcamoth) would be a travelling sort of stage but instead of a platform carrying fighters between locations, it would utilize the High Entia Teleporter technology. This shows how I think the stage will work:

http://supersmashbrosfanon.wikia.com/wiki/SSBR%3A_Imperial_City_Alcamoth