Why would it be based off Final Fantasy XIII? Other than Dalamud and the Weapons being related to VII and the Warring Triad legion being related to VI, the other ones really don't have anything to do with their games. Heck, Gabranth's legion is not even XII, it's IV!

Speaking of, Final Fantasy XIII has to be the game with the least amount of references in this game... The only thing I can think of is the Twinning dungeon.