Apparently what we know as Final Fantasy IV was originally going to be Final Fantasy V for the super famicon. the above picture is a mock up of what Final Fantasy IV for the nes would most likely have looked like in the beta stages had it gotten past the drawing board. So yes, there is a lost final fantasy game, but only in concept because it never made it past a concept sheet and into a playable beta.
For more infos: www.lostlevels.org/200311/200311-square.shtml
U64 is an archive with articles, screens and videos for cancelled, beta & unseen videogames. Every change & cut creates a different gaming experience: we would like to save some documents about this evolution for curiosity, historic and artistic preservation.