ff worlds in kingdom hearts would be...dull...cropped, and short. final fantasy worlds, even stories aren't something you can squeeze all in one world. considering that, it would be close to impossible to fit a full sized game within the kingdom hearts 3. they would have to crop the story or cut it short. final fantasy stories are long, elaborate, and detailed. you can't just zoom through it like a disney movie. you could beat mulan in 20 minutes and go through the whole story just like that. but no, if they put an ff world in kingdom hearts 3 they would hardly do it justice. it just doesn't make sense to show one world, like midgar for example...and just make you play a snippet of the elegant plotline. then again, there wouldn't be enough room to fit in the entire final fantasy story for any of the games worth sharing...as i previously stated, they are long and elaborate. final fantasy worlds deserve more than to be crammed in their little space in some other square-enix game. that's the sort of thing you do with things that are collapsable and cropable, like disney movies.