Before I begin, I would like to apologize if this is already obvious and I'm just really slow on the uptake. Also, spoilers ahead.

 

 

 

 

 

 

 

When I was playing Dream Drop Distance and I got the the part where Master Xehanort makes his grand return, I was under the impression that he was time displaced like all of his other selves because he looked old instead of still having Terra's body but after I did some digging I've realized that I may be wrong. During Kingdom Hearts 1, Ansem took over Riku's body and and after a while turned it into his own. In Chain Of Memories and 358/2 Days, Riku transforms into Ansem whenever he taps into his inner Darkness. Kingdom Hearts 2 has Roxas looking nothing like Sora but looking everything like Ventus and regular Nobodies are just formless and malleable silver blobs.

 

Here's where I'm going with this: bodies in Kingdom Hearts are all formless blobs and it's the Heart inside of it that gives it any distinctive physical shape as shown by all of the examples above which is where Xehanort comes in. In Birth By Sleep, Xehanort possesses Terra and this changes Terra's eyes yellow, his hair silver, and makes his skin a darker color but it isn't a full conversion because Terra's Heart was still in there fighting for control. Now that Xehanort has reformed, he looks like his elderly self again but that doesn't mean his body is old, that's still Terra's body but Xehanort's heart is in full control now.

 

This also adds to the secondary title of this theory: Nobodies are not only called that because they lack a Heart and technically don't exist, but because they're all completely faceless and formless and are now completely indistinguishable from themselves. They are Nobodies in every sense of the word.

That's actually some pretty deep stuff when you think about it, man! And quite sad!  Since all of them are just formless beings!

 

And also, that bit with Xehanort seems interesting!  The heart shapes the vessel, they say, and this could very well be what happened to Terra's body! It's still there, but as you said, Xehanort is in full control, and by other people's eyes, Terra's body looks like Xehanort's!

However, the DDD Ultimania explicitly calls MX's revived form his "true body" -- i.e., the original from BBS.

However, the DDD Ultimania explicitly calls MX's revived form his "true body" -- i.e., the original from BBS.

If that's the case then what was the point of possessing Terra? That's one of the things I hate about this series, nothing ever gets properly explained in the games and the books that do explain them are Japan exclusive and even then there's only vague explanations. I'm starting to agree with a bunch of other people, Nomura is a complete and total hack of a writer.

Ya know, I think you're onto something. Now if only we could be able to FINALLY get some answers from 2.8, that would be great