The fragment bit, you're reffering to pieces of MX's heart, right? If so, then that doesn't really have relevance. Xigbar explained it himself they were to hook 13 husks to Kingdom Hearts and then divide the heart. That didn't work, because of Ansem's interference. If you're saying that MX already norted everybody but Sora, then how does that make sense when MX was just Reborn???(So to speak) If Saix wasn't norted before this get-together, then Isa wouldn't be effected, saying he's already been Reborn. But, even if so, in this case it's versions that matter, not the mind/whatever. Not to sound silly, but any version will do as long as it's Strong enough, are willing to put their Trust in the cause(Or in Sora's case it didn't really matter), and have a Strong Will to boot.
Another factor I'd like to put on the table is that Numora is leaving us to guess the other 6 Darknesses(For the moment). Therefore, I would say we should have some idea of the other 6. Or 5, if we insist we're still missing a darkness, but even then it should just take some thought-work to figure-out the missing member, like AussyRiku said.(Who knows, it might be the aforemention possible nobody of Master Xehanort)
But here's a new question, even if we don't have a positive answer for the moment, what happened to Terra? Why does only MX get recompleted? Is Terra already saved, and just out there on some world? On that note, if that really is MX? Why of all places is he in Xemnas' chair? What about how Ienzo was going on about how a person should reappear in the place they became a heartless? Or are we to just assume that's where AX became a heartless? And so one question spawns into 5 -_-"
Saix had been norted sometime when he was still a nobody. In both 358/2 Days and KH2 Saix already has the gold eyes and pointy ears which are clear signs of nortification happening. So when Saix was made whole again and became Isa again then surely his reconstructed human form would still be carrying the piece of Xehanort's heart inside of him.
I don't believe every member of the original organization had already been infected with a fragment of MX's heart. But the ones who had golden eyes and pointy ears must have had a fragment in them. This is one reason I think Dilan/Xaldin is one of the Seekers of Darkness, because if you look at Xaldin's ears they are starting to turn pointy.
See I think when different forms of the same person develop a heart, it doesn't normally change who that person is. For example if I become a heartless and a nobody, well the nobody gets the memory and the mind. My nobody isn't a seperate person because it was me who became the nobody. The things in my heart that made me who I was as a human went to the nobody, so the nobody is me.
So for most of the organization they were who they were as humans.
But in the case of Xemnas and Roxas, these two developed their own personality and indentities and thus became their own people. Xemnas ended up this way because his heartless kept it's sense of self, and as such Xemnas didn't inherite the things a nobody normal retains from their heart. Because of this Xemnas developed as his own personality and person. But of course he still wanted to do what MX wanted because his goals are the same as MX.
Roxas' case was different. Sora was a heartless for such a short time that Roxas didn't have time to recieve the things a nobody normally recieves from their heart. As such Roxas eventually becomes his own person. We see this clearly in 358/2 Days. He starts out like as Axel says "A Zombie" but we see him gain his own personality as the game progresses.
So those two along with Namine are the exceptions to the rule. For most of the organization they are not seperate personalities from their time as humans, but simply the same person they were as humans, but they just became nobodies.
What I was thinking about when you add a fragment of MX's heart into the equation, is that as that fragment grows and become more and more of the person's heart then it causes the person to become a hybrid personality. They would begin to think, act, and look more and more like MX while keeping traces of their own personality. Once MX's heart fragment completely takes over a heart, the person becomes Xehanort himself. Not a clone or a replica, but an exact new Xehanort coexisting with the original Xehanort who is MX. It is difficult to explain.
Why do I suddenly imagine Xehanort lying in a cradle with a baby's rattle uttering his very first words. *ggg*
"Da-da-da...X-blade." lol.
Can you imagine what it must have been like for MX's parents to have to raise him? If they could only see him now, all grown up and screwing the worlds up.
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