True; that is a possibility and what I was pretty sure happened before this revelation. Master Xehanort did come back in his own body, though, so it all depends on whether it was Terra or Aqua he was referring to.
Also true; although saying that Ventus might be Norted was more poor wording on my part. The idea of Ventus being able to spy on Xehanort through his empty body should the worst-case scenario come to pass is an interesting one I hadn't thought about... To be perfectly honest, I'd rather Ventus's empty body not get possessed by a shard of Xehanort's heart, but if Aqua is a Seeker of Darkness, that is a real possibility. I said that it would be ironic if Terra was the one saved before the final battle, but it would be even moreso if Ventus was as well since Aqua was presumed to be the relatively easy one.
Indeed, because his own body is where Xehanort's heart naturally belongs.
I also wouldn't put too much weight in Xehanort's ramblings as he likes to troll and mislead people.
Blank Points is still canon as far as we know and therefore Aqua was still normal without any Nortitis when she met Ansem the Wise on the Dark Margin, which takes place after KH II ergo during Re: Coded.
This means that IF Aqua is actually possessed by Xehanort (and to such a strong degree already) it has to happen in the time period between/during Re: Coded and Dream Drop Distance.
Hah, you can believe me that I don't want Xehanort to get his dirty abusive hands on Ventus' body either, yet if this "Nortqua" is the real thing and Aqua didn't manage to seal her memories away before Xehanort's influence took hold, he may have now indirect access to the Chamber of Waking through her.
Fact is the chamber cannot be accessed without Aqua, so Sora and the others cannot reunite Ven's heart and body/soul on their own.
If Aqua's truly possessed by Xehanort they also cannot take her anywhere with them as Xehanort could spy on
them through Aqua's eyes the entire time, just like Young Xehanort explained in DDD that Ansem SoD witnessed events through Riku's eyes during his possession of him.
In order for them to keep Ventus' body safe continuously, they would need to take out Nortqua somehow and work on neutralizing the Xehanort piece within her.
Due to my belief that Xehanort cannot really be decisively defeated as long as his spread out heart fragments still remain where they are, the good guys need to find a way to expel Xehanort pieces from within vessels anyways so maybe Nortqua will be used as an example case for it.
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I'm not even too sure if the "fated clash" between the 7 vs 13 is actually the true final battle, as in it might be only the opening round and in the actual final battle we will still get all the good guys united on the same side
against Xehanort instead of being forced to fight
for him.