This may have been discussed before, but I stumbled upon something that caught my eye in Nomura's interview for BBS Ultimania...

 

Nomura mentions, "In terms of the elements of Terra and Master Xehanort, I think the questions of how their power is related and divided, as well as who has whose memories and heart, will become a key to the story after this one," and in response to the question "Is that to say that there's a possibility that within Xehanort's Heartless, the darkness that sleeps in Riku's heart, there might remain something of Terra...?" he replies, "That's also a riddle connected to the next story, so everyone please use your imagination."

 

It appears that there will be a lot of focus on the special conditions of Terra and Master Xehanort (and Ansem SoD/Xemnas... Eraqus too, I suppose, as his heart is within Terra's), which is something that we take for granted, in that we don't really realize how much we don't know. Subsequent to the birth of Terra-Xehanort, all we know is of the existent of 4 beings - Apprentice Xehanort, Ansem SoD, Xemnas, and Riku-Ansem. Furthermore, we know nothing about what was actually occurring within each of them. We just know of their existence and their actions.

 

We have already seen one situation of abnormal separation - Sora's brief transformation into a Heartless, the release of Kairi's and Ventus' hearts (who were residing within Sora, just as how Terra's and Master Xehanort's (and Eraqus') hearts reside "together"), and the birth of two irregular nobodies (Roxas and Namine) as a result. It appears that the situation of Terra, MX, Eraqus, and Riku is much more complicated, and something that will play a significant role in "the next story," which is presumably DDD. To complicate the situation even further, we've got Terra's Lingering Sentiment, along with the return of MX and the mystery of Terra's location.

 

Suffice it to say, I'm even more excited now.

You're completely right. We hardly know anything at all on the subject. We have no idea how much each ego knows and remembers and of which life.

To be truthful, I think the creators of Kingdom Hearts have made the subject too confusing. They're never going to be able to fully explain the situation in future games, so we'll probably hear the rest by interview or we'll have it left to our imaginations and never be told.

... Huh?!

Precisely.

xemnas is more of Terra and ansem is more of xehanort you can tell just by their goals and how xemnas remebered aqua as and old friend and wanted to find were Ventus was

and there's the one thing that i think would start to bring KH down, if it came down to it. by now, i think they've left too many plot holes throughout the series to try to play catch up now and fill in some of the gaps. for example, we've known about namine since chain of memories, but we still don't know exactly what the story is of her birth. we know she's a special case of nobodies, if she even is a nobody at all, being born of kairi's heart/soul/body/whatever, yet being born when kairi's heart was released from sora's body, not from her own. and as a being that came into existence originating from a princess of heart, we don't know if that changes anything about namine or not (or at least, i don't). but, i'm probably over-thinking this by now, so i'll just shut up now.

and there's the one thing that i think would start to bring KH down, if it came down to it. by now, i think they've left too many plot holes throughout the series to try to play catch up now and fill in some of the gaps. for example, we've known about namine since chain of memories, but we still don't know exactly what the story is of her birth. we know she's a special case of nobodies, if she even is a nobody at all, being born of kairi's heart/soul/body/whatever, yet being born when kairi's heart was released from sora's body, not from her own. and as a being that came into existence originating from a princess of heart, we don't know if that changes anything about namine or not (or at least, i don't). but, i'm probably over-thinking this by now, so i'll just shut up now.

 

lol I've been thinking the same thing. But in Days they showed Axel looking at something called the Truth about Namine by Vexen, I believe. This may be referenced again in the future. I also think that ultimately, it will be something about Namine being born in order to save Terra, Aqua, and Ven.

Since Ansem and Xemnas have been destroyed to make Xehanort again, it's likely that Terra's heart is still in the darkness of Riku's heart. Although it's probably not that simple...I'm really excited about the next one too, because all of these technicalities have been driving me crazy too!

Since Ansem and Xemnas have been destroyed to make Xehanort again, it's likely that Terra's heart is still in the darkness of Riku's heart. Although it's probably not that simple...I'm really excited about the next one too, because all of these technicalities have been driving me crazy too!

 

It would make sense. It would explain why Riku fell to the darkness so easily in KH1. It could be a recurring element in DDD regarding the Mark of Mastery, it may even turn him into a villain for a portion of the game, or maybe even throughout KHIII.

 

As for my own theory I think this is why Ansem SoD was so interested in Riku. Before he manifested in Riku, he appeared as a ghostly hooded figure. It could be that part of Terra's heart still exists within Riku and that part may have been crucial to Ansem's plans. We really can't know for sure till we play through 3D but the way Nomura foreshadowed this definitely means that what he is planning will change Riku as a character forever.

Yes that is rather interesting. But he could have meant KH3 rather than DDD.