Here's a theory that a friend told me:
It's possible that the same way Ansem SOD possessed Riku, MX possesses Terra, since he and Xehanort have a similar hairstyle. And the reason why Terra appears in KHII as "The Lingering Sentiment" could be that once Xehanort turns into a heartless, he gives life to Xemnas and Terra's heart is released, or at least part of Terra.
Where is Master Xehanort? He's now the guy that's trying to possess Riku and take over Kingdom Hearts, and that's why Ansem wear's the same clothes as Master Xehanort, because HE IS Master Xehanort!
As for Ventus, the same way Kairi's heart was somehow stored into Sora, so could be Ven's, due to something happening in birth by sleep. When Sora stabbes himself with the dark keyblade, Kairi's heart is released, and so is Ven's, and as Roxas is created, Ven's heart finds Roxas's body. That's why he looks exactly the same as Ven and acts as if he had a heart.
What do you think?
It's possible that the same way Ansem SOD possessed Riku, MX possesses Terra, since he and Xehanort have a similar hairstyle. And the reason why Terra appears in KHII as "The Lingering Sentiment" could be that once Xehanort turns into a heartless, he gives life to Xemnas and Terra's heart is released, or at least part of Terra.
Where is Master Xehanort? He's now the guy that's trying to possess Riku and take over Kingdom Hearts, and that's why Ansem wear's the same clothes as Master Xehanort, because HE IS Master Xehanort!
As for Ventus, the same way Kairi's heart was somehow stored into Sora, so could be Ven's, due to something happening in birth by sleep. When Sora stabbes himself with the dark keyblade, Kairi's heart is released, and so is Ven's, and as Roxas is created, Ven's heart finds Roxas's body. That's why he looks exactly the same as Ven and acts as if he had a heart.
What do you think?