I have no idea how much or little sense this makes, but whatever. It's unclear what the Key to Return Hearts DOES, but assuming it... Returns Hearts, it will likely be used to help Ventus (whether it's a physical item, a spell, a person, whatever). But there are three people in a situation very similar to Ventus', with one key difference. None of them have bodies for their Hearts to be returned to.
Ansem the Wise makes it clear that the last thing needed in order to save everyone is his own research on Hearts. And what was a huge part of Ansem's research? Data. We are likely not done with data worlds, and Ansem has already created two, the Tron copy and the digital Twilight Town.
Data doesn't dream and data has no own memory due to data worlds having no hearts, and as such it's easier to mess with than human beings.
Since Ansem wants to help make up for what he did and what he says when talking to Riku in Dream Drop Distance, and to Aqua in Blank Points, his research has a lot to do, specifically, with the savings of Naminé and Roxas (and Xion, by virtue of her being in the same situation as them, even if AtW couldn't remember her when he put the research into Sora).
So, the general idea would be to, instead of putting these three Hearts inside of a body that doesn't exist, put them in a data world instead. Growing a Heart made Data-Sora able to mess with the system enough to get his own data Keyblade created from his own Heart as opposed to created by someone else like his original one. As such, if you put a Heart with a memory of how they used to look like, and the memories of those connected to them, the data world would be manipulated into creating a body for that Heart.
If it's possible to digitalize a real body into data without issues - this is done multiple times in KH2, between Space Paranoids and the data Twilight Town - it should, then, be just as possible to turn a data body into a real one just by reversing the process.
And voilà, three new bodies, created from the Hearts of Roxas, Xion and Naminé.
I have no idea how much or little sense this makes, but whatever. It's unclear what the Key to Return Hearts DOES, but assuming it... Returns Hearts, it will likely be used to help Ventus (whether it's a physical item, a spell, a person, whatever). But there are three people in a situation very similar to Ventus', with one key difference. None of them have bodies for their Hearts to be returned to.
Ansem the Wise makes it clear that the last thing needed in order to save everyone is his own research on Hearts. And what was a huge part of Ansem's research? Data. We are likely not done with data worlds, and Ansem has already created two, the Tron copy and the digital Twilight Town.
Data doesn't dream and data has no own memory due to data worlds having no hearts, and as such it's easier to mess with than human beings.
Since Ansem wants to help make up for what he did and what he says when talking to Riku in Dream Drop Distance, and to Aqua in Blank Points, his research has a lot to do, specifically, with the savings of Naminé and Roxas (and Xion, by virtue of her being in the same situation as them, even if AtW couldn't remember her when he put the research into Sora).
So, the general idea would be to, instead of putting these three Hearts inside of a body that doesn't exist, put them in a data world instead. Growing a Heart made Data-Sora able to mess with the system enough to get his own data Keyblade created from his own Heart as opposed to created by someone else like his original one. As such, if you put a Heart with a memory of how they used to look like, and the memories of those connected to them, the data world would be manipulated into creating a body for that Heart.
If it's possible to digitalize a real body into data without issues - this is done multiple times in KH2, between Space Paranoids and the data Twilight Town - it should, then, be just as possible to turn a data body into a real one just by reversing the process.
And voilà, three new bodies, created from the Hearts of Roxas, Xion and Naminé.
Thoughts?