Roxas obviously has a large role in KH3, with Nomura two days ago* stating,"Roxas is the utmost secret for Kingdom Hearts III. He's the top secret actually for Kingdom Hearts III so I really can't say anything about him."  When we see Xemnas addressing Sora in Twilight Town he tells him that the only way to free Roxas is to open himself up to Darkness. This honestly isn't that huge of a reveal, seeing has Roxas was created when Sora unlocked his heart in KH1 and became a Heartless temporarily. 

 

So it seems that Sora will, in order to bring Roxas back, will unlock his heart again in some way to achieve it,intentional or not. I think this only begs to ask why Roxas is so central to this part of the story, and seeing as Vanitus will be hunting down Sora for his other half I think that the two, being Roxas and Ventius, will be extracted from Sora at the same time.Everything seems to be leading up to that, but it's all just speculation at this point. Please let me know what you think!  

Edited June 14, 20187 yr by Fullmetal Keyblade

If only Roxas and Ven were not the same, because they are even depicted in DDD.

Don't forget, they also talked about the Data Twilight Town and how Ansem may have included Roxas's data in there. That's probably gonna play a role in his return, no matter how big. Maybe by "analyzing" that data, they might even find a way to bring Ventus back, separately from Roxas. We still don't know what kind of data Ansem provided Sora and co. and how important it is. He did say that it's gonna help them find their lost friends.

Edited June 14, 20187 yr by Nick Sideris

I mean this is where the importance of Re:Coded comes in! What they're trying to do is to somehow bring to the real world Roxas's Data body from the Alternate Twilight Town, that way he can be his old self in 'terms of memories and stuff and then place "his heart" inside that data body to bring Roxas back. We saw that Data Sora claimed a real Keyblade in Re:Coded since he became "more than the system" and got a heart somehow (or created one or so), this being an example of how Roxas can come back withouth affecting Ventus's body in the process, the problem here is how to release his heart and Ventus's without losing Sora.

I mean this is where the importance of Re:Coded comes in! What they're trying to do is to somehow bring to the real world Roxas's Data body from the Alternate Twilight Town, that way he can be his old self in 'terms of memories and stuff and then place "his heart" inside that data body to bring Roxas back. We saw that Data Sora claimed a real Keyblade in Re:Coded since he became "more than the system" and got a heart somehow (or created one or so), this being an example of how Roxas can come back withouth affecting Ventus's body in the process, the problem here is how to release his heart and Ventus's without losing Sora.

 Exactly. And Sora is already being hunted by the Organization, which is why it seems that Vanitus will have a part in extracting at least Ventus from him. Vanitus needs his other half after all, I don't think he sees Sora as enough of a threat to not simply resort to defeating him and releasing his heart. I absolutely believe Sora is strong enough to give him a heck of a fight however, but seeing as Sora is, again, being hunted by the Organization, it's difficult not to see that happening in some way. Sora was almost taken completely by Xehanort in DDD after all, he must be seen as vulnerable target to the Organiazation. Noruma himself stated that this game was going to be darker than what we're used to in KH, and there will be surprises that he hopes we'll be okay to handle. Sora being defeated by the Organization in order to bring back Ventus and/or Roxas doesn't seem too far from the realm of possibility.

Edited June 14, 20187 yr by Fullmetal Keyblade

If only Roxas and Ven were not the same, because they are even depicted in DDD.

Roxas and Ventus are not the same.

Roxas and Ventus are not the same.

Yes, I know this, but damn it immediately comes to my mind the situation with Rose and Pink Diamond from Steven Universe. And the fact that with the appearance of Aquanort, I'm waiting for anything from Nomura. But I would not like that either.