I'd rather have Roxas not care instead of being so angry at Riku over events neither of them had much control over, where the machinations of the Organization and DiZ's revenge made things more complicated than they should have.
And remember, Roxas was NOT in a stable mindset at the time, basically on a suicide mission where he was under the assumption that making contact with Kingdom Hearts would bring Xion back, and that he was gonna survive and go after Sora. Trying to talk Roxas out of this wasn't going to do any good. Riku had to take him down, otherwise Roxas would likely be dead either by way of the Organization, or Kingdom Hearts itself, and restoring Sora's memory and waking him up would be impossible.
I'm sure Roxas knows that by now.
Sorry for responding to this late, but you are absolutely correct in saying that Riku was almost just as much a victim of the machinations of DiZ and the Organization. Him appearing as SoD in KH2 is definitive proof of this. However, he's still very much responsible for his own actions, and his own moral logic still directly clashes with Roxas'.
Why was Riku fighting Roxas? To restore Sora to his complete state, yes, but then one has to ask, isn't he just sacrificing one person's existence for another's? What is it that makes Sora's life more valuable than Roxas' exactly? Well outside of their value to him
personally, really nothing. The true logic behind Riku's reasoning is that, rather than have Roxas go face the Organization and die a meaningless death (even if it's really not) and condemn Sora to the same fate, he could instead force the other to sacrifice himself for Sora and make sure that
someone comes out of this horrible mess alive. Riku, especially at that point, didn't really care whether or not Roxas lived or died, he just wanted to make sure his best friend came out ok, and was ready to get rid of whomever he had to in order to make that happen.
But here's the problem, and the thing that puts him in direct opposition with Roxas in every single one of their interactions: what gives Riku the right to decide someone else's fate like that? What gives him the right to strip Roxas of his one and only true moment of agency? Now the confused, desperate boy has to sacrifice himself for someone he doesn't even know or care about? Does he not get a say? Does he not even have the right to
know? That's the EXACT same logic that Roxas shamed Axel (and later DiZ) for before he defected from the Organization, and what caused their falling out in the first place. Except, at least with Axel, Xion actually
chose to "return" to Sora of her own volition, and he merely allowed her the freedom and choice to do so. Additionally, while Xion was, to a degree, directly responsible for syphoning off Sora's memories and had the knowledge and agency to act against this fate, Roxas wasn't responsible for that, what Namine did to Sora in CO, what happened between AtW and his apprentices, or Xemnas' plan to keep Sora from ever waking up. He was completely innocent, and had little to no agency in any of the things that took place, so he of all people shouldn't be paying for everything with his life.
But then what do we see Riku do after this? If he was truly guilty, he would at least give Roxas the information he nearly risked his life to obtain, right? For as much as I don't like Namine in the KH2 prologue (though I do love her character as a whole), at least she was willing to tell the truth to Roxas before he disapeared. Riku on the other hand,
continued to subvert Roxas' agency at every turn, while saying things like "It's best he doesn't know the truth." Again, that's the exact same logic that made Roxas lose whatever trust he still held toward Axel (his best friend) at the end of 358/2 Days. There's no way in hell he wouldn't hold Riku accountable for housing such a mindset, and unlike with Axel, who was trying to keep Roxas "alive" (for lack of a better term), Riku was actively trying to sacrifice him. Now, that's not to say I don't think Riku felt guilty about forcing the other into such a situation, but the closest thing he ever shows to sympathy is mild pity toward Roxas.
"Poor thing." (Note how he says "thing" here, and not "guy").
By the time Roxas finally gained his memories back, he not only still hated DiZ, but held such a high level of contempt for him that he viscously tried to hack the man to death... Multiple times. I'm about 95% sure that if it were Riku in place of DiZ in that scene, he would've reacted almost, if not the
exact same way.
If we really wanted Roxas to be on better terms with Riku, then what we should've gotten was some kind of four-way conversation between him, Riku, AtW, and Namine. In which Roxas scolds the two of them for their gross mistreatment of him, and when he zeroes in on Riku, that'd be when Ansem explains that Riku was just a victim of his own plans for revenge, and that if anyone's to blame, it's himself. After that, Namine would likely bring up how she technically could've separated Sora's memories from Roxas and allowed them both to co exist if she had more time. Time that Ansem wouldn't allow her (this was all stated back in 358 btw).
Once that was said, whether or not Roxas fully forgave Riku, the two would still likely be on much better terms, and it would feel far more organic than having Roxas drop everything for no real reason.
Do you see what I mean here?
I mean in the midst of a Keyblade War, I really don't see any characters having any actual opportunity to wrap up things. I mean, when Roxas returns the moment is way more important to RAX rather than Riku running in and saying "sorry about everything Roxas and Xion". That's the issue with KH3: the structure of the plot just didn't allow these moments that should have happened to occur organically. If Roxas returned before the Keyblade Graveyard, Riku was in the Realm of Darkness for most of the game. It would have been weird to just shove a scene between Riku/Roxas that had essentially nothing to do with the plot into the Mysterious Tower segment.
Precisely! What people need to understand is that KH3 clearly wasn't built or structured in a way that would allow the writers to include these sorts of interactions and conclusions. Rather, it was designed so they could actively
avoid having to deal with addressing these things, while simultaneously shoving in sequel bait to fill up the time. That's why we have weird moments like Ansem The Wise being kidnapped by SoD before the game even starts, only for the two to
just arrive in Twilight Town toward the end of the game for zero reason, and now no one else besides the apprentices even know AtW is alive and in the RoL (so he can't get any closure with Roxas, Namine, Riku, Mickey,
or Aqua). Or how about the fact that despite Ienzo
litterally having a replica hand deliver to his feet, and Sora unlocking the PoW at about the same time, neither of them ever bother to contact eachother for the rest of the game (even though Sora openly laments not having Roxas and Namine present with everyone else, so logically he has every reason in the world to bring this up, but doesn't..)? And of course, let's not forget how Roxas and Sora didn't exchange a word with eachother after the former finally returned, nor did Roxas really speak with Xion or Axel.
How is that supposed to be satisfying, or even justify all the
egregious amounts of build up for Sora and Roxas to finally meet and interact again as
equals (which should've helped firmly establish a new status quo, as well as their shared dynamic)?
I could go on, but the point is, it's not that KH3 couldn't have had all these important interactions, but the writers never bothered to structure the narrative in a way that supported or encouraged them in the first place. Most likely because they didn't really care, despite certain statements being made leading up to the game's release. Even the (mediocre) interactions we DO get are incredibly awkward and stiff. Which is a general criticism that extends to most cutscenes in the game actually. The Mysterious Tower scene, for example, genuinely makes me uncomfortable due to how stiff and rigid the characters felt during their exchanges (and the diologue itself held numerous contradictions that don't flow with the rest of the story, almost like it's in some sort of vacuum), and it came off like this weird "check off the list" moment. There aren't many peices of diologue exchanged between the original characters that feels organic and earned (with very select exceptions), and the way certain conversations are actually
prompted just comes off bland and forced.
In the end, I'd say KH3 desperately needed a reworking of it's fundamental story structure, as well as more fleshed out and
consistent character writing.
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My headcannon is that the whole game was just a scrambled dream Sora had before he woke up in Shibuya, and not
actually what really happened (though that would still imply Sora "dies", which robs us of a proper conclusion, but at this point, I really couldn't care less, lol).