SPOILER, SPOILER, SPOILER. Please only read this if you have already played Birth by Sleep or don't mind spoilers, for what lies under the cut relates directly to BBS. While it may not be directly applied to the way I play Riku right away, these are my thoughts on the new canon and how I will be interpreting it ICly and how it fits in with previous games. So, without further ado...
A Chance Meeting...
Riku has a relatively small role in Birth by Sleep, but said role is still crucial to his character in future titles. BBS reveals that there is much more to Riku's actions and Keyblade wielding, not to mention his longing to see the outside world.
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In this scene, we see how Riku's destiny unfolds, as it's revealed just how Riku was chosen by the Keyblade.
Meeting Terra is something I consider very significant in his life, even though they only met once. For the first time, Riku got to see someone from the outside world. More importantly, Terra seemed to know a lot about the outside world and was willing to listen when Riku explained just why he wanted to leave the islands. Rather than reprimanding him and telling him he was just a kid, Terra even performed the rite of succession on Riku. In promising the Keyblade to Riku and a way to the outside world, Riku's outlook on his home probably changed, even if only slightly.
Some might argue that, because he was a kid, it shouldn't matter, but you have to remember that this is Riku. The outside world fascinates him and always has. Not only that, but, as a five or six year old, he's very mature. If anything, his meeting with Terra isn't something he could so easily forget. It was more than just a meeting with a stranger; Terra essentially promised to show him the way, someday. Thus, I believe the only reason why he acts so clueless about the Keyblade in future titles is because he had to keep it a secret, or the "magic [would] wear off".
It puts his actions in KH1 into a different perspective, too. While he claims that Kairi's the only reason he thought of the raft, that doesn't mean she's the only reason he wanted to go to the outside world. It was a secret, so of course he'd keep quiet. Kairi's appearance probably just increased his longing to see more worlds and gave him incentive for the raft, as she washed up on shore during a meteor shower. Also...
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(skip to :42)
So... this is called a Keyblade?
Let's assume Riku remembers seeing the Keyblade. It changes the meaning of this line. Upon seeing Sora with the Keyblade, Riku probably remembered his exchange with Terra and snatched the Keyblade to get a better look. Having no idea what the weapon was called, his question now acts as a double entendre. To Sora, it's as if he's seen the Keyblade for the first time, while Riku is probably curious about the weapon itself and why Sora has it.
Later...
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Let the Keyblade choose... its true master!
It's very likely that Maleficent told him to steal the Keyblade from Sora. While how she knew he was the true wielder remains a mystery, it's still doesn't mean she's the only reason he took it. Because he believed Sora was on the wrong track and because of his exchange with Terra, this further justifies why he considered himself and, indeed, was the true wielder of the Keyblade.
He just failed to keep it due to his selfishness. However, that doesn't mean the power to wield is gone. Let's take a look at this Nomura quote...
Tetsuya Nomura: "Since Riku has always been using Soul Eater, he still calls it that even after it changed form. Keyblades aren't something that you can obtain suddenly out of nowhere so in Riku's case, his Soul Eater was used as an intermediary for that Keyblade."
His heart, having been chosen all those years ago by Terra, was still capable of wielding a Keyblade. All Riku had to do was conquer his own darkness and, bam, Way to the Dawn come KH2. Given this fact, it's likely that he could have obtained said Keyblade a long time before that, but come the end of CoM and Days he just falls deeper and deeper into the dark and winds up caught in the middle of DiZ's schemes, which probably didn't help much.
The fact that I choose to have Riku remember Terra still might be questionable to some people, but, again, his fascination with the outside world and how significant their meeting was probably had a lasting impact on Riku. And, if Riku remembered the Keyhole in the Secret Place years later, why not Terra as well? Kids don't forget everything. Besides...
-- By the time of "KHI", have Sora, Riku and Kairi forgotten about Terra and Aqua?
Nomura: That's right. In "KHI" Kairi herself says that she's lost all her previous memories, that she "doesn't remember anything before coming to the Destiny Islands", and it would be pretty easy for Sora to forget. After all, I think for a child of 4 or 5 years old to remember a person they met only once and exchanged just a few words with would be quite unnatural. Only Riku, who was told by Terra "Don't tell anything of today to anyone," may simply be keeping quiet.
This is what I choose to believe. My own personal headcanon is that he probably jotted it down so he wouldn't forget. Riku's very smart for a boy his age, giving a lot of insight during his conversation with Terra, so I don't think it's really a stretch. Now, for Aqua...
Click to view
I think in this case, Riku's memory might not be so strong. He might recall meeting a lady from the outside world once, but because their meeting wasn't quite as significant, I'm sure he forgot the exact context of the meeting. He didn't know she wielded the Keyblade, and all that stuff she said about darkness is something he likely brushed off as a child. I think that if he saw Aqua, he'd find her familiar, but, unlike Terra, he wouldn't immediately recognize her, nor would he remember what she said. Ten years is a long time to remember something less significant.
Lastly...
Q5: Why was Riku chosen as the original wielder of the keyblade?
A: Because he was chosen by Terra to inherit.
To use a keyblade you must have been chosen to inherit as well as been chosen by the keyblade itself. In BbS you could see that Terra performed the ceremony with Riku, and that is why Riku was able to take the keyblade that Sora used.
[picture: Little Riku and Terra]
Terra looks at Riku as he performs the inheritance ceremony.
[picture: Little Riku looks at a door with a keyhole.]
Because he has been chosen to inherit, Riku can see the keyholes of the world.
What this means...
• Riku's known about the Keyblade for years. Even when he first arrived in Luceti, he'd seen it before, even if the name and its true potential were a complete myster. He just never made it known because he promised to keep the truth under tight locks. Part of his longing for the Keyblade prior to his update was indeed because of Terra. To see his best friend with a weapon that was promised to him hurt. However, because it's a secret that he still honors even now, he couldn't just tell anyone one of the more crucial reasons for his jealousy.
• Riku remembers Terra. He doesn't know his name, and he might not remember his exact appearance, but he remembers their meeting and the bare basics of what he said to him. Were he to see Terra again, he would recognize him and probably be very eager to talk to him, if not a bit wary. After all, as he's post-CoM now, he'd probably worry that he hasn't lived up to the man's expectations. Rather than being the "champion [of] those [he loves]," Riku let the darkness get to him, and his selfishness got in the way of what really matters.
• He doesn't remember Aqua very well. If he were to see her, she'd probably feel familiar, and the name "Aqua" might ring a few bells, but it'd take a lot more for him to really remember their meeting. What she said he's forgotten completely, unlike with Terra, as her talk of darkness was just confusing at the time. Still, as a complete stranger to the islands, I can see Riku at least recalling her presence as a strange lady from the outside world.
• As shown in the above video, Riku has more than one reason for his longing to see the outside world. First, there's the story of a kid who left he islands for good and saw the outside world. Then, there's Terra, who chose him as his successor. Third, there is the Keyhole to Destiny Islands, which he saw as a child. Finally, there is Kairi, who inspired him to build the raft.
• As a child, Riku was a very kind boy who genuinely wished to protect his friends. As time went on, though, he started to drift further and further into the dark, and while he's always had good intentions, his selfishness and jealousy clouded his views. Everything he did in KH1 was for a reason, though. True, his motives were twisted by a huge misunderstanding, but his cruelty to Sora was in part because he wanted Sora to come to his senses and care about his best friends. Also, his longing to save Kairi was very genuine, even if he went about it the wrong way.
Also, this puts the line "Riku's changed" into a new light, because it's clear that he indeed has changed since he was a kid.
More general headcanon to come, once I do the meme, most likely. For now, this is just the information I've formulated upon playing BBS along with some tidbits from the Ultimania.