It's not likely. But, of course, it'd be cool. As for the "feel", when controlling Sora or Riku, I don't think there'd be much of a difference, if he were playable that is. But, I think that controlling BHK, would kind of be like controlling Riku, even if we haven't been giving the chance to play as Riku, (excluding CoM) but based on their "build", they both seem very agile, and capable of powerful finishing blows. And if you look back to ASAS and DD, based on BHK's "defying of gravity", you can expect very quick kills, and tite @$$ moves.
Feel free to flame.
j
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