I just wanted to say if you think about it, the "glowing eyed unknown" is most certainly Roxas, because Roxas is Sora's nobody. The unknown standing at the beach is DiZ (voice recognition) and he says " he looks just like you". An unknown also says this to SORA in KH Final Mix, which would make it appear that the "glowing eyed unknown" is either Sora or Roxas, and I say Roxas because its Roxas' dream, and also may be a memory from when he was in the Organization, thus the cloak. There, think about that, do some research, and let me know what you think.
Have you ever played Kingdom Hearts 2?