Quote:
Sora can "merge" with either Donald or Goofy to become a completely different version of himself. When merged with Goofy (Valor form, Brave form in Japan), he wields dual Keyblades (Kingdom Key and Oathkeeper by default), becomes a combo-chaining, full-offensive character type with additional attacks, dons red clothes, and cannot use magic. When merged with Donald (Wisdom form), his Keyblade's length increases and is wielded in the opposite hand, gains a massive magic attack boost, replaces the attack command with a command that lets him shoot a white magic bullet from the tip of the Keyblade, dons blue clothes, and glides across the floor instead of running. A third form, Master, combines the powers of Valor and Wisdom forms: two Keyblades can be wielded (Kingdom Key and Oblivion by default, with Oblivion appearing to be physically held), his clothes will turn yellow, and he will be able to fly. While Sora's Drive Bar will decrease more rapidly when in Master Form, he will wield greater power. A fourth form is called the Final Form. Not much is known about this form except that Oathkeeper and Oblivion are shown with it and that Sora dons whitish-silver clothes.
It says that Keyblades can be changed in both the Valor and Master forms, and seeing that the master form can fly, I wouldn't be surprised if the 'final' form can too.