Uhh guys do you realize when you go to yen sids tower at the beginning of the game there are five mirrors one for each drive form and you need to reread two of them
Master: you see yourself unlocking the keyblades unlimited power
Final: You see yourself possessing all abilities ( And it is not talking about stuff like leaf bracer )
Plus on top of that since this is out of game he wouldn't have a gauge so he'd go into final and revert at the end of the battle
FYI: when he go's into either of those he loses donald and goof which mens he has plenty of experience fighting without them
P.S: Go to youtube and look up videos of sora in final form... if I had to fight someone like that scratch that if I SAW someone like that I'd **** my pants