those codes have been discovered and out for a long time.you can only play as the party members in their specific worlds (ie:auron at underworld,alladin at agrabah)but they only have the attacks they usually do.you cand do other attacks besides the ones they got.
It looks cool, but I'd imagine that they aren't very efficient with their lack of attacks. And as people have said, I'm pretty sure I've seen this kind of thing around for a while.
I was actually talking about controlling him. I know it would take codes to do that. I am aware that it is old, but I am a little late in finding things like this a lot of the time.