Disney has now taken over LucasFilms along with Marvel and so it could mean that characters from Marvel and StarWars will show up alongside Sora.
Tetsuya Nomura has been very excited about this prospect, but he said that getting Captain America, Iron Man, Darth Vader and Obi Wan Kenobi had not been easy. He went on to say that there were so many rules and regulations in place even if Square Enix and Disney worked together closely.
However he did say that there would be some surprises coming with additions to Kingdom Hearts 3.
KDramaStars said that there is a rumour going around that may suggest we could see Iron Man make an appearance in Kingdom Hearts 3. It was said that the superhero would recruit Sora as he was looking to beat Darth Vader.
Of course this is just a rumour that has been going around. We will have to wait and see what happened at the E3.