Nintendo could potentially make big money by releasing new characters and stages as DLC for Super Smash Bros for Wii U, just as they did with Mario Kart 8. But the creator and game designer Masahiro Sakurai says there is no such plans in an interview with Video Gamer:
"I understand that DLC could add a lot to the appeal of Smash Bros, and I appreciate that a major part of the excitement for these games come from which characters will appear in the roster, so I think fans could really enjoy DLC that could keep this excitement going. However, I think there might be criticism that we are cutting up content to sell characters one by one, or that we are adding things later that should have been there from the start."
And because of this very reason, he most likely isn't going to do it:
"However, what I can say now about paid DLC is that we aren't working on anything at the moment. We've put all our efforts into making the actual game."
Before ending the interview, Sakurai also shoots down the idea to let the Nintendo executives Reggie Fils-Aime, Shigeru Miyamoto and/or Satoru Iwata join as fighters in the game:
"I don't think the inclusion of these characters would be very interesting to a wide audience."
