The following information was translated from a Nintendo Dream interview with Masahiro Sakurai...
- Decidueye was almost chosen for the new Pokémon spot
- Zelda is confirmed to be based on Link to the Past AND Link Between Worlds
- Xenoblade 2 and ARMS characters just had bad timing for the project plan
- Belmont boys, Ridley and King K Rool were added due to the Smash Ballot
- King K Rool's concept was to be a heavy, but do things that a heavy character normally wouldn't be able to do
- Piranha Plant was decided because it's a character that isn't a hero. Sakurai and the team felt if all the characters were heros it'd be a bit boring. Also, the Piranha Plant is well known