Did you know that in Super Smash Bros Melee, Captain Falcons' red costume was originally planned to have a "Blood Falcon" emblem on his back, and was originally planned to say "Hell Hawk"?
Did you know that in Super Smash Bros Brawl, multiple unused character data files were found in the disc? These include:"dixie ,"dr_mario", "mewtwo, "roy","Pra_Mai","toon_sheik", and"toon_zelda".
Did you know that in Super Smash Bros Brawl, Pokemon Trainer has an unused jumping animation? This may hint that he was originally a planned to be a playable/separate character.
Did you know that in Super Smash Bros Brawl, in the text data for enemy names, a few unused names exist, implying enemies that were cut? These names include:
Melorin
Mechaboom
Bublit
Blowm
Plowm
Aliians
Aliian
And Mizzo, even though they can be found in the background for the Battleship Halberd.
Source:http://www.ssbwiki.com/Beta_elements