Sakurai said that they had a working version of the Ice Climbers on the Wii U version but the 3DS hardware just couldn’t handle them. The team wanted the rosters to be the same so they dropped the Ice Climbers from the game.

Maybe they finally got Ice Climbers to work on 3DS with the new 3DS update! Maybe Shovel Knight is gonna dig his way in! Maybe we’ll see King K. Rool cannonball his way into smash! Maybe Nintendo is slowly brainwashing us because of Smash bros!! *insert insane person gif here*

That’s only mildly terrifying