The Nintendo 3DS version of Super Smash Bros will feature an exclusive mode called Smash Run: a 4-player battle game set in a dungeon-like stage full of power-ups to collect. You can explore the stage & collect power-ups for 5 minutes, then slug it out with your enhanced fighters.
I think this is the 3DS’s version of a co-op story mode….not much story, but it looks fun. Guess the Wii U version will have an exclusive mode of its own, its “Story” mode. I hope the classic mode is still there where you fight 10 guys then Master Hand lol.