Super Smash Brothers - The Source Behind the Dr. Mario Stage

First Rayman and now this.

1. Rule of Smash leaks: it's only real if Nintendo themselves try to cover the leak. Like the leaks from last year of the 3DS footage leaking to YouTube via the person in charge of sending footage to the ESRB turned out legit because the videos were question were explicitly removed by Nintendo (it said so if you clicked the links to the videos after they got removed). The Rayman "leak" however, when it was removed, didn't have that message, it said it was removed by the user (similarly, when footage of Ryu and Roy got leaked prior to the E3 Smash Direct, Nintendo forced YouTube to privatize all leak videos, though according to Etika no one got strikes on their channel for said leak videos).