It's hard for me to believe in "leaks" or actor/company released "spoilers" at all anymore. Not that people don't make the occasional mistake, but every week it's, "Game of Thrones actor drops unbelievable spoiler!!!!" that just happens to barely give anything away and is just obscure enough to get everyone talking. B.S. I think it's all a gimmick to get you talking about the game or film, building hype for a product and getting cheap press.
Take this new TV spot for Super Smash Brothers Ultimate, for example. It's tough to believe that somehow, in a 30 second TV spot, ALL OF NINTENDO somehow missed this giant leak in the first five seconds? They accidentally had the new, as yet unreleased and unmentioned mode on the friggin TV screen that the camera opens on? Yeah... I'm not buying that. What I think is going on, is they put that in there, a million "journalists" all squealed because they think they are jr. detectives (ha-ha, Nintendo! You have to get up pretty early in the morning to advertise a new model to me!), and now, it's working like a charm. Everyone is talking about it, including me, so I guess I'm a dumbass after all.
But here ya go; if you want to squint your eyes tightly and cock your head, you can make out "stage builder" at the bottom of this screen.
The first stage builder was released on Smash Bros Brawl for the Wii, and Stage Builder debuted for Super Smash Bros. Brawl on the Wii and allowed players to create their own custom stages to beat the crap out of their buddies by using stuff from other stages, plus songs and backgrounds to really make the stages your own. It looks like this mode will be returning for the Switch. Stay tuned, maybe they'll "leak" the release date next.
Take a look at the video below to see the entire commercial.