What is "This world"? It's not a game mode but it's related to the game modes. They obviously did this one backwards with the ??? in order to get us wondering.

Oh yeah, what el Duderino said works to. For skill, some battles with items, some without.

What is worse than having a crappy update after a long weekend? Having an update before the weekend that raises more questions than answers. That's what.

It says it's a game mode... I don't know what's going on >_<

Also, is the background for that entry black for anyone else?

-edit-
And I only suggest it's from a movie because of the angles  and animations (Mario's eyes and such).

What is that supposed to be???

??? Yeah what's the last pic supposed to be.

I wonder if it is a 3D battle arena....or an extension of the story mode. Or maybe it is one of many story modes?

I'm guessing it's one of the modes like Adventure or Classic? Trophy fighting...err...or perhaps the opening? An explanation of why they're smashing?

And some don't...follow the rules? Meta Knight...? And...weird thing at the end...wtf!

What is that thing?