Super Mario 3D World + Bowser's Fury

New levels in the main game, new difficult levels in Bowser's Fury if it's supposed to be hard mode, and probably one new character. Daisy, Yoshi, and Pauline are my guesses.
 
This actually looks really cool, it's definitely way more than just a run-of-the-mill 3D World expansion. Props to Nintendo on this one, I wasn't really planning to pick this up but I might have to now.