8 Players
Kid Icarus and Star Fox conversations on respective maps
Bowser Jr. Trailer
Painting screenshots
Mewtwo revealed for DLC
Stages
Amiibos
multiplayer classic and all star mode
Events
Masterpieces
Soundtrack CDs
Mario Pary-Smash Bros Hybrid taking place of Smash Run
3DS as controller
Master Core's new forms (Master Vortex, Master Fucking Fortress) Also, his sword form is called Master Edges.
Skill based Classic mode
Multiplayer Stadium, Trophy mode, and That bomb one
Some mode where you place trophys down and take pics of them
Custom Maps
Item Frequency
Thats about all i can remember at the moment
Edit: I forgot:
Spoiler
Ridlely is confirmed
Spoiler
as a boss