ANGEL LAND
Pit's home battlefield is likely this scene from his game, Kid Icarus.

CASTLE
This dark, mysterious castle is believed by many fans to have been borrowed from Fire Emblem... However, there's no official word yet on the possible return of Marth and Roy.

MARIO KART
This stage was inspired from the popular Mario Kart series, and features Shy Guys driving go-karts. The concept seems to be similar to the Mute City track from Melee, which was of course based on F-Zero.

METAL GEAR
Solid Snake slithers up behind Samus, in a scene that was borrowed from the Metal Gear universe.

META KNIGHT'S AIRSHIP
An epic battle between Kirby and Meta Knight, in one of the coolest looking new arenas.

STAR FOX STAGE
A spacecraft hovers over what could possibly be Coneria...

POKÉMON STADIUM
With a few more Pokémon characters expected, it's no surprise that Pokémon Stadium is once again featured as an arena.

YOSHI STAGE
One stage closely resembles something you'd see in Yoshi's Island 2 or Yoshi's Story... This is quite suggestive that Yoshi will also be back as a regular character.

SNOW STAGE?
Not completely sure if this winter wonderland is a stage or not... It might be part of an adventure mode landscape, because it doesn't look like a battle arena.