The Pokémon of Super Smash Bros. for Nintendo 3DS / for Wii U in pictures, according to Poképédia.

The Super Smash Bros. for Nintendo 3DS / for Wii U logo.
Pikachu in Super Smash Bros. for 3DS / Wii U.
Lucario.
Charizard.
Greninja.
Jigglypuff.
Mewtwo.
Greninja uses Water Shuriken.
Lucario uses Aura Sphere.
Charizard uses Flamethrower.
The Unova Pokémon League stage.
The Ironworks Chamber, Kalos Pokémon League.
The Blazing Chamber.
Axew in the Dragonmark Chamber.
Lugia released from a Master Ball.
Palkia released from a Master Ball.
Xerneas.
Meloetta and Relic Song.
Dedenne released from a Poké Ball.
Gogoat released from a Poké Ball.
Chandelure in Smash Run.