http://www.gameinformer.com/b/news/archive/2016/01/15/pokken-tournament-lands-in-march-first-run-copies-come-with-shadow-mewtwo-amiibo-card.aspx
Pokkén Tournament has a release date in North America. Nintendo has announced that the game will drop in March for Wii U.
The Bandai Namco-developed Pokémon fighting game was released in Japanese arcades last year. First run copies of the home version will come with an Amiibo card featuring Shadow Mewtwo. Tapping the card on the gamepad unlocks the character for use immediately.
We’ve inquired with Nintendo if the Mewtwo card can substitute for an Amiibo figure in Smash Bros. We’ll update should we receive a response.
Pokkén Tournament will be out on March 18 for Wii U. Nintendo will also be re-releasing the original Pokémon Red, Blue,and Yellow on February 27. At the same time, a special New 3DS will hit stores with Red and Blue pre-loaded.
Update: The Shadow Mewtwo card only works with Pokkén Tournament.