The Pokémon is obtainable through codes which are being given out by Gamestop in the US and by EB Games in Canada. The event runs until the 31st of October and the Volcanion's details are as follows:
Ability: Water Absorb
Held Item: Assault Vest
Moves: Steam Eruption.
The event is also currently running in the UK where GAME are supplying the codes. The event began in the UK on the 1st of October and runs through until the 23rd of November, the day the new games Pokémon Sun and Pokémon Moon officially launch across Europe.