A brand new feature of the Pokémon X & Y games are Mega Evolutions. These are special features of Pokémon, different to evolutions and forms, that have your Pokémon Mega Evolve in battle into these appearances.
Their abilities, stats and sometimes even types are different. To get a Pokémon to Mega Evolve, they need to be holding a special Mega Stone item unique to their species. To get your Pokémon to Mega Evolve, you can select a button when picking the move and then select a move. The Pokémon will both evolve and attack in that turn. You may only have one Mega Evolution in a battle.
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