Pokemon X and Y will be introducing a brand new gameplay element--one of the biggest changes to the core Pokemon battle system. "Mega Evolution" will allow Pokemon to transform to new, more powerful forms in the middle of a battle.
The latest issue of CoroCoro shows off a number of Pokemon in their "Mega" forms, including Mega Blaziken, Mega Mewtwo (pictured), Mega Lucario, and more. "Mega" forms will not only have new abilities, but may also feature different elemental types. For example, Ampharos turns into an Electric/Dragon type after Mega-evolving.
Pokemon fansite Serebii.net has been keeping track of the Mega Evolutions announced so far. As the site points out, the method of triggering Mega Evolution is unknown, but may use a new consumable called "Mega Stones."
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