Starting on August 13th, Pokémon X and Y players in the United States and Canada will be able to download the version-exclusive Pinsir and Heracross, and the Mega Stones necessary to Mega Evolve both.
That means Pokémon Y players can grab the Bug-type Pinsir, normally an X-only encounter, and Pokémon X players can grab the Bug and Fighting-type Heracross, normally a Y-only encounter.
On August 18th, participating GameStop stores will hand out codes for Pokémon X and Y players to unlock Mega Stones for both Pinsir and Heracross.
In battle, the Heracronite stone Mega Evolves Heracross into Mega Heracross, while the Pinsirite stone Mega Evolves Pinsir into Mega Pinsir. Codes are in limited supply, and are seemingly exclusive to GameStop stores in the United States.
Cross-version accessibility to both Pokémon ends on September 17th, so catch 'em while you can, starting August 13th.Game Informer
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