Update: The free Shiny Gengar can be yours at GameStop beginning today, October 13. Details below. You can also currently get a free Spooky Pumpkaboo.

Original Story: Pokemon game players can bolster their collection of in-game creatures in October, when GameStop will be giving away two special Pokemon to promote some upcoming releases.

From October 13 through October 26, players can visit a GameStop store in the US to receive a card containing a code for a Shiny Gengar for use in Pokemon X/Y. This Gengar will come holding a Gengarite Mega Stone, allowing it to Mega Evolve into a Shiny Mega Gengar.

Following this, from October 27 through November 16, GameStop will be offering Diancie (the previously unobtainable Mythical Pokemon) for Pokemon X/Y. Once you’ve gotten your hands on one, you’ll be able to take it with you into Pokemon Omega Ruby or Alpha Sapphire, where you’ll then be able to get a Diancite Mega Stone that allows it to Mega Evolve into Mega Diancie.

Omega Ruby and Alpha Sapphire launch on 3DS on November 21. This giveaway is intended to not only promote their release, but that of the latest expansion to the Pokemon Trading Card Game, XY Phantom Forces.