Pokémon Crystal.

About Pokémon Crystal

Pokémon Crystal Version is a role-playing video game developed by Game Freak and published by Nintendo for the Game Boy Color, released in Japan in December 2000 and internationally throughout 2001. Serving as an enhanced edition of the 1999 titles Pokémon Gold and Silver, it is the final entry in the second generation of the Pokémon game series. The game introduced several new features, including additional story elements, a Battle Tower area, the option to play as a female protagonist, animated Pokémon sprites during battles, and various minor improvements. The Japanese version of the game also utilized the capabilities of the Mobile Adapter GB, a peripheral that allowed players to trade and battle over cell phones and a paid subscription service called "Mobile System GB". These enhancements were made possible by the Game Boy Color's improved hardware, making Crystal the first game in the series to be incompatible with the original Game Boy.