Pokémon Crystal Version is a role-playing video game developed by Game Freak and published by Nintendo for the Game Boy Color in Japan in 2000 and internationally in 2001. The game is an enhanced edition of the 1999 titles Pokémon Gold and Silver, commonly referred to as the 'second generation' of games in the Pokémon franchise. Crystal featured several additions to the core gameplay of its predecessors, including additional story elements, the inclusion of the Battle Tower, the option to play as a male or female player character, visual enhancements to the sprite animations of Pokémon, and other minor fixes and quality of life improvements. The Japanese version of the game also showcased the capabilities of the Mobile System GB, a peripheral released to add mobile phone networking, but was not distributed outside of Japan. Released following the commercial success of Pokémon Gold and Silver, Crystal experienced similar commercial and critical acclaim, with the combined titles forming the best-selling game for the Game Boy Color and the third-best-selling game for the Game Boy family of handheld consoles. Critics praised Crystal for its additional features and improvements, whilst noting that many of the features in the non-Japanese version of the game, which lacked the Mobile System GB, were minor in nature. Retrospective assessment of Crystal has been highly positive, with several critics noting the game's introduction of a range of features that would become commonplace in later iterations of the Pokémon franchise. Source: Wikipedia (en)