Pocket Monsters Aka (Japan) is one of the original releases of the Pokémon series in Japan, featuring the generation 1 Pokémon. Along with Pocket Monsters Midori and Pocket Monsters Ao, it established the gameplay formula of exploration, Pokémon capture, and battles.  The 'Aka' version (meaning 'Red') likely had a different set of available Pokémon or certain storyline elements compared to the other versions, adding replayability for those who wanted a different experience.  Developed by Game Freak and published by Nintendo, its innovative mechanics helped start the Pokémon global phenomenon.

Pocket Monsters Aka (Japan)

Pocket Monsters - Pikachu (Japan)