Pokémon Red, Blue, Yellow and Green are the first Pokémon games. It takes place in the Kanto region where you play as a trainer you name. Pokémon Green was only released in Japan. In Pokémon Red, Blue and Green you choose between Squirtle, Bulbasaur and Charmander as a starter but in Pokémon Yellow you immediately get Pikachu as a starter. It's available on the original GameBoy and was rereleased on the 3DS E-Shop as a Virtual Console game in 2016. It was also remade for the GameBoy Advanced under the name FireRed and LeafGreen.