Green was originally seen in various concept artwork for the original games, Red & Green, and her design was then used in the Pokémon Adventures Manga and then adapted into the player character Leaf for FireRed & LeafGreen. Pokémon Let's Go, Pikachu! & Let's Go, Eevee! marks Green's first ever appearance in the video games.
|Encounter 1: Cerulean Cave|
Location: Cerulean Cave
After defeating the Elite Four, you will get informed by your Rival of a mysterious Pokémon in Cerulean Cave. When you go there, he will mention about both him and a girl wanting to go find Mewtwo. Capture Mewtwo and your rival will tell you that the girl is still inside the cave. Go all the way back to where Mewtwo was and you'll find Green. When you speak to her, she'll throw a Poké Ball at you thinking that you're a Pokémon as it's dark. She'll soon apologise and then will challenge you to a battle after seeing you had obtained Mewtwo. She uses Mega Blastoise.
When you defeat her, she will offer for you to join her, with Mewtwo, as her Pokémon and will continue to throw Poké Balls at you, leaving 5 on the floor for you to collect.
|Encounter 2: Cerulean City|
Location: Cerulean City
After defeating her in Cerulean Cave, the next day Green will start appearing by the bike shop in Cerulean City. After defeating the Elite Four again, she will challenge you to a rematch.