Childhood rivals Red and Green are charged by Professor Oak to fill out the Pokédex, a portable encyclopedia of Pokémon knowledge by traveling across the Kanto region and encountering the many species of Pokémon that roam the land. The respective plot is close to that of Pokémon Red and Green Versions, the very first games of the franchise, featuring Red as the protagonist and Blue as Red's rival.
Red arrives at Lavender Town, where ghosts have invaded Lavender Tower. It is up to Red to find the cause of the ghosts, and to rescue the missing Mr. Fuji.
Red invades the Team Rocket infested Silph Co. in order to scare off Team Rocket and prevent them from getting their hands on the Master Ball. Red then decides its time to challenge the mysterious Viridian Gym Leader.
Red makes his way through the Pokemon league and must battle the existing Pokemon League Champion in order to claim the title. Green is damaged by a mysterious Pokemon in Cerulean Cave. Red goes in to investigate this unknown Pokemon.