Pokémon Blue replaced Pokémon Green in the international release of the original games.
Japan received Pocket Monsters Red and Green in 1996. For markets outside Japan, Nintendo released Pokémon Red Version and Blue Version instead, making Red and Blue the pairing most familiar to international players.
The games were not identical in their available Pokémon, which preserved the series' trading-centered design. Players could connect two Game Boy systems and exchange species unavailable in their own version.
Pokémon Green was not released internationally as the original counterpart. Later remakes, including Pokémon FireRed and LeafGreen, restored the Green name in a different context by referencing the Japanese originals while using updated Game Boy Advance technology.