Twenty readers were randomly selected in the original Mew lottery promotion.
Mew was a secret Pokémon hidden in Pokémon Red and Green and was not normally obtainable through ordinary gameplay. To promote the games, CoroCoro Comic announced a lottery in its May 1996 issue. Readers could submit a postcard for a chance to have Mew added to their cartridge.
The promotion created intense interest because Mew was not listed among the publicly known Pokémon. The selected winners sent in their game cartridges, allowing Mew to be uploaded to them. This unusual distribution method helped generate rumors and word of mouth around the new franchise.
Mew's National Pokédex number is 151, placing it at the end of the original roster. It is distinct from Mewtwo, which is a separate Pokémon and appears earlier in the Pokédex at number 150.