After being in development for six years, an incredibly long cycle at the time, the original Pokémon Game Boy games were finally ready. They were packed so full of story, characters, and features that the storage cartridges they’d be shipped on were filled to the brim.
Just before the release, however, the debug features only used by developers were removed, freeing up 300 bytes, a minuscule amount of space. Shigeki Morimoto, one of the programmers, decided to have some fun: On top of the scoped 150 pocket monsters in the game, he snuck in one more.
The name of that Pokémon was “Mew.” It received its own entry in the Pokédex, the in-game encyclopedia, number, and unique set of attacks. The only catch? You couldn’t actually catch it—pun intended. So Morimoto thought, at least.
There was no place in the game where you could trigger an encounter with Mew, but within weeks of the game’s release, players somehow did. No game is perfect, and this one, too, had bugs. Occasionally, those bugs made Mew appear, and it caused immense speculation.
The creators were thankful for the buzz: They had released the game in February because they’d missed the usual October release window the year before. It was a bad time to put out games, and Pokémon sold accordingly. After such a long time to market, this was not what they had hoped for.
With rumors around a 151st Pokémon hiding somewhere inside the code of the game, Mew, the mythical Pokémon, literally became an urban myth. Players developed all kinds of theories as to why it was there, which patterns one had to follow to catch it, and whether or not Nintendo had intended for all of this to happen.
Sensing a PR disaster in the making, Nintendo decided to let the cat—Mew is named after the sound felines make—out of the bag. They held an official “Legendary Pokémon Offer” event where, after sending in their game cartridges, 20 players would receive a proper, sanctioned copy of Mew in their games. The promotion blew away anyone’s expectations. Some 78,000 people applied.
Tsunekazu Ishihara, the founder of The Pokémon Company, recalls in an interview: “The monthly sales we’d had up to then began to be equalled by weekly sales, before increasing to become three then four times larger.” Even Satoru Iwata, the late president of Nintendo, admitted: “I remember feeling that I’d never really witnessed a game selling like that before.”
Even though it took over three years for the games to make it to Germany, after my friends and I received our copies while in third grade, the rumors around Mew were alive and kicking. Tongue-in-cheek, its Pokédex entry was updated for these international versions: “So rare that it is still said to be a mirage by many experts. Only a few people have seen it worldwide.”
To this day, the lore around Mew drives people to Pokémon. Videos are still being made about its origins, odd traits, and the many ways to obtain it through various glitches discovered over the years. Chances are, without Mew, Pokémon would not be what is today: the highest-grossing media franchise in the world. If the original game sales hadn’t eventually picked up, Pokémon might have stayed a niche game exclusive to Japan. But they did, and it was all thanks to the rumors caused by a prank from an early team member.
Morimoto’s move feels like the kind of joke no one makes anymore. It was bold, but a good number of team members was still in on it. And Mew would have been revealed to the public regardless, at the latest with the release of the second generation of Pokémon games. The gag was gutsy but not disrespectful.
Today’s culture may no longer feel as receptive, but have faith: There’s always room for a practical joke. All we need to do is create that room in our minds and hearts—and we should. After all, you never know just how practical your joke might become down the line.
