MissingNo. (けつばん Ketsuban?), or MissingNO,1 is a Pokémon species found in the video games Pokémon Red and Blue. Standing for "Missing Number", MissingNo. Pokémon are used as error handlers by game developer Game Freak; they appear when the game attempts to access data for a nonexistent Pokémon species. Due to the programming of three in-game events, players can encounter MissingNo. via a glitch. The species was first documented by Nintendo in the May 1999 issue of Nintendo Power.
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