MissingNo.

Developed by Game Freak and published by Nintendo, the Pokémon series began in Japan in 1996. The player assumes the role of a Pokémon Trainer whose goal is to capture and train creatures called Pokémon. Players use the creatures' special abilities to combat other Pokémon,[1][2] and certain abilities also grant new ways to navigate the game's world, such as instantaneous travel between two areas.[3]

Nintendo of America first documented the events that cause MissingNo. to appear in North American copies of Pokémon Red and Blue in the May 1999 issue of Nintendo Power, with a warning that "any contact with it (even if you don't catch it) could easily erase your game file or disrupt your graphics".[4] The glitch is the result of a succession of events: first, players watch an in-game tutorial for Pokémon capture. The player then uses a Pokémon with the Fly move to reach the game's Cinnabar Island location, and then uses a Pokémon with the Surf move to travel up and down the eastern shore of the island until a MissingNo. appears.[5] Despite Nintendo's statements on the glitch, as of 2016 it has not been removed from re-releases of the games, such as on Nintendo's virtual console service.[6]

The eastern shore of Cinnabar Island, a key component for activating the glitch.

Encountering a MissingNo. Pokémon is the result of a sequence of unintended events. The first is the game's random battle encounter system; each area assigns values to Pokémon in a data buffer, which the game accesses for the player's encounters with wild Pokémon. However, the locations Cinnabar Island and the Seafoam Islands do not assign data to this buffer—the information from the previously visited area is used instead. The second factor is the in-game tutorial, which temporarily stores the player's name in the data buffer. This causes the game to access the hexadecimal values of the player's name for Pokémon encounters at Cinnabar and Seafoam Islands, triggering a battle with a nonexistent Pokémon.[5]

As with any wild Pokémon, players may flee from, fight, or capture MissingNo.[7] After an encounter with MissingNo., the quantity of the sixth item in the player's inventory is increased by 128 and the game's Hall of Fame Pokémon gallery becomes permanently glitched.[8] Temporary graphical glitches may also occur, which can be removed by viewing the statistics page for another non-glitched Pokémon or resetting the console.[7] A captured MissingNo. is a fully functional Pokémon and appears in the game's Pokémon index as number 000. All MissingNo. possess consistent abilities, types, statistics, and sounds. The Pokémon commonly appears as a scrambled "d"-shape, but certain encounter values cause it to appear as one of three sprites not used by other Pokémon.[7]

Calling MissingNo. a "programming quirk", Nintendo warned against encountering it, saying players could possibly have to restart the game from the beginning to remove the graphical glitches.[9][4][10] Despite Nintendo's warning, information on how to encounter MissingNo. was printed in several magazines and player's guides due to its perceived positive effect.[10][11][12] Certain players attempted to sell tips on capturing MissingNo. for up to $200.[13] Despite it not being an intentional part of the game, in 2009, IGN included MissingNo. in its list of the top video game Easter eggs, citing its usefulness in replicating the game's rarer items.[14] IGN stated in a related article, "It really says something about Pokémon fans that they took what is a potentially game-ruining glitch and used it as a shortcut to level up their Pokémon",[5] and later called it an "unforgettable" glitch that helped push the original games to "gaming super stardom".[15] The book 100 Greatest Video Game Characters describes MissingNo. as an example of a player-produced character and counterplay, adding, "as a cultural artifact, MissingNo[.] celebrates the creativity of deviant and subversive forms of play".[16]

Players' reactions to MissingNo. have been the subject of sociological studies. Sociologist William Sims Bainbridge stated that Game Freak created "one of the most popular glitches ever in game history", and cited its creative usage by players.[17] His daughter and fellow sociologist Wilma Bainbridge attributed widespread interest in glitch hunting and speedrunning in video games.[18] University of Portsmouth professor Lincoln Geraghty examined fan theories on the glitch, describing it as "an established work of fanon [fan canon]".[19] He further elaborated in an Ars Technica article "fans’ desire to incorporate MissingNo[.] into the Pokémon world stems partly from a hope that the glitch may have been deliberate", as well as to compensate for the glitch's lack of backstory within Pokémon canon.[18] In the book Pikachu's Global Adventure: The Rise and Fall of Pokémon, professor of education Julian Sefton-Green noticed that in his study of his son's reaction to MissingNo.'s usage as a cheat, the child's outlook towards the game was altered drastically, and added that the presence of such elements as a result broke the illusion of the game as an enclosed world and reminded him that "at heart, it is a computer program".[20] The book Playing with Videogames contains an in-depth study of MissingNo., which details players' curiosity when encountering the Pokémon. It describes their tendency to compare notes on its appearance, and to give assessment and critique to each other's findings.[21] The book states that, in their attempts to interpret MissingNo. as part of the series' narrative through fan art and fiction, Pokémon communities celebrated the game's imperfections and tried to imprint themselves on its canon.[21] The author described these circumstances as unique to MissingNo. and called its popularity an unusual case.[8]

• MissingNo. on Bulbapedia