Author’s Note: This article first appeared on Mech Taco on February 8, 2012, as part of a series on oddities in video game history.
In Pokémon Red and Blue, if you spoke to the old man in Viridian City who shows you how to catch Pokémon, then flew to Cinnabar Island and surfed up and down the coast to the right of the Pokémon Center you would eventually encounter a Pokémon that never appeared in any Pokédex or episode of the television series. Its appearance varied depending on a number of different factors, as anything from a skeleton of an Aerodactyl or Kabutops, a black ghost, or three columns of random pixels. Although it was never intended to see the light of day, it became a popular member of the nearly six hundred fifty members of the Pokémenagerie despite not appearing anywhere in the Pokédex.
I am, of course, talking about MissingNo.
MissingNo., short for Missing Number (Pokémon #000), is a glitched Pokémon; more accurately it is less a Pokémon than a programming error triggered as the result of a combination of different factors. The game recognizes it as a dual Flying/Normal type with a high attack and extremely low defense (anything that hits it will knock it out in one hit). It has three attacks: two Water Guns and Sky Attack. When caught, it appears on your party screen as a rapidly flashing person. If you give it a Rare Candy, it will evolve into a Kangaskahn.
Because it is technically a glitch, catching it and keeping it in your party causes a number of different unwanted side effects. The effects of catching MissingNo. include making your Pokémon appear glitchy in battle and making random sprites appear on your party and Hall of Fame screens. If caught at level zero, MissingNo. (and similar glitched Pokémon such as ‘M) can also corrupt your save file, forcing you to erase your data.
So why bother with MissingNo. at all? In spite of all the nasty side effects, there are some significant benefits to hunting down the legendary glitch Pokémon. For one, MissingNo. is not the only Pokémon you will encounter after your date with the Old Man; you will also run into Pokémon with extremely high levels, ranging anywhere from 130 to the two hundreds. The types of superpowered Pokémon you encounter is determined by your trainer’s name, and there are guides that show you ways of guaranteeing certain Pokémon like Mewtwo. For my copy of Pokémon Red, I encountered Snorlax and Golbat. These Pokémon are safe to catch and your game will suffer no ill effects from having them. After one battle they will revert to level 100.
More important, after you complete a battle with MissingNo. (either by defeating or catching it) you will gain 156 of whatever item you have in the sixth slot of your inventory. This became a quick and easy way to get large numbers of useful items, such as Master Balls and Rare Candies.
Over the years MissingNo. became part of Pokémon fan culture. People have made Pokémon cards in its likeness and it has appeared in fan art and web comics. Moreover, its existence led players to search for more glitches in the games which has yielded interesting results, including a glitch allows you to legitimately find Mew without a GameShark or Game Genie. For Pokémon trainers of a certain age, MissingNo. became as much a part of Pokémon as Pikachu.
MissingNo. is the most famous of the glitch Pokémon, but he’s far from the only one. Here are a few other noteworthy ones:
h Poke – Another glitch from RBY. Catching it will crash your game unless you have a Gengar in your Pokédex . One of its attacks is HM02 (not Fly, “HM 02”), a mighty move that delivers a one-hit knockout and restores health for h Poke.
?????????? – A glitch Pokémon from Ruby/Sapphire/Emerald that looks like a question mark in a circle. While it can be caught, it can only level up using Rare Candies. Also if the player tries to view ?????????’s Summary, the game will freeze.