Talk:Missingno Murder/@comment-70.123.134.74-20151112024255/@comment-26480939-20170704194759

Basically what A FANDOM user (Dec. 8, 2015) said. Missingno. is a failsafe put in place to prevent game crashes from happening when the game reads something other than Pokémon encounter data as exactly that. Missingno. happens because the game reads your character's name and uses the 3rd, 5th, and 7th letter spaces and sometimes will generate a Missingno, or a very high-level ordinary Pokémon, sometimes even Mewtwo or the starters. And the 'fact' that Missingno is basically a portmanteau of 'missing' and 'number' is fairly well-known in the older sections of the fanbase. Basically, the most popular method involves the Old Man's Pokémon catching tutorial temporarily setting your name to 'OLD MAN' and putting your actual selected at start name in another location, namely, Pokémon encounter data, as that is under normal circumstances supposed to be blank when in a town. As the Pokémon encounter data is normally overwritten when moving to a new location by walking (but not when using Fly, for some strange reason), this wouldn't be a problem. Since the Old Man glitch involves flying to Cinnabar, where the eastern coast of the island doesn't have any encounter data set for it, your character name stays in the encounter data and thus triggers Missingno. to appear if you have any of the following characters in the 3rd, 5th, or 7th (and if the name is long enough, 9th and 11th characters as well): G, H, M, S, :, ], a, b, c, m, o, p, v, w, x, y, null character, end of name marker, or space.

tl;dr: Check the following pages for more specifics on how this works:

[https://bulbapedia.bulbagarden.net/wiki/MissingNo. MissingNo.-Bulbapedia]

Old man glitch-Bulbapedia