Glitch item name map distortion is a glitch in Pokémon Red, Blue, and Yellow.This glitch, discovered by TheZZAZZGlitch is caused when the name of a glitch item is so long that it will corrupt overworld data.
Specifically standing in an area with many grass sub-tiles tiles (hex:52) will force the game to display the player's name control character many times, which if (in Pokémon Red and Blue, with ####PkMnぉゥ# #ゥ #ゥC ## (0x87)) is four characters or longer can create a Glitch City.