Debug menu

A debug menu is a user interfaces that allows the user to change a game's internal state. The main purpose of these is for the developers to easily test various parts of the game. While most games remove access to the debug menu before release, there are some ways for a player to access one, usually by hacking.

Game Genie codes
The easiest way to access the debug menu is with the following three Game Genie Codes:

DD6C-71F9

6D6C-7199

A96C-71B9

(These codes have been verified to work on original hardware with a Game Genie.)

Once the codes are added, going to Ness's items and "Using" his ATM Card will bring up the debug menu.

Check Area Glitch
The second method can be preformed without using any Game Genie codes. The player needs to either go to the lower right section of the Threed Circus Tent, or to the upper right corner of Onett (The latter requires using the cliff glitch) and "check" those spots. If the player lucky the debug menu will open this way.

Using the Debug Menu
The debug menu in EarthBound is not fully translated, instead it displays only the first English letter for each Japanese character used. Removing Ness from the party or getting rid of the ATM card will soft lock the game. Below is a guide on how to use the debug menu: