In 2021, a speedrunner working with a group effort to decompile the game uncovered a cheat code that can turn a 0% save file into a 100% save file, likely used by the game's developers for debug purposes. To use the code, you must first plug in two controllers, turn on the game and create a new save on File 3. It does not matter if there is save data or not on File 1, but File 2 must have no save data. Then reset the game and, using the second controller, hold L when the Nintendo & HAL Laboratory logos appear and press C-Up/C-Up/R/C-Right/C-Left/Start. The 1-Up sound effect will play if done successfully, and File 3 will now hold a 100% save file.

This code can be executed on every release of the game except for the Wii Virtual Console release due to the lack of C-Button mapping for that version.