 Brawl is unusually moddable for a console game, due to the "Smash Stack" exploit found within the game's built-in stage builder when loading stages from an SD card. Rather than stage data, a specialized program can be inserted onto the SD card that renders the builder unusable while present, but allows loading of fan-made patches from the card on top of the game's on-disc data. These patches range from simple character skins and balance adjustments to more complex modifications such as whole additional characters and extra stages more complex than the internal stage builder allows.
