Super Mario Advance 4: Super Mario Bros. 3 features e-Reader compatibility, in that it can link up to a second Game Boy Advance with an e-Reader. Upon scanning in one of three types of cards, something will then be triggered in the game. This feature is normally absent in the European version of the game but can be enabled using a cheat device. Power-Up Cards: When one of these is scanned, it will upload an item (or a set of items) into either Mario or Luigi's inventory. There is no limit as to how many times an item card can be used. A variant type of Power-Up Cards are Switch Cards, which will trigger something in the game upon being scanned. Demo Cards: Plays a movie of either Mario speed-running through a level, collecting enough coins in a certain level to trigger a White Mushroom House, or racking up numerous 1-Up Mushrooms via a special trick. Level Cards: Uploads a brand new level into the game, which can be played in World-e. Note that only 32 levels can be saved on the game at a time, but the listing of levels is endless