List of Mario Kart: Super Circuit pre-release and unused content
From the Super Mario Wiki
This is a list of pre-release and unused content for the game Mario Kart: Super Circuit.
The game's working title was "Mario Kart Advance" which was kept in the Japanese version. Early Nintendo Power screenshots showed that the characters had different, "super-deformed" sprites of bigger heads contrasted by smaller karts. The HUD was slightly different, though largely recognizable compared to the released version. Finally, some of the tracks had more detailed backgrounds of an almost painted-quality.
The Banana Bunch, Golden Mushroom, and Fake Item Box items were going to be in the game. The unfinished versions can be seen by using a GameShark code. The Banana Bunch has no function, the Golden Mushroom acts like a Mushroom but gives the ability to have infinite boosts even if no item is shown, and the Fake Item Box has the same function as a regular Banana.