List of Super Mario Kart pre-release and unused content

This is a list of pre-release and unused content for the game Super Mario Kart.

Early iteration
The game was initially developed as an original IP and starred a "guy in overalls". The game was retooled as a Super Mario spinoff after the development team replaced the player character's sprite with Mario and decided that they liked the look of the game better that way.

Prototype cartridge
A user on the Digitpress forum bought a prototype cartridge and showcased its differences in a thread. It is very similar to a leaked prototype dated May 18, 1992.

Visuals

 * The Cheep Cheep sprite is upside-down.
 * The cup selection screen lacks a border.
 * The X on Lakitu's flag when the player drives the wrong way is not present.

Sound

 * Vanilla Lake 1 has a different theme, which does not appear in the final build.
 * During the Rankings screen after completing a race, Donkey Kong Jr.'s theme is different than the final version.
 * The Bowser's Castle theme is played in Rainbow Road.
 * Most sound effects are different or have a different pitch.
 * Some themes have slightly different instrumentation and rhythms from the final version.

Content

 * The prototype has animations when ranking 2nd or 3rd place in a championship, something which does not happen in the final game. Scoring 2nd shows a Super Koopa looping over the podium and then getting hit by the winner's champagne cork, while the 3rd place animation has a group of Koopa Paratroopas flying over the podium, the last of which is also hit by the cork.
 * The 150cc mode is not present.
 * The "Replay" feature for Time Trial mode is absent.
 * Battle Course 3 is set in Choco Island and has a different layout.
 * Rainbow Road is narrower.
 * The player cannot drop the Green Shell item or throw the Banana Peel.

April 13, 1992 Prototype build
On July 24th, 2020, a prototype build for Super Mario Kart dated April 13, 1992 was leaked and many differences can be found between the prototype and the final game.

Visuals

 * The X on Lakitu's flag when the player drives the wrong way is not present.

Sound

 * The title screen and Vanilla Lake have different themes, both of which do not appear in the final build.
 * The Donut Plains theme has a different pitch compared to the final build.
 * The Koopa Beach theme is shared with the Choco Island courses.
 * The theme used for battle courses in the final build is played in Mario Circuit, Ghost Valley, and Bowser's Castle courses.
 * Battle courses use the themes of the respective courses they are based off of instead of the normal theme used for battle courses in the final build.
 * The title screen theme is played during the ranking screen at the end of a championship.
 * During the Rankings screen after completing a race, Donkey Kong Jr.'s theme is different than the final version.
 * Some themes have slightly different instrumentation and rhythms from the final version.

Content

 * The 150cc mode is not present.
 * Many courses, including battle courses, have different layouts compared to the final build.
 * The drifting mechanics work differently in this build, as there is no jumping before drifting.
 * The course orders of various cups are different.
 * A Choco Island 3 course can be found in the Special Cup instead of Rainbow Road.
 * Battle Course 1 in this build is the Battle Course 4 of the final game, set in Donut Plains.
 * Battle Course 2 in this build is the Battle Course 3 of the final game and has more ice blocks.
 * Battle Course 4 in this build is the Battle Course 2 of the final game.
 * Battle Course 3 is set in Choco Island and has a different layout.
 * Vanilla Lake 1 does not load in and crashes the game.
 * The unused 2nd and 3rd championship animations are swapped. The Super Koopa does not spin around when hit and the Koopa Paratroopa simply walks away rather than bouncing. The animations are also slower.
 * The championship messages are not present, instead appearing as a series of dark red ones.
 * An unused driver appears in the game's files. The driver looks like a generic racecar driver. Unused sprites show the character in both a normal kart and what appears to be a bumper car.