SM64: The Show

Super Mario 64: The Show (alternate titles include: SM64: The Show, Super Mario 64: The Quest to Save Peach) was a planned expansion to Super Mario 64 planned to be released on the Nintendo 64DD. It was going to allow players to view their playthrough in the form of a cartoon, similar to other Mario cartoons such as the Super Mario Bros. Super Show.

Functionality
According to early design documents, the player would have to insert Super Mario 64 into the top of the N64, before inserting SM64: The Show into the Disk Drive (similarly to the F-Zero X Expansion Kit). Upon booting up Super Mario 64, the disk would scan the player's save data, and would create a personalized cartoon adaptation of the user's playthrough so far, which could be viewed in a newly-unlocked cinema area inside Peach's Castle. If the player were to have done co-op with a friend at one point, Luigi could appear in the episode. If a player were to encounter anomalies such as Enemy Discoloring, The Wario Apparition, and the Fourth Floor, said anomalies would have a 50% chance of appearing in the animation. Disputes on why this is the case commonly occur to this day.

Appearance
The Cinema area would be filled with black walls with dim lights, as well as blue carpet floors with star patterns. Upon entering a viewing room, the player would select options for the cartoon's appearance. The options would be as follows: 2D or 3D, how many minutes per episode, music to use in the episode. The gameplay would soon switch to a cartoon episode, which players could exit by pressing the B button.

Episode Titles
The pitch document details a few episode titles from very early testing. The episode titles are as follows: The Adventure Begins, Climbing the Cold, Cold Crevasse, What a Discovery! A Secret Slide!, Luigi Saves the Day, Adventure's End.

Theories
Many theorise that SM64: The Show was an early test by Nintendo at generating CGI and 2D animation, possibly to use for future movies or cartoons. Many also theorise that using Randnet, the expansion would've been able to connect to MariOS 64, allowing users to upload their episodes to be viewed by others.