Super Mario 64 2

Super Mario 64 2 (alternatively Super Mario 64 II or Super Mario 128) was the tentative title for a Mario game in development that served as the direct sequel to Super Mario 64, intended for release in 1999. It was going to be for the Nintendo 64DD, but was canceled early in production due to lack of progress and the commercial failure of the 64DD add-on. Only one demo level was ever made but was never publicly revealed. It is also possible that Super Mario Sunshine, Super Mario Galaxy, or Super Mario Galaxy 2 could have elements salvaged from the development of Super Mario 64 2, according to Nintendo during an E3 event. Other characters and concepts discarded from the first game were set to return in this game, such as Luigi and a rideable Yoshi. The game was planned to feature at least two players – in fact, Shigeru Miyamoto's first playable demo level was multiplayer. It is also unknown what power-ups, if any, were going to appear in the game.

It is speculated by fans that the unreleased Nintendo 64DD port of the original Super Mario 64, titled Super Mario 64: Disk Ban, may be related to the game.

Another potential sequel would have been Super Mario 128, but that game was developed in private before being ultimately canceled.