Princess Peach's Castle/Goomba Courtyard

The Goomba Courtyard is an anomalous version of the Castle Courtyard found in some personalized copies of Super Mario 64. It will appear in place of the Castle Courtyard, though it may need to be accessed through alternate methods, such as a path in the Castle Grounds. The Goomba Courtyard appears similar to the Castle Courtyard, except for an occasional lack of trees, Goombas consistently appearing, most commonly in place of the Boos though occasionally alongside them, and usually minor alterations to the geometry of the courtyard.

The Goomba Courtyard has been reported to very uncommonly have enough Goombas to award a 121st Star, though this is unconfirmed and very rare. However, a castle secret star is common in this form of the Castle Courtyard. The star can take the form of 8 red coins dropped by the Boos, similarly to the star in Super Mario 64 DS, or breaking a box containing a star.

Notably, manifestations of the anomalous form of the Battle Fort level have been reported to be more common in the Goomba Courtyard. Another oddity is that most people report the cage leading to Big Boo's Haunt not being present, and the level is accessed through other means, or removed entirely. It is currently unknown why these anomalies are more common in the Goomba Courtyard, though it is potentially due to it's anomalous nature itself.