Ghastly Gulch

Ghastly Gulch is a planned course for Super Mario 64 that never got past the planning phase. It would have been a large ravine filled with Boos. There is a theory that the Personalization A.I. ruined the level before it was finished, though this is unconfirmed, and unlikely. It is speculated it would have been similar to the area known as Gusty Gulch in Paper Mario, similarly to the anomalous Mario's House level being similar to Paper Mario's Mario's House area. No more information is known, as it was only planned and any other information has been lost to time.