Alternate Castles

Appearing rarely in personalised copies, the Alternative Castle is an anomaly which causes the appearance of Princess Peach's Castle to change drastically. The music apparently is a 'slightly-off' version of the regular castle theme.

Geography
The layout of the Alternative Castle shares multiple graphics from the regular castle, yet often borrowing scrapped or unused graphics from earlier betas. The castle is separated into four areas: the Hub, the Upper Area, the Garden and the Dungeon.

The Hub
Upon entering the castle via the outside door, Mario lands in the Hub. The Hub consists of multiple branching hallways leading to paintings and a staircase leading to the Upper Area and the Basement. The graphic used for the walls in the Hub is the Third Floor's Starry Sky graphic. The paintings in the Hub require no stars to enter.

The Upper Area
At the top of the main staircase is the Upper Area, consisting of multiple bookshelves, in which Boos roam. Inbetween the bookshelves are red coins, which give Mario a secret star. An entrance to Bowser in the Sky lies at the end of the library of bookshelves, which is the only level in the Alternative Castle which is also in the regular castle. The Upper Area uses the beta castle wall textures.

The Garden
In one of the hallways in the Upper Hub is a pipe leading to The Garden. The Garden resembles the Castle Courtyard with some slight alterations: there are the unused dancing flowers scattered randomly, the Eternal Star uses a metallic texture and sometimes Goombas appear.

The Dungeon
The Dungeon is a small area accessed by ground-pounding into a specific spot of the carpet in The Hub, in which Mario will fall through a deep hole into The Dungeon's loading zone. The Dungeon is a labyrinth with multiple different rooms which, according to some reports, sometimes 'move around' and trap players in rooms. The walls use the Castle Basement wall texture.