Alternate Castles

Alternate Castles are anomalous hub worlds created by the Personalization A.I. in extremely personalized copies of Super Mario 64. They most often replace Princess Peach’s Castle, though may sometimes appear in tandem with it, often to the detriment of the original castle’s size. As one would expect, these anomalies are extremely rare, and nearly impossible to encounter on a first playthrough or in a lightly personalized copy. They can range from retextures & rearrangements of the original castle, complete redesigns of the castle, or even entirely new locations created from scratch through processes such as Dynamic Level Arrangement.

General Description
All Alternate Castles have certain similarities. As one would expect, they contain several levels, usually both full courses and full levels, though sometimes only one or the other. They tend to contain at least two major areas, though enough to rival the original castle have been documented. As one would expect, they are treated as a separate zone from the castle, hence their designation, though they do not have to actually be a castle to qualify.

Alternate Castles are rare anomalies, and players typically have to play through the game to completion at least once before one will appear. Despite large variation between reports, there are some consistent ways to trigger one’s appearance if the Personalization A.I. believes one should be created:


 * Beginning a new save file after one has already been completed, either as one normally would or by selecting something such as an Alternate Campaign, which increases the chance of an Alternate Castle. Worth noting that this is usually accompanied by the Alternate Peach Letter Anomaly and an Unintended Playable Character of some kind, most often Luigi.
 * Completing an Alternate Ending, such as the Bad Ending, which would result in an Alternate Castle appearing in place of the original castle.
 * Triggering a Stage 4 or Stage 5 Sudden Restructuring, which would replace the castle, or chunks of it, with a new hub world. This method of triggering an Alternate Castle usually brings Mass Game Retheming and similar anomalies along with it.

A save file with an Alternate Castle can usually be reverted back to Princess Peach’s Castle by deleting the save and recreating it as one would in an “un-personalized” copy, thus resetting the hub world back to normal, though this does not work in all cases where the anomaly is encountered.

Alternatively, some reports of Alternate Castles report that they can be accessed alongside Princess Peach’s Castle, usually via a special warp such as a hidden painting or shooting out of the Castle Grounds with the 120-star cannon. The main castle is usually reduced in size to reallocate the cartridge’s storage, and the “Second Castle” tends to be small, usually only consisting of 1 or 2 floors worth of levels, either with levels moved from the main castle or new levels to fit the new environment.

Alternate Castles & their levels also tend to come with instability of some kind, such as glitched collision & geometry, Active Geometric Aberration, game crashing, inaccessible locations & collectibles, and similar inconveniences, likely due to the intense workload required for redesigning the entire game. As such, several reports have ended before the player completed the Alternate Castle, leading to gaps in information.

Documented Instances
''This list only consists of several Alternate Castles that have been reported enough to assemble a description of their attributes. Several more have been reported, and those listed here are likely to deviate vastly from copy to copy. These descriptions have also been written assuming these areas have replaced Princess Peach’s Castle instead of appearing alongside it, and as such would have different properties in such a scenario.''

Princess Daisy’s Castle
The term “Princess Daisy’s Castle” refers to any Alternate Castle where the entire castle is redesigned enough to be considered an entirely distinct location, and not just a castle themed around Sarasaland & Princess Daisy, though such a thing is also commonly documented. These castles are worth note, as they commonly contain floors strikingly similar to anomalous floors documented in the regular castle such as the Fourth Floor and Floor 2B, locations resembling earlier versions of Princess Peach’s Castle from older builds of the game such as the one seen in Spaceworld ‘95, and also levels that appear to resemble the descriptions of the unused courses found in the level list, implying a connection of some kind. This Alternate Castle is also the one most commonly reported to contain the Castle Living Space Anomaly, as it is more often depicted as actually being someone’s home.

Princess Daisy is not the only character for an Alternate Castle of this description to be themed around, though she is the most common, hence the designation. Other characters include Mario, likely as a reference to his castle in Mario Land 2, “The King”, either Toadsworth, a similar character, or the one seen in the Throne Room, Pauline from the Donkey Kong games, or even an entirely new princess seemingly created by the Personalization A.I.

Bowser’s Castle
Bowser’s Castle, as one would expect, is a dark, gloomy castle with a stark contrast in design to Princess Peach’s Castle and a focus on fire & “spooky”-themed locations, such as the Castle Dungeon, Big Boo’s Forest, Smoky, Smoky Spires & Hollow Horror Halls. The levels found in Bowser’s Castle are generally described as being much harder than the ones one would encounter in the normal castle, and as such commonly only appears to players who are able to take on the challenge. Its other defining factor is its appearance after a Bad Ending, and being one of the only locations where one can trigger a Savior Ending. After the Savior Ending, players usually report being sent back to the regular castle and being unable to return to Bowser’s Castle.

Bowser’s Castles have sometimes been classified in reports as Princess Daisy’s Castles, as they have several similar characteristics, though a distinction is made here due to the significant differences in reports & its frequency.

His Domain
Main Article: His Domain

His Domain, like Bowser’s Castle, is commonly reported after completing a Bad Ending, replacing Princess Peach’s Castle until it is completed. It is described as a labyrinth-esque base of operations created by Bowser after demolishing the castle, with several levels mirroring those seen on the first floor of Princess Peach’s Castle. It is also one of the shorter Alternate Castles reported, usually only containing 1 or 2 floors worth of content, typically corresponding to the first floor & basement of Princess Peach’s Castle. Unlike Bowser’s Castle, players report that after the Savior Ending, they either stay in His Domain or go to a Princess Daisy’s Castle, likely due to the fact that in His Domain’s continuity the original castle is often destroyed and thus cannot be returned to.

The Sunken Castle
Main Article: The Sunken Castle

The third Alternate Castle tied to a Bad Ending of some kind, the Sunken Castle is commonly reported to be a replacement for Princess Peach’s Castle found after a Bad Ending, and is a destroyed & submerged version of the castle, sometimes upside-down. Like His Domain, it also contains levels mirroring the main castle, but they typically take on darker tones, such as Whomp’s Fortress being replaced with Ruins, implying some connection between the destruction of the castle and the destruction of the painting worlds. Like His Domain, the Sunken Castle’s Savior Ending usually does not return the player to the original castle, instead leading to yet another Alternate Castle.

Toad Town
Main Article: Toad Town

Toad Town is a reported area that most often appears as a small hub world area comparable in size to the third floor, though some have reported it can appear in the role of an Alternate Castle. As you would expect, it is a group of houses & buildings located outside the Castle Grounds, with Toads and other NPCs mulling about, When it acts as a hub world of some kind, the buildings tend to contain paintings or other warps that will take you to it's levels. The levels tend to be themed around Toads, and archetypal locales matching the descriptions of locations from Paper Mario 64, in which Toad Town is also a prominent landmark.

Mario’s House
Main Article: Mario’s House

Mario’s House, similarly to Toad Town, has sometimes been reported as a unique hub world separate from Princess Peach’s Castle instead of the small location it is most commonly described as. As one would expect, the area is described as a grassy plain with a house belonging to Mario & Luigi in the center as the main landmark. A handful of reports claim this version of Mario’s House contains areas comparable to those seen in Mario’s Adventure, implying that the A.I. was trying to “recreate” the locales seen in that game. A similar trend in reports also exists for areas resembling Paper Mario 64’s, much like Toad Town, as this area is also present in the game.

Theorizing
Alternate Castles, like Sudden Restructuring, appear to be a drastic attempt from the Personalization A.I. to keep the player engaged and continue playing even after the game has been cleared, typically by completely overriding the original castle to create a whole new experience. However, this is not without its flaws, both in gameplay as described above, and discovery, as several players would beat the game once and not consider the possibility of an Alternate Castle.

Alternatively, Alternate Castles may be an attempt to recreate castles from earlier versions of the game. Some have theorized that this means literal multiple castles were planned in earlier builds of the game, though this is unlikely. Instead, most believe they are remnants of earlier designs of the castle, redesigned and reshaped by the A.I. to fit the final build of the game.