Blasting Bullet Factory

Blasting Bullet Factory is an anomalous level found in some personalized copies of Super Mario 64, believed to be an early version of Tick Tock Clock. It is often described as a very difficult factory level with lava and various mechanical hazards. It can reportedly be found in place of Tick Tock Clock, though has been reported to appear elsewhere. It notably has a sub-area that can reportedly hold the Yellow Cap Switch in some copies.

Geography
Blasting Bullet Factory is typically described as being a tall cylindrical level like Tick Tock Clock with several paths branching outwards, typically with lava, several unique hazards and enemies for each segment. The level's paths can also reportedly spin, though this is rare. Some notable rooms include a hallway with a conveyor belt covered in gas similar to that of Hazy Maze Cave, an office room, and a room with a cannon allowing the player to continue upwards through the level. Many of the assets in Blasting Bullet Factory are similar to or reused in Tick Tock Clock. This level's enemies include Bob-ombs, Chuckyas, Heave-Hos, Bullet Bills as the name and painting suggest, and even Motos.

Sub-Area
There is a supposed sub-area typically found in the office of Blasting Bullet Factory which is rather inconsistent in design. It is usually described as a slide similar to those seen in the main game, or a water-themed level similar to the Secret Aquarium, or even a mixture of both. The main goal is typically to reach the end of the area, collect 8 red coins or drain the water out of the level if it is present. The most notable aspect of this area is that some have reported there being a Yellow Cap Switch at the end, though what it unlocks upon being pressed is inconsistent, with some even saying it appears pressed as if one had hacked it into the game, likely due to the A.I. failing to complete it. However, this is relatively uncommon compared to other parts of Blasting Bullet Factory and should not be thought of as the only way of obtaining the Yellow Cap Switch.

Missions
This level usually has similar missions to that of Tick Tock Clock, alongside a mission for completing the sub-area. However, other stars are also commonly reported, such as fighting a Chuckya or Motos, either as an enemy or a mini-boss/boss encounter, getting through the conveyor covered in gas, simply finding one in the office area or a similar room, using the Koopa shell to enter a previously inaccessible area likely due to their association with the Yellow Cap Switch, or even somehow "chasing" a star, either due to it being on a conveyor, having a unique behavior or being carried by an enemy such as a Money Bag.

Theorizing
Most reports claim that Blasting Bullet Factory appears to be very intact, functional and completed, leading many to believe it was cut rather late into development. This was likely due to it's difficulty, or the removal of the Yellow Cap Switch and/or Motos which are notable aspects of this level. It was likely recycled into Tick Tock Clock in order for there to be 15 courses in the game.

It is worth noting that this level could have been the supposed Motos Factory, as Motos are often reported alongside it and it resembles a factory. Alternatively, it could have been a second lava level, judging from it's usage of lava and the same painting frame as the Lethal Lava Land one, or an analogue to Hazy Maze Cave, as some missions reportedly require the Koopa shell, both level designs being boxed in, and both having a cap switch, though this is debated as the Yellow Cap Switch could have held another power-up or have been added to the level by the Personalization A.I.