Bowser's Chamber

''This page is covering the unused area in Super Mario 64 DS. Are you looking for the Bowser Room, a similar anomaly in the original Super Mario 64?'' Bowser's Chamber is an unused area in an early build of Super Mario 64 DS. It is a rectangular room with gray flooring, a brown lining around the perimeter of the floor, and green walls similar to that of the basement. It would contain a boss fight against Bowser using all 4 player characters. Whether or not this was going to be part of the main game, or the multiplayer mode is unknown. it was shown off in E3 2004. However, it has been reported to appear in the game due to personalization.

Description
Bowser's Chamber is typically found in a hidden area of the castle such as the Black Box, and usually drops you exactly into the room seen in the screenshots, but can drop you in an area leading up to it that's either a maze or set up similarly to a Bowser level inside of a building, usually a hidden area inside of Princess Peach's Castle or perhaps even Bowser's castle. This area usually appears similarly to the room in the photo, sometimes with no visible walls extending out to an infinite void similarly to the Princess' Secret Slide.

The boss fight with Bowser himself is usually different from regular Bowser battles, as there are no bombs in the arena like those in the 3 in-game Bowser boss fights. Notably, some have reported ways to damage them based on each of the 4 characters. Bowser can throw Bob-ombs that Yoshi has to throw back, similarly to the Bowser fight associated with the Halved Key anomaly. Mario can kick Bowser to knock them over, and then ground pound them if the kick doesn't immediately damage them. Luigi can twirl to jump on Bowser's head. If Wario has the anomalous shoulder-bash move, they can use that to damage or stun Bowser.

If Bowser is defeated, his reward varies. He can drop a special 151st Power Star, a special ending, the key to an anomalous area such as a DS equivalent of the 4th floor, or a key to unlock Waluigi in some rumors. Other reports say they don't drop anything at all, softlocking the player upon defeat or warping them back to the Castle Grounds. This is likely due to the A.I. not being able to generate the intended reward. Some of the actual rewards are likely just made up as playground rumors similarly to most playground stories related to Waluigi, but they may also be true.