Waluigi Mode

Waluigi Mode, also known as Cheater Mode or Waluigi’s Wrath Mode, is an anomalous mode found in some personalized copies of Super Mario 64 DS. This mode is unlocked by cheating in any way, such as using moon jumps or a 150-star cheat or pirating the game. The game is rearranged to be challenging even with cheats, such as moving platforms to discourage moon jumping, and notably, Waluigi has a major presence as an antagonizing figure.

General Description
Waluigi Mode is generally described as extremely difficult due to it’s nature as a punishment for cheaters. It most commonly rearranges the game to require cheats to play, or make it completely impossible or incredibly risky to use cheats. This can include making missions require cheats such as a moon jump, or making them incredibly hard to make use of due to things such as death boxes in the sky or ceilings. Enemies and hazards have also been reported to instantly kill you in this mode, and even treat it as if you just lost your last life even if you had plenty beforehand. More difficult enemies such as the Mad Piano also appear more commonly, even in places where they don't belong. 1-Ups can also take away lives, similarly to the supposed Poison Mushroom object.

Waluigi Mode also gets it’s name due to Waluigi’s heavy influence on the game if this mode is activated. Piranha Plants and Bob-ombs are more prevalent, and Piranha Plant vines appear throughout the game blocking off certain areas and making it harder to progress, similarly to the Piranha Pit, which is notably where Waluigi is unlocked in most reports. A common phenomena related to these vines most people who have encountered these vines report is that the extra door in the character selection room often attributed to Waluigi will either be covered with these vines, or have unique text that says something along the lines of “Whoever was in here left long ago.” If the player has unlocked Waluigi legitimately, the vines can appear upon being approached, or change the dialogue to be Waluigi scolding the player for trying to play as him with Bowser's dialogue jingle and Waluigi's laugh. Notably, the game over screen also reportedly alters to replace Bowser’s face with the upside-down L icon and use Waluigi’s laugh.

If one were to find an area associated with Waluigi, such as the Piranha Pit or Negative World, it would reportedly be extremely hard to navigate, likely due to the game attempting to prevent you from unlocking Waluigi in this mode. If one were to somehow unlock Waluigi and reach the final boss, Waluigi would call you out on it, with dialogue that usually goes something along the lines of: "Listen here, M- Heyyyyy, wait a minute! You can't fool me with that! Are you trying to mock me?! This place isn't big enough for the two of us! Now I REALLY want you dead!!!" before the boss fight begins, and will reportedly become extremely harder.

Waluigi’s Behavior
Waluigi himself can be seen running around the game, usually just ahead of the player and disappearing when approached when seen in the castle, or appearing in the distance watching the player. His laugh can also occasionally be heard. This has even been reported outside of Waluigi Mode, leading to this version of Waluigi being dubbed the "Waluigi Apparition". However, he is much more prevalent in levels, where he can replace Koopa the Quick as an enhanced racing opponent, potentially tied to several reports saying his Power Flower ability makes him run incredibly fast, or the famous Purple Prizes magazine scan saying you need to be “the fastest footracer in the land” to unlock him as a playable character. He will race you to the Power Star where the flag would normally be, being able to throw Bob-ombs at you to stun you and pick you up and throw you, like Big Bob-omb. If his Bob-ombs miss, they will just land on the ground and act like regular Bob-ombs. If he gets to the star first, it will never be obtainable again, and you will get the game over screen. This also happens if he appears in any other level and obtains a Power Star, as he can appear outside of Koopa the Quick missions and act similarly to the Shadow Clones from Super Mario Galaxy. Notably, if Waluigi steals 5 or more Power Stars, several say his Bob-ombs become red and deal damage to the player instead of stunning them, or even instantly killing them, and that if the Bob-ombs land they will automatically become red Bob-ombs regardless.

Final Boss Fight
In most reports of Waluigi Mode, after beating Bowser in the Sky, the player will be dropped into the Castle Grounds, where the Black Box can be found. By flying into it with the cannon, the player will appear in a throne room that is believed to be the equivalent of the 4th floor. The room itself is a large, circular room with a moon carpet in the center and a space texture on the walls, likely due to the 3rd floor walls depicting a night sky. At the edge of the room is a throne, where the player can reportedly see Waluigi appear before a cutscene takes place. Below is a transcript of this cutscene in one report:

"Alright, punk, listen up! You think you're slick, eh? Slick enough to get away with everything you do?! I know cheating when I see it, pal! I'm the best there ever was at it! Wahahahaha! ... What? You don't believe me?! Who do you think you are?! Fine, I'll just have to show you!" He holds out the stolen Power Stars. "Looking for these, loser?" A purple health bar appears where the player's usually is, starting at 9 health. The energy of all the Power Stars are stolen by Waluigi before the Power Stars are sent into the sky, giving him a new wedge of health each, before he jumps off the throne and confronts you. The boss fight against Waluigi has been described as one of the biggest challenges they have ever faced in any video game. He reportedly has all the standard abilities from before in Waluigi Mode, and even his reported special abilities upon unlocking him as a playable character, as well as his Magic Glove abilities from Wow! Waluigi. He can also reportedly throw Big Steelies, which roll around the arena and act as a stage hazard, and if they lose enough health, pick up the throne and use it as a long-range melee weapon. This form of Waluigi, dubbed Dazzling Waluigi by those who have fought him, is described as resembling a drawing of Waluigi by Hiro Takahashi, generally appearing as a more sinister version of Waluigi. Other reported changes to his design include a purple aura, red eyes, or even his clothes changing to use the texture of the Dazzling Diamonds from Wow! Waluigi, hence the name.

If one dies to Dazzling Waluigi, the game over screen reportedly stops zooming in midway, and Waluigi’s laugh becomes more intense and malicious before it zooms back out and the fight resets back to the beginning. If one were to somehow defeat them, Waluigi were to say something to the effect of “Cheaters never prosper, Mario! EXCEPT FOR ME! WAHAHAHA!” before the game crashes. The game’s save data is also usually deleted, and in extreme cases the entire game is deemed unplayable or the DS itself is bricked. Waluigi Mode is also disabled, unless the player is to use cheats again. If there was a proper ending planned, it is unknown what it would have been.

Trivia & Additional Info

 * A similar phenomenon occurs in Earthbound if the game is detected to be pirated.
 * If the player were to somehow get to Dazzling Waluigi again after already clearing Waluigi Mode, Waluigi would mock the player, saying they just HAD to cheat again, before the cutscene is skipped and the fight begins again.
 * The only information obtained on what would happen upon beating Dazzling Waluigi was obtained through data mining, as nobody to date has actually finished the boss fight. Notably, some of the dialogue obtained through this method from Waluigi includes swear words insulting the player, likely due to it not being proofread and finalized due to beating Waluigi likely being impossible. Dialogue indicating Waluigi were to talk to you upon unlocking him in a new save file after "beating" Waluigi Mode was also found, as well as hints of an even worse Waluigi Mode if one were to cheat after unlocking him. Extra dialogue scolding the player for datamining is also present, seemingly even less professional and profane than real dialogue.
 * If one were to stop cheating while playing Waluigi Mode, it would seemingly be disabled, but levels would be recolored to be Waluigi's color palette as a sign that the game still remembers that you cheated. It also would be brought back and become more intense if one were to cheat again. This would also trigger the previously mentioned dialogue of the second dialogue exchange after reaching Dazzling Waluigi a second time.