Buy N Sell

Buy N Sell is the name given by the community to a short, horror themed Super Mario 64 ROM-hack created by HandsomeChris. This ROM hack can be bought from the website ¨supermario64buynsell.com¨, hence the name, in cartridge form. Upon discovery, this ROM hack faced heavy criticism for its story-line and imagery, though it has been praised by anomaly researchers due to it being the first ROM hack to involve the PAI.

This ROM hack is the first hack of Super Mario 64 that affects the PAI. The hack is actually generated by the PAI using assets inserted into the game by the creator of the ROM hack. This makes it notable to the MIPS Hole Wiki.

Acquirement
These cartridges can be acquired from the website "super64mariobuynsell.com", which was first discovered in a series of poorly made strange YouTube advertisements that advertised mint condition cartridges of Super Mario 64. The only feature of this website is a page where you can order a cartridge of Super Mario 64 listed as "Mario" on the website. The website states that it was created by HandsomeChris. These cartridges have only ever been shipped to users within the United States. The way that users have ordered these cartridges is by sending an envelope with 10$ inside to a PO box in Utah. Once the seller has received the money, they will email the buyer with a conformation email of the cartridge being sent. Soon, a package will be sent by the USPS containing a single N64 cartridge, which usually has no sticker and the words "MARIO" written in pink permanent marker where the sticker would be, but some have the Mario 64 sticker still there.

Starting the game:

 * When you attempt to stretch out any of the Mario head's features on the title screen, loud static sounds start playing and the head starts deforming and twisting, preventing you from manipulating Mario's features, though not starting the game. In addition to these static sounds, random sound effects from the base game will start playing at random intervals, and a track of a faint Japanese voice stammering and whimpering. Pressing start stops these anomalies and goes to the file select.
 * When starting the game, you are placed in front of the door in Princess Peach's castle instead of having the cutscene play,

Princess Peach's Castle

 * None of Bowser's text-boxes appear upon entering the castle.
 * The toad near the wall on the first floor also doesn't appear.
 * No music plays in the castle or in the castle grounds. In the castle, the only door that can be opened is the Bob-Omb battlefield door, the door to the basement is locked, and the wing cap stage cannot be accessed.

Bob-Omb Battlefield

 * The painting for Bob-Omb Battlefield is blank
 * When you enter the Bob-Omb Battlefield paining, it suddenly changes to the Lethal Lava Land painting before going to the loading screen.
 * The only mission that can be chosen is named "TURN BACK".

TURN BACK

 * No red coins will spawn in the level.
 * The one-hundred coin star is unable to be collected in the level. Upon collecting one hundred coins, nothing will occur.
 * No metal balls will spawn in the level.
 * Luigi can be found on the other side of the bridge in Bob-Omb Battlefield. Getting in proximity to Luigi causes him to run away from the player in random directions. If you stop chasing him, he will stay still until you come close to him again. Once five coins are collected, Luigi will run to the cabin's door at the top of the mountain and then disappear.
 * Any yellow coins that the player collects will be numbered in the same way to red coins. Upon collecting a coin, the level's music will slow and the skybox, enemies texture's, and level textures will become darker and more morbid. Upon collecting a fifth coin, all the level's enemies will lie down as if they were dead, though they will not disappear. Once five coins are collected, the coins will no longer be numbered.
 * In the place of King Bob-Omb on the top of the mountain is what appears to be a small cottage. It looks old and broken down as well as out of place with the art style of Super Mario 64. Nothing will occur if you enter the cottage without collecting five coins. The interior of the cottage contains a bed, a hanging chandelier, a refrigerator, a lamp, a desk with a lamp and paper, and a bookshelf.
 * If the player enters the cottage and has collected five coins, the camera will zoom in on the chandelier, where Luigi has hung himself and a scare chord sound effect that sounds like a violin screech with loud piano banging. The game will then relinquish control from you and Mario will walk forward and then drop to his knees and sob. The sobbing animation loops for five minutes and then the screen will fade out with a Bowser silhouette like when Mario loses a life.

Continued Differences
After completing TURN BACK, the game continues in a more linear manner and is completely different from the base game at this point. The Bob-Omb battlefield room has been replaced with a hallway with two paintings on the front and back walls. This hallway will serve as the main hub area for the rest of the game. If the game is turned off and turned on again, Mario will spawn inside the hallway instead of outside Princess Peach's castle.

After TURN BACK
Mario's lives will be set to two, regardless of how many lives you had previously. The painting that Mario exits is a picture of Luigi hanging lifeless instead of the Bob-Omb Battlefield painting. This painting is inaccessible.The hallway is lined with expressionless toads wearing white robes who cannot be spoken to. The painting at the end of the hallway is a image from Google Maps of the return address that the player wrote on the envelope that they sent to the PO box in Utah when buying the cartridge from supermario64buynsell.com. Jumping into the painting, there will be only one mission accessible which is titled "Run, Don't Walk".

Run, Don't Walk
The level is a long flooded brick hallway with wooden platforms spaced evenly along the hallway. Mario will spawn on one of these platforms. When Mario jumps to one of the platforms, the camera will move to show behind Mario and reveal a black void advancing down the hallway silently. As the player jumps from platform to platform, the void will gain speed and eventually overtake Mario, making you lose a life.

After Run, Don't Walk
Mario will now have one life. The hallway now lacks some of the Toads lining it and the picture of the address now appears run-down, abandoned, and dis-used. The Luigi painting is still inaccessible. Jumping into the new painting of the address; there is one mission titled "I'm right here.".

I'm right here
The level is a small circular room consisting of all black walls, floors, and ceiling. The only feature of the room is a Mad Piano enemy in one of the corners. If Mario dies to the Mad Piano, an altered death animation plays instead of the usual one. This animation depicts Mario falling down onto the ground as his blood and guts spill all over the floor as the camera pans from an angle to a top-down view. While at the top down view; a distorted version of the Merry-Go-Round track plays as the screen transitions to an image of a photo-realistic sketch of the same frame of Mario's dead body.

After I'm Right Here
Mario's lives count is now zero. The hallway now lacks even more Toads lining the walls, and the picture of the address now appears visually damaged and broken, with chunks missing and cobwebs covering surfaces. Walking towards the painting causes the scene to shift.

You couldn't save her
The scene shifts to a panning aerial shot of Princess Peach's castle. The castle is crumbling and in ruin and the castle grounds are on fire. The skybox is also pitch black, with no stars in the sky. Bowser's laugh track plays on loop as the sound of children mockingly chanting "You couldn't save her" repeatedly plays. After the shot pans completely around Peach's castle, the screen switches to a headshot of Princess Peach with completely eyes appearing to be screaming accompanied by a loud screeching sound. The screen then fades out with the Bowser silhouette and goes back to Mario standing in the same place he was before.

After You couldn't save her
Mario's lives will now be zero, same as before. The hallway now lacks any white-robed toads and the painting of the address now looks even worse then before; with the building or area usually being on fire, collapsed in several places, and rotting, The level in the painting is now called "DIVE" and there is only one mission which is blank text.

DIVE
Mario spawns on a small island in the middle of a very large body of water, with no end to the water in sight. The islands only features are a single palm tree and a sign which only reads "DIVE". The water is dark and empty and contains no fish or other animals with very low visibility. The ocean seems to be endless, and the ocean floor cannot be reached. While swimming, Mario's power meter does not deplete. After being in the water for ten minutes, an enlarged Unagi will appear and attack Mario, killing him. The screen fades out and the game over screen does not appear.

After DIVE
The screen fades out into the picture of the address which is now completely decimated and in rubble. The image remains on the screen until the game is powered off. Powering on the game again, the player can select another save file and play the ROM hack again. Selecting a finished save file will display the image of the address and will be unable to be exited without turning off the console.

Reception
Upon footage of the ROM hack being released onto Youtube and then being shared in MIPS Hole spaces, the hack's technical aspects were overshadowed by the horror imagery, tone, and general story content; one user is cited saying "While the hack is very technically impressive, I mean they had to do a lot of programming and modeling for this, the actual content is just garbage. I mean it's not even scary". Roughly a week after the ROM hack's release, several MIPS Hole researchers started investigating the game, one of them even procuring a copy, and suspected that the hack involved the PAI in some way to create its content. They then reached out to the developer with questions of if the hack involved the PAI in some way. A person claiming to be "HandsomeChris" posted on the MIPS Hole wiki's ROM Hacking forum with a post answering the researchers questions.

Development
HandsomeChris responded on the ROM Hacking forum, saying: "I indeed developed [Buy N Sell] to use the [ Personalization AI], sort of as a technical test to see if the [PAI] could be harnessed to our own benefit, and it was a resounding success. I hard-coded the [PAI] to [personalize] the game in a specific way for every save file. Obviously the content that you see in the game is far different from the AI's normal behavior, but it wasn't that hard to force it to [personalize] the game in the way that I desired. By inserting my assets into the game as "[unused] content" I gave the AI the ability to use it, and then I simply altered the AI's code to perform a routine repetitively. However, I will not be allowing you all access to my research involving the [PAI], as it is far too valuable as an industrial secret to give freely to people on the internets."

Theorizing
Some have theorized that HandsomeChris was lying in regard to modifying the PAI, as efforts to do so in the past have failed. However, the ROM hack and its use of the AI are still shrouded in mystery. Only time will tell the truth.