There are numerous unused items in the game's code, all of which can be accessed with cheats. These include:
• A blue fish, possibly used to test the fishing function.
• DUMMY, a glitch item appearing as a white triangle with Japanese text on it reading "ダミー", which translates to "DUMMY", hence the name. Once in an Igloo, you obtain the item in a similar way to other furniture. The animal might want to play a game where he or she will ask you to pick two cards. One card you have to buy something and one card you will get a free prize. The prize card may sometimes be a DUMMY card.
• MBG, a glowing yellow box that moves back and forth, can push the player around (sometimes making them float), and can modify the spread of Paper Airplanes.
• A tool labeled "Sickle", which makes the player function as if they had nothing in their hands. This item dates back to the development of the original Doubutsu no Mori, with an early inventory sprite for it appearing among assets uncovered in the 2020 Gigaleak, a large-scale breach of internal server data from Nintendo. The item appears as a toolbox when dropped, a feature present in Doubutsu no Mori (as well as several later games in the series) but not in Animal Crossing.
• An "Unknown Item" that appears in the player's inventory as a box with a question mark, and appears in homes as a clone of the DUMMY item.
• Paper Airplanes, which, if you place on the ground, walk off screen, and come back, will duplicate itself. Letting the airplane multiply too much can crash the game. Pressing the A button while on top of a paper airplane picks it up, and the player can then throw it using the Z button; however, they cannot move after it lands, softlocking the game.