The train conductor 'Porter' is based off of the Japanese song 'The Monkey Palanquin Carrier'. This is the reason he's a monkey.

Within the game's data is an unused squirrel character, named "Shakitto" (シャキッと, meaning "crisp" or "crunchy") in the Japanese version's files. The text "Rya~" (りゃ〜) is also placed directly after her name, though it's unclear whether this is meant to be an additional component of it or if it was a catchphrase.

Despite Shakitto appearing to be a scrapped villager, her filename, ac_ev_dokutu, indicates that she was likely conceived as a special character. The "ev" component is used in the game's data for special characters that occasionally visit the player's town rather than being permanent components (e.g. Redd, Sahara, Wendell, Gracie, etc.), while "dokutu" is likely a truncation of "dokutsu," which can refer to either a cavern or a hole in the ground. The latter implies that she would've buried items for the player to dig up, similarly to an action that villagers can announce on the Bulletin Board in the final game.

Because no other code for Shakitto's intended function remains in the final game, spawning her in as a villager with Action Replay codes instead results in her using various bits of preexisting character data.

Animal Crossing is only one of five different versions of the same game, three of which were only released in Japan, and one of which was only released in China. The first version was for the Nintendo 64 in 2001, entitled "Dobutsu no Mori", which translates to "Animal Forest". The second version, "Dobutsu no Mori+", was an enhanced remake of the original game, released on the GameCube. This was the version that would be localized as Animal Crossing in North America and Europe. The fourth version, "Dobutsu no Mori e+", was a second enhanced remake released on the GameCube including e-Reader card content. The final version was a Chinese localization of the original Nintendo 64 version, Dòngwù Sēnlín, released five years later in 2006 exclusively for the iQue Player.

The NES games Balloon Fight, Baseball, Clu Clu Land, Clu Clu Land D, Donkey Kong, Donkey Kong 3, Donkey Kong Junior, Donkey Kong Jr. Math, Excitebike, Golf, Ice Climber, The Legend of Zelda, Mario Bros., Pinball, Punch-Out!!, Soccer, Super Mario Bros., Tennis, and Wario's Woods can be played in the game. They can be acquired through Game Boy Advance connectivity, e-Reader, and secret codes to Tom Nook. However some can only be obtained with the use of a cheat device which can also unlock all of them at once.

If you you use an Action Replay, you can access the paper airplane item in your inventory. If you place the item on the ground, walk off screen, and come back, the paper airplane will duplicate itself. Pressing the A button while on top of the paper airplane will make it disappear visibly, but will still exist in the system's memory. Letting the airplane multiply too much can crash the game.