like any game, animal crossing can be hacked and broken to fit the desires of the player. there are similar hacks for every game - simple things, like using action replay to fully unlock catalogs, the museum, get extra money, et cetera... and more complex things like map editing or custom villagers. i've always had a huge interest in animal crossing hacking and map editing, and i can't really explain the happiness it gives me when i look at it or do it myself. this page doesn't list hacking by game, since that would quickly become redundant (most games have basically the same kinds of hacks) but instead it lists it by some of my favorite instances of hacking.

probably my favorite of all the various hacks in animal crossing is the HDLC in city folk. HDLC stands for 'hacked downloadable content,' but i've also seen it called 'hacked distributed items.' custom items are something you can find in most hacked animal crossing games, but city folk's HDLC is particlarly interesting because it quite literally spread like a virus. having someone with HDLC visit your town would give you the 'virus' and put the HDLC items into your store rotation. because it spread like, well, a virus, there was a lot of worrying about if these items would damage your wii. thankfully - that turned out not to be the case!

so how does it work? i don't have a wii, so this is mostly me speculating and going off what others online have said. there are (or were) unused item slots in city folk, reserved for official DLC that nintendo would put out over wiiconnect24. HDLC essentially just took the place of these empty slots. it gets a little bit more complicated when you add in OHDLC, a subtype of HDLC. it stands for 'overlapped hacked downloadable content.' there are only so many slots, so some of these items 'overlap' slots taken by other hacked items. OHDLC is technically obtainable by people without any hacking/cheating devices, but it prevents obtaining any other DLC that takes up that slot. it's all very complicated...

some of the most famous examples of HDLC are the dimentio mask, shiny blue pikmin hat, and the red and blue lightsabers. there's other ones too, like pokeball furniture, blue carnations, and a guitar you hold by the neck and swing around like a sword. i don't think that's how you're supposed to use it...

custom villagers
self-explanatory! in most of the animal crossing games, people have figured out how to re-skin and re-name their villagers to become custom characters. some people have even figured out how to go a step further and replace the models entirely, allowing for completely different creatures to feature in the game. it's something i would like to try my hand at myself! and then maybe i can replace the examples here with my own :p