Lucky's house seems to be based off of Egyptian tombs. Not helping is the fact that he has K.K. Dirge playing in his house...
Luckily, Lucky has a "Lazy" personality, which softens the blow.
Furthermore, the City Folk/Let's Go To the City manual claims that Mr. Resetti might be this to younger players.
Funny enough, Resetti ended up being optional in New Leaf because according to Nintendo, he scared the younger players and even made a few cry in some cases. This can end up averted if you aren't the mayor, though. Even if you are not the mayor, this opens the Reset Center project FOR the mayor. And the devious siblings rejoiced.
In the original GameCube version the music plays at 11:00 p.m. as well as the music that plays at midnight can sound really spooky for such a lighthearted game like Animal Crossing.
The music at 2:00 a.m. also made many players jump because of how out of place it sounds compared to not only the rest of the late night music, but also the rest of the hourly music in the game.
4 AM in New Leaf. While the music is unsettling enough on its own, an industrious Japanese played created an entire village meant to be visited in dream mode that is Creepy Pasta incarnate, and it is always 4 AM when visited.
Coco. How many people have seen her walking around with her back turned, go to talk to the new villager and get a load of...this◊? No, her mouth is not open because she is shocked, she always looks like that.
Her face was probably meant to look like a Gyroid, or more likely, a coconut, but it's still sort of a strange face to give a character.
And guess what song is playing in her house? Yup, the aforementioned K.K. Dirge.
In the GameCube version, if you were unlucky enough to not save when you're away travelling on the train, you lose your money, your items, and your face. Yep, imagine the horror of stepping out of your house, turning around to the camera and having an empty, gaping face◊. Empty eye sockets, open, expressionless mouth, warty skin, and a disturbing resemblance to a ReDead. Apparently, it was meant to resemble a Gyroid to remind you to save.
Perhaps this is the same fate that became of Coco.
Rasher. He's a boar with quite a few visible scars on him.
In all games, the piranha, when in an aquarium, will repeatedly bash its head against the tank towards the player when they come close, clearly trying to bite the player. Though, it quickly becomes annoying after the initial shock wears off.
The tarantula in Wild World onwards. Thankfully rare, if it sees you approach carrying a bug net, it flips out and attacks you. The horrifying part of this is that your character PASSES OUT and the screen fades to black. Luckily you end up in front of your house no worse for the wear, but it's still a horrifying event in a game where the seemingly-worst fate for your character is being stung by bees.
The scorpion does the same. And the bees themselves aren´t much better. When you shake the trees, sometimes a beehive falls. Your character gets an Oh Crap expression and if you're not quick enough to capture one of them or run into either your or someone else's house, the bees will sting you mercilessly, causing some rather severe wounds on your face.
Though, these all quickly become more annoyances than anything. Either you use 400 bells for medicine and keep playing (if you got that far into New Leaf, if you're playing that), or you save and quit, then reload it. As for fainting and getting sent back, it just wastes time.
In New Leaf Uchi/Big Sister animals will give you free medicine upon noticing your stings.
With New Leaf came the possibility to share dream versions of your town via Internet. Inevitably, creepy places started popping up, like...
Hypno K.K., a song that is terrifying in its own right, has been infamously used with Aika village to the point where the song can barely be brought up without any mention of the town.
There's also K.K. Synth, used in a maze in one of the houses. It combines Nightmare Fuel by being rather sad.
Although the dream town is not completely empty, it still feels creepily vacant; insects and fish never spawn, main street is blocked off by a perpetually frozen train, and the town hall is closed. However, the worst has to be Re-Tail, sounding almost post-apocalyptic; when interacting with the door to the shop, it reads,
"Re-Tail: Temporarily closed forever."
Though granted, every Re-Tail in the dream world says that. But Aika's atmosphere makes it feel like it just "shouldn't" be like that, despite being normal.
Every dream Main Street is also blocked by a train, softening things a bit... But, again, given Aika's atmosphere, it still works. It almost makes you wonder what Main Street would look like if it could be altered to match the rest of the town.
Another horror village is Hitokui, the cannibal village. While it's not as ambiguous or well-known as Aika, it's very detailed and disturbing. You can find an in-depth walkthrough here.
There's also the town of Shachipanda, which features a little girl, a fallen superstar, a drug addict, and some very creepy basements. The dream code is 2100-0784-7385
4800-2398-3734 is a town called Aniville that gives off the boarding school of horror themes...as well as some Silent Hill feelings to it...
Although not an actual Dream Town, with Animal Crossing Plaza for the Wii U allowing people to share Dream Town codes, Video Game Cruelty Potential arose. Simply put, people could share these or even MAKE THEIR TOWN scary, and then people wanna just kick that Wii U cotroller.
The original Animal Crossing will randomly start up with a deep voice saying "Nintendo" not unlike the one in Luigi's Mansion, and then while it usually shows a random character walking around, this time it shows a villager carrying an axe randomly chopping down trees. Here's an example of this
One of the possible conversations between "Grumpy" and "Peppy" villagers. It starts off innocent enough, but the conversation ends up saying "I keep an (insert random object here) under my pillow when I sleep" from the Peppy villager. In this Peppy villager's case, she says "I keep a knife under my pillow when I sleep". The Grumpy villager will have a look of shock and says she's nuts as the chat ends. Though just awkward randomness, it is very unsettling.
In New Leaf, one of the reasons an Uchi villager can give for wanting to move is because she wants to take part in a gang war. Yes, its mitigated by the fact that moved out villagers occasionally visit your Main Street, but still!