When kids used to watch cartoons on the tube, Nickelodeon was probably one of those networks they turned to, to get that fix. At that age, kids didn't quite catch adult-aimed innuendo. Cartoons are thought to be only innocent and pleasant, but sometimes, writers realize that's not always the case. While some of these classics did make it past the censors, unlike others, they are still creepy to this day. Nickelodeon is known for turning out classics such as Rugrats, Hey Arnold!, and Are You Afraid of the Dark? and amongst the season's viewers know and love, the creepiness is still there.

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Looking back, kids had every right to be disturbed, because certain Nick episodes are just as creepy now, as they were then.

Angelica's Worst Nightmare: Rugrats (7.7)

Big baby towering over Angelica

For 13 years, Rugrats was one of the most popular cartoons on television. The adventures that Tommy Pickles and the gang used to get into were fun to watch, and probably gave kids ideas of their own. Most of the episodes were about life lessons and friendships, but there's one episode, in particular, that is hard to ignore.

In season three, an episode named "Angelica's Worst Nightmare" centers around Angelica and the possibility of her mother having another baby. Since Angelica thinks the world revolves around her, she fears her only-child status might be in the midst of destruction. After feeling neglected because of the news, Angelica has a dream in which a large and very low-voiced baby terrorizes her. He steals her food, grows a foot taller out of nowhere, and tells her she's the "old baby," which would terrify any only child.

SquidBob TentaclePants: SpongeBob SquarePants (7.7)

Squidward entwined with SpongBob

There are a lot of weird and bizarre SpongeBob episodes, but one stands out, that might be a little much. In Season 4, Episode 8, Sandy Cheeks shows SpongeBob her transporting machine, prior to him going to his shift at the Krusty Krab. Knowing SpongeBob, his actions usually become misadventures, and the machine doesn't mesh well with him. When he arrives at work, the machine malfunctions and somehow fuses Squidward and him together.

Even though SpongeBob doesn't think it's such a bad situation, Squidward is freaking out. But, it's really the end that's terrifying, because when Squidward tries to fix what happened, he ends up morphing everyone around him together, turning them into a disgusting creature that would make any kid run out of the room in terror.

Arnold Visits Arnie: Hey Arnold! (7.9)

Arnold and Arnie looking at one another

In the final season of Hey Arnold!, Arnold decides to go visit lookalike Arnie in episode 12. Even though Lila, Arnold's crush, finds Arnie attractive, Gerald knows something is up with his best friend's cousin, based on an interaction he had with him previously. Arnie collects lint, constantly talks about gum, and is always snorting, which would make anyone uncomfortable.

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The fact that Arnie looks like Arnold is weird, and maybe even his mannerisms, but what's really odd is his hometown. Everything looks like Arnold's life, and the people in it, but the people have weird personalities or combined physical features. When Arnie suspects that Arnold is hitting on his girlfriend, he turns into a legit "Evil Twin," which is very disturbing.

Dark Harvest: Invader ZIM (8.5)

Drooling character and other character side-eyeing him

Perhaps one of the creepiest episodes from a Nickelodeon show is from Invader ZIM, called "Dark Harvest." Invader ZIM is widely known as an off-the-kilter show, with some weird characters, but this episode took it a step too far. In fact, according to an MTV article, a convicted murderer named Scott Dyleski once admitted to getting inspiration from this very episode.

Basically, the entire episode is about harvesting organs, all because Zim has to appear more "human-like" for a health examination. Zim then starts to meander around the Skool, taking everyone's organs and replacing them with everyday objects.

Ren's Toothache: The Ren & Stimpy Show (8.7)

Ren smiling with rotten teeth

The Ren & Stimpy Show was once considered a cartoon for kids, but in all frankness, it definitely wasn't. Nickelodeon aired this show from 1991 to 1996, and just by watching one episode, parents knew it might not be the PG they were used to, and especially if they saw the episode "Ren's Toothache."

Ren doesn't like to brush his teeth, and since no one is around to tell him otherwise, he deals with the terrible consequences and starts to lose his teeth. Cue to the scenes of his poor teeth cracking and turning to dust, and that's enough for anyone to visit the dentist.

Zeke The Plumber: Salute Your Shorts (8.9)

Masked man with a wrecked nose in Zeke the Plumber episode

Salute Your Shorts only made it to two seasons, but in that time, "Zeke the Plumber" happened, and it still has the potential to haunt nightmares. Even though this show was meant for kids, there was something bound to happen to a group of teen campers in the woods. In Season 1, Episode 3, one of the camper's, Bobby Budnik, decides to tell a story about Zeke, a noseless custodian who haunts Camp Anawanna and uses a plunger to suck secrets out of campers' heads.

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First off, going to camp was scary enough, let alone thinking there was a noseless man lurking around, waiting for his next victim. Second, when Zeke finally showed his ugly mug, it was terrifying. His backstory and appearance are quite similar to the infamous villain, Freddy Krueger.

The Tale Of Laughing In The Dare: Are You Afraid Of The Dark? (9.1)

Collage of screencaps from Are You Afraid of the Dark's episode The Tale of the Laughing in the Dark

If viewers were willingly watching the show Are You Afraid of the Dark, they knew they were in for some scary campfire stories, with some pretty creepy characters, too. As fans know, there are some episodes that were scarier than others, and "The Tale of Laughing in the Dark" is among them.

Leave it to this show to highlight how scary clowns are when a character named Josh steals a clown's nose in a funhouse at Playland. He steals its nose because supposedly, the clown haunts the joint. Josh finds out that he made a grave mistake when Zeebo, the terrifying clown, pays him a visit that isn't so welcoming.

The Tale Of The Dollmaker: Are You Afraid Of The Dark? (9.1)

Collage of screencaps from Are You Afraid of the Dark's The Tale of the Dollmaker

In Season 3, a little girl named Melissa decides to go visit her aunt and uncle in the country for the weekend. Another little girl named Susan Henderson moves in next door, exciting Melissa because she hopes to make a new friend. Abruptly, the Hendersons move back to the city, and when Melissa goes to investigate their old home, she realizes Susan left her dollhouse.

Melissa eventually realizes Susan is trapped inside her dollhouse and is turning into a ceramic doll in the process. In fact, the scene where Susan's hand snaps off because it's ceramic is horrifying and not for innocent eyes. This episode is haunting to this day even though it ended on good terms.

The Puppetmaster: Avatar: The Last Airbender (9.2)

Airbender characters clutching each other with scared looks on their faces

In the episode "The Puppetmaster," the Avatar gang goes to a creepy village where various disappearances are happening under mysterious circumstances. They meet an old innkeeper named Harma, who seems like she wants to help out her visitors; far from it, really.

Her real motive is capturing people with dark magic and using "bloodbending" skills. The entire vibe of this show is eerie due to the fact Harma is kidnapping people and using horrific, immoral magic.

Graveyard Shift: Spongebob Squarepants (9.4)

Evil character looking at Squidward and Spongebob

SpongeBob's Mr. Krabs is known for being a cheapskate who only looks out for himself, but he stoops to a new level when he deems the Krusty Krab to be open around the clock. While SpongeBob is thrilled, Squidward is over it. As the night progresses, Squidward starts to pick on SpongeBob, telling him a story about the "Hash-Slinging Slasher," a fry cook who accidentally chopped off his own arm, and replaced it with a spatula he found.

While it's all a ruse to scare SpongeBob even more, things start happening around the restaurant, and they both start to believe this entity is real!

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