1. Invader Zim Nickelodeon Animation Studio This show is the king of all messed up cartoons. You don't come back from seeing Zim steal kids' organs and replace them with stuff like calculators or cats. But that's certainly not all! This show's got hypnotizing pimples, a radioactive hamster named Ultra Pepe, evil alien babies, a room with a moose, and the iconic DOOM SONG!Most Bizarre Episodes: "The Most Horrible X-Mas Ever," "Bloaty's Pizza Hog", and "Dark Harvest." 2. Goosebumps Protocol Entertainment / Fox Kids / Via youtube.com Green slime and a dog with glowing eyes? These could only mean one thing: Your 6 year old self is about to have nightmares for weeks. Every 90s kids' fear can be traced back to this show: fear of roller coasters, fear of dolls, fear of snakes, and even fear clocks.Most Bizarre Episodes: "The Blob that Ate Everyone," "Say Cheese and Die," and "Revenge of the Lawn Gnomes." 3. Super Duper Sumos DIC Entertainment / Via youtube.com Hmmm...this show may have been a little racist towards the Japanese. On top of that, Super Duper Sumos was filled with homosexual undertones as this male trio often fought crime with their butts and lauded themselves on their own butts. And that's all that this show really had: Stereotypes, butts, and gay subtext. Most Bizarre Episodes: All 26 of them 4. Courage the Cowardly Dog Cartoon Network This show didn't mean to scare us, but holycow did it scare us! One thing that bonds millenials is the fear of King Ramses if someone stole his slab or a haircut from Freaky Fred. You don't make a show with alien duck brothers, a weremole, a vengeful moon spirit, and a sassy, uninterested computer and expect normalcy. Most Bizarre Episodes: "The Demon in the Mattress," "Everyone Wants to Direct," and "Hothead." 5. Ren and Stimpy Nickelodeon What…was…this…show? These two are supposed to be a Chihuahua and a cat, but Chihuahuas don't rip out the nerves in their gums and cats don't demand dogs to saw wood on their backs the last I checked. And the ultimate sign this show needed to calm down: It got picked up by Spike TV.Most Bizarre Episodes: "Ren's Toothache," "Son of Stimpy," and "Insomniac Ren." 6. Mr. Meaty Nickelodeon Mr. Meaty: The most horrifying, non-horror show that ever was. Nothing was okay about this show: the grungy puppets, the radio-controlled manager, the farcical food and bodily noises, and a once cryogenically frozen, 100 year old CEO with purple skin. This show would turn anyone into a vegetarian. Most Bizarre Episodes: "Wedgelor," "Kids Party," and "Parkerina." 7. The Amanda Show Nickelodeon The show has to be included because it probably drove its star crazy. Of course everyone loves the dancin' lobstahs, Debbie as much as she likes eggs, the wacky commercials (the popcorn pants were genius!), and the toothy Crazy Courtney. And we all still want to win five dollars and call in a dare to Sharon and Toby.Most Bizarre Episodes (Sketches): "Mammal-O's," "Kelly the Lifeguard," and every "When…Attacks" segment. 8. Aaahh!!! Real Monsters Nickelodeon / Via youtube.com A darker version of Monsters Inc., this was one of those weird shows that no one batted an eye at like CatDog, but it was the strangest of them all. I mean, a large-mouthed torso that carries its eyes and a green, four-legged teacher who wears red pumps and has Tim Curry's voice? That's weird. Pretty awesome, but weird. Most Bizarre Episodes: "Cold Hard Toenails," "I Dream of Snorch with the Long Golden Hair," and "A Wing and a Scare." 9. SpongeBob SquarePants Nickeldeon Yes, SpongeBob is the king of early 2000s cartoons, but even royalty can be a little messed up. Who can get the clay recreation of Mr. Krabs screaming for MORE jellyfish jelly out of their heads?! We bow down to you, SpongeBob, but you're the reason why none of us can focus these days. Most Bizarre Episodes: "I Was a Teenage Gary," "Rock Bottom," and "The Sponge Who Could Fly." 10. Butt-Ugly Martians Nickelodeon Um…what? But hold on a second….what? This short lived show was short-lived for a reason. Well, several reasons actually. A terrible title, atrocious animation, and yet so boring, but it was enough for your 9 year old, ADD-ridden mind. And uh…yeah, there's not much else to say about this show. Except…what?Most Bizarre Episodes: All 26 of them. 11. Are You Afraid of the Dark? Nickelodeon Unlike the campier Goosebumps, Are You Afraid of the Dark? took itself very seriously and it seriously scared the pants off us. Sometimes, a little too much so with off-screen deaths, twist endings galore, and one really gory monster. Submitted for the approval of the midnight society, I call this show really messed up!Most bizarre episodes: "The Tale of The Silent Servant," “The Tale of Many Faces,” and "The Tale of the Pinball Wizard." 12. Fairly OddParents Nickelodeon Here's another cartoon juggernaut that, despite its popularity, was still pretty random. Like Phillip the girl nickel? What? A family with huge boils? WHAT? An octopus alien that talks like a bro named Mark Chang? WHAT?! Compared to the cartoons of yesteryear, you must wonder what our parents were thinking. Most Bizarre Episodes: "Five Days of FLARG," "Tiny Timmy," and "Super Bike." 13. The Adventures of Jimmy Neutron: Boy Genius Nickelodeon Llama and pie obsessions, evil pants, a villain who can't finish anything (sounds like college all over again), and robotic egg aliens. But is any of this that surprising when its source material was a movie about battling a giant, green space chicken and defeating it with soda? At least you'll never forget that poultry can't burp. Most Bizarre Episodes: "When Pants Attacks," "Sheen's Brain," and "Sleepless in Retroville." 14. Ed, Edd, n Eddy Cartoon Network This show was the Rocky Horror Picture Show of cartoons. It was weird, highly popular, and yet still considered a cult show. But maybe that's for the best since you wouldn't want anyone else to be scarred by the image of Eddy running with his green tongue flapping in the wind. It's not something anyone would soon forget.Most Bizarre Episodes: "One + One = Ed," "One Size Fits Ed," and "Urban Ed." 15. Yakkity Yak Nickelodeon / Via youtube.com Let's just summarize this gem of a cartoon, shall we? In the town of Onion Falls, a yak in a fur coat, who aspires to be a stand-up comedian, goes on adventures with his pineapple friend, Keo…Yep. But at least it had a cover of one catchy as hell 1950s song as its theme. Don't talk back!Most bizarre episodes: Season 1, Episodes 1-26. Season 2…Oh, there was no Season 2….Oops.