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Nightmare Fuel: Rocko's Modern Life
"YOU PUT ME IN A JAR?!"
Earlier in the episode, Rocko ends up in a closet full of organ jars, all of which have black holes for eyes and are all moaning "Don't cut us, Rocko..." in a horrifying deep voice!
The red thing at Rocko's side beating like a heart earlier on in the episode.
The episode in which Heffer choked on a chicken bone and Rocko had to enter his body to find his heart and restart it. Of course, Heffer's insides were as creepy as could be, and his heart was a realistic heart.
The Hopping Hessian episode really did a good job of being surprisingly unnerving for a kid's show.
"Who took those pictures?!"
The episode "Who's For Dinner" had Heffer's house which was a family of wolves who were carnivores. Carnivores who are eating what is obviously completely sentient food. Rocko opens up a mirror in the bathroom, which reveals three pigs being Bound and Gagged, and Rocko responds by merely closing the mirror to leave them to their fate.
There's also the room full of girls who look like Red Riding Hood.
Rocko slammed the mirror shut on obvious impulse and looked horrified at what he saw, which doesn't seem to fall in line with someone "leav[ing] them to their fate." He could, y'know, open it back up again.
Really Really Big Man's nipples coming into play.
Most of "Ed is Dead".
Mr. Bighead's vision of Heffer, Mrs. Bighead, and Rocko as devils in "Cabin Fever". "Are you okay, Mr. Bighead?" *shudder*
The crazy bus driver from "I See London, I See France".
The episode "Power Trip" where Rocko lets the power go through his head when Mr. Smitty goes on vacation. After hiring Filburt as a temporary assistant, Rocko pushes a button in his boss' office that he was specifically told not to. Later on, the pressure becomes more intense for Filburt when he was trying to attend to the angry customers' needs and Rocko's as well. Eventually, Rocko was revealed to have similar features (i.e. portly physique, grouchy demeanor, etc.) to his boss, only with deranged eyes, much to Filburt's horror. If it weren't for Really Really Big Man calling Rocko out, the both of them would have horrible futures.
The scene in "Love Spanked" where Rocko meets his date's father who seems like a nice guy but then he transforms into a horrifying grotesque monster saying that he will kill him if he even touches his daughter.
The scene in "No Pain, No Gain" when an ox gets his arms ripped off by arm crunchers with blood spraying from the stumps.
The smoking bluejay coughing up his heart in "Flu-In-U-Enza." Also a good Getting Crap Past the Radar moment as not only does it show someone dying, but it also shows a cartoon character smoking, something that has fallen out of favor in a lot of Western children's cartoons.
Three words with regards to the episode "Nothing to Sneeze At": Amphibial Globo Bloaticitis.note It's a disease that basically causes your head to swell to three times its normal size (to the point of seeing veins) and appear like a huge tumor on your neck. This happens to Bev, much to Ed's horror when he wakes up smothered by her flesh.