- Rapid image sequences are intercut throughout "Love! Anger! Kvetching!", symbolizing the trauma Duckman's uncle Mo has put him through. Among the nastiest are Uncle Mo as a smiling and fanged devil and the grotesque Duckman caricature seen in the adjacent image.
- "The Gripes of Wrath": Act three, where the world became a crime-ridden, red skied hellhole. Granted, this section had some funny jokes, but still, what a frightening place.
- On the other end of the spectrum, it's a touch creepy how relentlessly happy and supportive Bernice is when the world becomes a utopia. Hell, the Utopian world itself, while better than the alternative, has a very disturbing Brave New World feel to it.
- There's also Duckman's daydream in the first act where a terrorist threatens to blow everyone's heads off; upon choosing orange juice, the scenario ends peacefully, as the O.J. reminded the terrorist of his carefree younger days. But upon choosing tomato juice, Duckman accidentally drops the glass, sending the already unstable terrorist into a fit ("Blood! Blood! So much blood! I've been very bad, mother!") and inadvertently shooting a scientist in a nearby building, who drops a chemical formula that destroys the Earth. The pure terror of this sequence is lessened a bit by the newspaper headline: "Earth destroyed, Duckman to blame", but still.
- Duckman eats Fluffy and Uranus in "All About Elliot" (at the latter's suggestion). As if that didn't create such a Squicky mental image, they're utterly horrified and disheveled the next time we see them.Fluffy & Uranus: Please don't eat us! Please don't eat us! Please don't eat us!
- "Sperms of Endearment" ends on a disturbing note. After spending much of the episode thinking she might be pregnant with Duckman's donated sperm, Bernice decides it's for the best there aren't any more of his offspring. As if to prove this, it pans to show a psychotic children resembling Duckman burning conman Terry Duke Tetzloff at the stake.
- "Color of Naught", the third act when Beautex (which was thought to be a beautifying cream) reduces everything it touches to sketch outlines. There's one scene when Duckman is frantically climbing a tower which is quickly being erased from the ground floor up.
- Fluffy and Uranus channel this in "Short, Plush, and Deadly". Despite maintaining their pastel colors and bows, they Hulk Out and violently pursue Duckman and an incapacitated Cornfed. Of course, the episode ends with Nightmare Retardant when they're brought back to normal, with help from Jim Bailey.
- In "Noir Gang", Cornfed has a dream about getting it on with Tamara. But it's cut short by a bomb-strapped Duckman standing outside. Who then calmly tells Cornfed he's his best friend before detonating.
- This is more in line with Fridge Horror, but Agnes successfully hid away as Grandma-Ma without anyone knowing. On one occasion, she even flashes a Slasher Smile to the audience.
- Agnes already brings enough Nightmare Fuel to the table. She's an Ax-Crazy and deceptively strong robber who posed as a family member and then assaulted said family (including a rape attempt on Duckman). And she's still there by the end of the episode'', having managed to pull a last-minute switcheroo, leaving Grandmama to be imprisoned in her place. She stays with the family for about a season afterwards.
- Tami from "The Tami Show" is an attractive woman who drugs Beverley so she can take over Duckman's family, Yandere style. She viciously kills a neighbor's gardener who witnessed her drugging with a trowel, and survives ungodly amounts of damage from electrocution to being maimed by a ceiling fan, all while sporting an unholy Nightmare Face. She even emerges from the bathtub in a murderous rage and tries to drown Duckman down the drain, only to be devoured by a shark. But the episode ends with her hand rising from the bathtub. And to be make things worse, she appears in a cameo in the final episode at the three weddings. Negative Continuity withstanding.
- The shows surreal animation causes a lot of this by accident, even just character design or one-off gags look creepy.
- The monster representing Duckman's guilt over his wife's death and him being left to try and build a new life for himself, seen in the episode "Psych".
- The aliens from Betamax creating a Nazi regime where the only difference is the swastika is now a silhouette of Duckman walking."We'll do it in the name of Dod!"
- One of Duckman's possible future selves in "The Once and Future Duck" is a masked psycho on an eight state chop spree."Always more killing, more killing, MORE KILLING!"
- The ending of "The Mallardian Candidate", due to the Big Brother Is Watching motif.
- Duckman's face after going through the MRI machine in "They Craved Duckman's Brain!" Yikes.
Nightmare Fuel / Duckman