Adaptation Displacement: Many fans of the cartoons don't realize that it isn't an original Halloween Special. Not only that, but the specials only adapt the first two of several books. And that's not getting into the fact that it has numerous comic book adaptations.
Cult Classic: These specials never reached popularity on a mainstream level, but they're fondly remembered by those who grew up watching them on Cartoon Network.
Fountain of Memes: Jimmy's over-the-top personality has resulted in him being prime meme fodder, such as when his face freezes or when his ear comically enlarges when he's being nosy.
The bugged eye Wild Take. Every time her cousins freak out they had their Black Bead Eyes turned into bugged out eyballs. Plus it overlaps with a Nightmare Face.
In Revenge of Jimmy, the second time he attempts to cancel Halloween the Fright Side blinks out of existence. Scary Godmother is left stranded on her broom in a black void, with Skully, Harry, and Bug-A-Boo hanging on for dear life. Hannah manages to fix things, of course, but Fridge Horror comes into play when you think about what happened to everyone else in the Fright Side, including Count Max, Ruby, and Orson, when it ceased to exist.
Jimmy gradually mutating into a more demonic parody of himself as he does his attempts to cancel Halloween. His face distorts and he grows fangs. It's enough to scare Bug-A-Boo! Thankfully, said scaring was able to help Jimmy realize the monsters aren’t evil when Bug-A-Boo complements him on it, allowing him to regain his Halloween spirit.
Orson and Hannah seem to be flirting in a few scenes, confirmed in the book that Orson does have a crush on her.
Katie and Daryl. Daryl has a crush on Katie but it's ambiguous on her side.
Unintentional Uncanny Valley: The animation has not aged well, with the character designs varying from a little unsettling to downright frightening. The models just seem so....off. Some of the most notable cases include the Black Bead Eyes on most of the human characters and the humanlike lips on Harry. For most people who grew up with the special, it also crosses into Narm Charm.
Comic
Complete Monster: The Master is shockingly vile for such a lighthearted series. The Master is a vampire who runs a "Summer Ghoul" camp which he advertises as a place to teach young vampires to hunt. But in actuality, it is a place for him to get slaves where he forces the children to hunt for him while he continues to be lazy. The Master also hypnotizes the carrier animals used to deliver messages from the families of the students, making the carriers lie that everything is going fine. A student caught him doing this, so the Master tossed him outside to slowly burn to death in the sunlight. When his sister begged the Master to save her, he mutilated her by pushing her face into the sunlight. When a new student arrives at the camp named Orson, the Master plans to eat his human friend Hanna and Orson himself.
, Jimmy could be a Designated Villain. He's seen as a Shell-Shocked Veteran who has neglectful parents (who seemingly don't care that he threw everything out, and hasn't showered in a year), and who suffers so much from PTSD that he goes so far as to destroy an entire pumpkin patch to the point of getting a limp from it.