Alternate Character Interpretation: It is possible to see Stanley as not so benevolent troll, considering he dreams of a land where all trolls are essentially copies of him (even if supposed to be "good") and, in the end, he covers New York in vegetation. Whether he is simply delusional or actively malevolent is up to the viewer.
Ass Pull: Gnorga discovering Stanley's activities in Central Park by hearing the sounds of Rosie's crying.
Big-Lipped Alligator Moment: The boat ride suddenly enters Stanley's dream land which he apparently created out of nowhere, we see all kinds of happy things that have no relevance to the story, and when the sequence is over, nobody mentions it again.
Dork Age: Yet another ill-fated outing for Don Bluth, and widely considered by many to be rock bottom in the director's career.
Glurge: Stanley's vision of a "perfect" world, even more so than everything else in the film. Basically, it's a sickeningly-sweet world filled with trolls who all look and think exactly like him.
Idiot Plot: Gnorga banishes Stanley all the way to New York City, without even knowing what Llort meant to suggest, and she banishes Stanley to New York City, far removed from the trolls' domain. On the kids' side, they only get themselves involved because the housekeeper neglected to keep a closer eye on them, so they freely walked out of their own apartment without anyone noticing. Later, Stanley is only discovered to be enjoying his exile because Gnorga just happened to be hearing Rosie crying out of all the babies who are crying at any given time, and she still goes to end him even though Stanley can no longer threaten her reign over the trolls.
Inferred Holocaust: The movie ends with all of New York being engulfed in vines and flowers. It's meant to be heartwarming, but ends up looking like some sort of supervillain takeover, or a scene right out of Life After People. It's not even made clear if it's just supposed to be another dream sequence.
Misblamed: Sorry, Gary Goldman, but better marketing would not have saved this movie.
Narm Charm: "I'm a bad troll, a very bad troll..."
Nightmare Fuel: The ending; it's not supposed to be, but it is. Long story short, Stanley covers all of Manhattan in vegetation. This is treated as something heartwarming.
There's a scene in Gnorga's Villain Song wherein she turns a bat to stone. It's worse than it sounds; one would expect her to just touch it and have it turn to stone then fall, right? Wrong. Instead one of its wings turns to stone and it desperately tries to flap away while the rest of its body slowly starts to turn to stone as well. The poor thing perches on a skull and desperately tries to escape...and then its entire body turns to stone. And then it blinks.
Stanley seems waaay too happy when Rosie, a toddler, kisses him.
Gnorga almost sounds orgasmic when she hears Rosie crying.
Padding: Loads, prominent examples being when the flowers perform a cheesy dance to cheer up Rosie and when Stanley takes the kids to a world of his own.
Rooting for the Empire: The villains of the film, Gnorga and Llort, are far more popular and liked than the actual protagonists, Stanley in particular.
Gus on a smaller scale. He spends most of the first part of the movie as a kind of Anti-Hero. And he's the one willing to fight for his ends, unlike Stanley, the supposed hero who would rather cower. The fact that he calls Stanley out on his behavior is another reason that even people who dislike the movie like him.
Ron the Death Eater: Stanley gets this treatment from some viewers, largely due to his glurge nature, not to mention the similarities between his actions in the film's ending, and the ending to the Little Shop of Horrors Director's Cut.
The Scrappy: Stanley himself often qualifies as this due to his sickeningly sweet personality and cowardice. And that's not even mentioning what he apparently does to New York at the end.
Invoked by the director himself, who had hopes that Stanley could be written as a much more interesting and flawed character with a much more engaging history between Gnorga's empire and himself. Unlike his partner, however, Bluth blamed himself for hastening the production to create what felt more like a child ripped out of the womb than a finished, well-produced film.
Llort's hand waves regarding why he would rather not just let Gnorga stone Stanley would have made for a fascinating subplot, which would give Stanley additional motivation for his goals as well as add complexity to the villains. This whole film is full of originality that's sadly left unexploited.
Ugly Cute: Pretty much the film's entire design aesthetic.
"Weird Al" Effect: The "I'm a Bad Troll" meme derives its melody directly from an old Russian folk song, "The Volga Boatmen".