* {{Anvilicious}}: Possibly the preachiest monster movie ever made. Not only the GreenAesop about pollution but abortion, urban squalor, Indian rights and corporate greed are all invoked at various points.
* HilariousInHindsight: A certain pair; [[Creator/TreyParkerAndMattStone Mr. Stone and Mr. Parker]], must have seen this film because Katahdin looks very familiar to Manbearpig. Or maybe it has an animated cousin.
* {{Narm}}:
** [[https://www.youtube.com/watch?v=7zLb9UtQhy8&feature=player_embedded#! The exploding sleeping bag!]]
** Likewise, the sudden attacks by various mercury-crazed animals earlier in the film (most notably the fireplace raccoon) are more likely to provoke guffaws than terror.
** The overblown creepy music when we first see the paper mill almost sounds like a parody.
* NauseaFuel: Katahdin was so absolutely revolting it had people puking in the theaters.
* RetroactiveRecognition: The late Creator/KevinPeterHall, later to be better known as [[Film/ThePredator the Predator]] and [[Film/HarryAndTheHendersons Harry]] was inside the Katahdin suit.
* SoBadItsGood: In his book about the horror genre, ''Danse Macabre'', Creator/StephenKing cited this film as a prime example of an enjoyably bad movie (he admitted to watching it three times).
* SpecialEffectsFailure: Katahdin looks good in certain closeups and distant shots. More direct shots, however, are about as convincing as a ''Franchise/PowerRangers'' monster.

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