!!Tropes for the movie

* BadassDecay: In-universe: the Missing Link apparently once held his own against the navy, the national guard and some baywatchers. [[spoiler:Until he beats up about thirty clones in hand-to-tentacle combat, that's ''very hard'' to believe.]]
** According to his website profile, he was a real badass. [[spoiler:Until 30 years ago. Probably out of his prime at that point.]]
*** Not to mention he's been cooped up in Area 52 for several decades. Note the beer belly.
**** In the TV series they seem to have had him working out in the interim. Not much more effective, but less beer belly.
* CargoShip: B.O.B./Green Jello. A match made in mixers.
* CrazyAwesome: General Warmonger.
* CrowningMusicOfAwesome: The orchestral cover of "[[Music/TheB52s Planet Claire]]'' that plays as the President prepares to make first contact.
* EnsembleDarkhorse: Oh, there's a LIST for this one.
** B.O.B. for the kids and the merchandise. Not really surprising he's the kid appeal character; he's the silliest looking monster, and the funniest character.
** Dr. Cockroach hit it off with fangirls.
*** Well he ''is'' [[GeekyTurnOn voiced by]] Creator/HughLaurie...
** And there's the president, where every moment involving him is one of the most hilarious things you'll ever see.
*** Well his voice actor was [[Series/TheColbertReport Steven Colbert]]
** Katie and Cuthbert, the OneSceneWonder role reversal teens who encounter the aliens early in the movie.
* InferredHolocaust: [[spoiler:In a post-credits scene, the President accidentally launches all of the nukes.]]
* ShipToShipCombat: The fandom is a bit split when it comes to who Susan gets paired with. Given the lack of TokenRomance within the film, many tend to gravitate towards Dr. Cockroach/Susan since he takes an active role in trying to reduce her size and they seem to converse the most (also, they're the only two monsters who used to be human). But Link/Susan has its share of fans as well, considering that Link's whole deal is that he chases beautiful babes anyway. God help you if you're on the fence...
** The whole ship-to-ship combat situation for this fandom is not ''that'' bad. There are at least fans who can tolerate both points of view on the matter no matter which side they're on (if they're even on one in the first place). There are plenty of fandoms that are much worse..
* ShoutOut: The whole plot premise could be considered a shout out to the ''Wizard of Oz'' movie. Think about it. A MacGuffin girl (Susan/Dorothy) taken out of her normal life and set on a quest to defeat a BigBad (Gallaxhar/the Wicked Witch) via clingy {{Phlebotinum}} (Ruby Slippers/Quantonium) with three male friends who double as a power trio (Link, Dr. Cockroach, B.O.B./Cowardly Lion, Scarecrow, Tin Man) plus a pet-like animal (Toto/Insectosaurus), is captured by the Big Bad so needs to be rescued by said friends who do so by pretending to be part of the Legions of Terror (complete in ''Monsters'' with B.O.B.'s almost direct "I may not have a brain but I have a plan" quote).
* UglyCute: Pretty much all of the other monsters aside from Susan herself.
* UncannyValley: The stylized inhuman "Monsters" are a bit easier to watch than the actual humans.
** To paraphrase the movie description at the top of the page, aside from the monsters, all the humans basically look like live action versions of the humans you'd see in mags like ''Cracked'' or ''Mad''. Kinda off-putting at first, but you get used to it.
* ViewerGenderConfusion: [[spoiler:Insectosaurus.]] The movie calls the monster [[spoiler:a "he"]], but a behind-the-scenes book lists [[spoiler:the monster as a female]]. This has lead to a BrokenBase amongst the fans of the movie as to which is truly canon regarding the monster's gender.
** [[spoiler:Considering the fact that Insectosaurus as a butterfly has [[TertiarySexualCharacteristics prominent eyelashes, lipstick-like markings and body curvature suggestive of either a cartoon bustline, a narrow waist or both,]] I would've thought the answer was pretty clear...]]
*** [[DudeLooksLikeAlady Not necessarily. Remember, in the animal kingdom, Pretty does NOT always equal female.]]
**** Also in the animal kingdom [[GenderBender sex is not always a fixed thing...]]
** If Insectosaurus was only a larva [[spoiler:before she metamorphosized]], then it may not have even ''had'' a gender or anatomical indicators thereof. Calling it "he", as with B.O.B., could've been [[ItIsDehumanizing purely a convenience]].
* WhatAnIdiot: Derek dumps Susan for the sake of his career without considering the worldwide fame their continued relationship would bring him, not to mention the millions of dollars in book deals and movie rights. Sure, he'd need a raincoat to have any hope of ever pleasing her, but it's still a very stupid decision from someone who's already been characterized as a selfish asshole. [[spoiler:He ''does'' put things together, sort of, when he forgives her and offers to take her back at the end. Of course mentioning that he was offered a network slot if he got an exclusive interview in the next sentence made Susan doubt his sincerity.]] Letting that detail slip only reinforced his stupidity.
-->'''Susan:''' Are the cameras running, sweetie?\\
'''Derek:''' Why, of course they are!\\
'''Viewers''' (''[[FacePalm facepalm]]'')
** According to the commentary, one possible (deleted) follow-up to Derek dumping Susan has her going on a rampage through town to try and crush Derek. It would have been somewhat out of [[ShrinkingViolet character]] for Susan to do this at this point of the movie, but that doesn't remove the fact that she ''could'' have done it, thus further reinforcing Derek's idiocy.
* TheWoobie: Susan. After Derek dumped her, she looked so much like a kicked puppy.
-->"I don't want a [[FauxtivationalPoster poster]]. I want a ''real'' kitten, hanging from a ''real'' tree."
** The monsters, after they scare off the party.
** Link. The poor guy gets his butt kicked ''several'' times during the battle against the robot probe, and even gets knocked out ''after it's already been defeated.'' He was so obviously downbeat about his performance that one almost expected him to do a FaceHeelTurn.

!!Tropes for the series

* DesignatedHero: Most of the time the titular monsters come across as idiotic xenophobic jerks, and there are several occasions where the conflict of an episode brought about by the monsters being assholes or just being plain stupid.
* HilariousInHindsight: The Internet (who is actually an alien) constantly uses old and dead memes. This would be a groan-inducing attempt at being [[WereStillRelevantDammit relevant]]...if not for the brief resurgence of extremely old memes at the time, making the episode look relevant ''and'' seem like a parody of current events.