Sci-fi has always been known for its incredible creature effects, but not all of them hit the mark. From the best of the best to the worst of the worst, let's take a look at what the genre can offer us. Luckily we have some real masters of special effects on this list, but that doesn't mean it won't be without its absolute atrocities. Either way, we're sure it'll be an entertaining read.

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Best: Frankenstein

Frankenstein as he's commonly known, or Frankenstein's monster as is more accurately titled, is one of the most sympathetic creatures sci-fi has ever seen. He was also created by a woman, who are generally underrepresented in the genre.

What makes Frankenstein's monster so realistic isn't necessarily his creature design in any specific incarnation, it's that he's a living, breathing example of the alienated human, consumed by existential angst like the rest of us. What's so realistic is the core of his being. He didn't ask to be created, to be a monstrosity, yet here he is, coming to terms with his being.

Worst: Trolls

Troll 2 goblins

The trolls, namely their incarnation in Troll 2, are simply terrible. Not only are they only referred to as goblins throughout the film, but they don't make the slightest bit of sense. They live in a town called Nilbog (surprise, it's goblin backwards) and they're vegetarians.

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Not scary when they're creatures that don't eat humans? Well, just you wait. They feed the humans who visit Nilbog their disgusting food, which in a very fairytale type way, seals their doom. It turns these humans into vegetable matter, which in turn allows the trolls to eat them. Convoluted? Yes. Yes, it is. That's not as bad as the fact that the trolls look less scary than Jim Henson puppets in Labyrinth either.

Best: The Terminator

Terminator 1984 movie poster

The Terminator in James Cameron's Terminator franchise is absolutely iconic. The look of the character is just as incredible as the many one-liners delivered by leading man Arnold Schwarzenegger.

He'll be back in pop culture again and again. Not only is the indestructible assassin terrifying, but the fact that advances are being made in A.I. and cybernetic science day after day makes him more realistic than we may like to admit. Don't be too frightened though. This doesn't mean he'll be asking for your clothes, your boots, or your motorcycle anytime soon.

Worst: Signs

King of the twist, M. Knight Shyamalan is here for the list with his 2003 Mel Gibson helmed film Signs. The aliens don't look bad at all. Honestly, the creature effects are more than capable; the issue is that their weakness is one of the most ridiculous and often-stated plot holes in all of cinema history.

These aliens, it's discovered, is water. Sorry to spoil the plot twist, but there's no way anyone would have guessed this considering they decided to try to colonize a planet that's over 70% water.

Best: The Fly

jeff goldblum as seth brundle checking his teeth

Jeff Goldblum's performance in David Cronenberg's The Fly is great. It shows the descent of a man into a pure inhuman animal. When a fly gets caught in a machine that Goldblum's character is using for a scientific experiment, his DNA begins to fuse with that of the little "bug" in his system.

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This is done in incredibly graphic detail, handled exceedingly well by Hollywood's very own master of body horror. If you're not afraid to be incredibly grossed out, give this one a watch. Be warned however, this one isn't for anyone with a weak stomach.

Worst: Sharknado

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Have you ever wanted a monster so terrifying, so plausible, so made up of pure evil that no one can resist its power? That monster is not in Sharknado. That's not discounting the fact that this is a joke movie.

That is understood; however, that doesn't mean that it looks good regardless. Not only is the monster a goofy amalgamation of two of the least scary horror-thriller elements, but it's completely ludicrous. There's no excuse for this movie or the completely unnecessary amount of sequels. It's probably best to avoid it all together.

Best: The Thing

The Thing by John Carpenter stars Kurt Russell

John Carpenter's creature effects are some of the coolest you'll ever see. When some scientists on a research project in Antarctica come into contact with an alien life-form that can mimic any living being it infects, there's no one to trust and nowhere to run.

The monster's true form is unknown, but that's even more frightening since the scientists have no clue who could be harboring it. That's not to say that it's not incredibly grotesque when it's onscreen though.

Worst: Godzilla

Godzilla and the rest of the Kaiju films are an absolute delight. There's really no arguing with that. This movie singlehandedly invented a genre and required a great deal of ingenuity and creativity to pull off. Unfortunately, even the best of latex costumes and miniature sets couldn't make this movie believable.

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Again to reiterate, this doesn't mean this film isn't a masterpiece, it just means that if you're looking for a special effects marvel, this isn't your best bet. If you're looking for a charming piece of post-war Japanese cinema though, you can't go wrong with any Kaiju film.

Best: Xenomorph

The Xenomorph from Ridley Scott's 1979 film Alien is an absolute marvel of creature design. The creative team decided to involve H.R. Giger, and despite the odd psychosexual nature of his previous work, their risk paid off in the form of a creature that's truly threatening to any form of life that it comes in contact with.

The Xenomorph's texture is glossy and black like latex, its spit and blood are corrosive like acid, and it has a smaller version inside of its mouth, which it uses to consume its prey. The Xenomorph is not a beast to be trifled with.

Worst: The Manitou

The Manitou

The Manitou, oh where to begin. While it might not be completely sci-fi, the biological body horror elements definitely lend themselves to being considered. Aside from that, just how zany this film is can't be understated. This film is laughably bad, although it received mixed reviews upon release. Along with the trolls in Troll 2, this monster makes up the duo of films in this list that are so bad they're good and must be seen to be believed.

The plot centers around a fetus growing inside of a woman, who will be the reincarnation of a dead shaman, returning to wreak havoc on her as revenge. This sounds scary, sure. But once you see the special effects in this film, you'll have no doubt about how it made this list.

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