35 Best Cartoon Monsters Ever, Ranked

Cartoons are filled with all sorts of monstrous creatures. Even the ones intended for kids!  Actually, if to judge by the number of monster cartoons in films and animated series, monsters are one of the best ways to represent evil or destruction. For me, a cartoon monster is a giant mindless creature with razor-sharp claws, huge fangs, crooked horns, and preferably tentacles. However, there are many other types of monsters in cartoon land, and on this list, I will pick the 35 top cartoon monsters. So, prepare yourselves. This is going to be monstrous.

35. The Tar Monster from Scooby-Doo

The Tar Monster cartoon monster

One of the best cartoon monsters, The Tar Monster appeared in “The Tar Monster “episode in season 3 of Scooby-Doo, Where Are You! Show. He is practically a green-eyed Cyclops made of simulated tar that has the ability to produce fluid tar out of his body. Because of his special physique, The Tart monster can envelop his victims in his fluid tar body and either constrict or suffocates them. The really weird part in the episode was when Scooby pretends to be a photographer and invites the Tar Monster into his studio for pictures. The weirder part was that Tarster actually accepted the offer! I remembered the show was really illogical at times, but this was downright bizarre.

34. Muchi from Star Wars: The Bad Batch

Muchi cartoon monster

A female baby Rancor, Muchi once belonged to gangster Jabba the Hut. However, she was kidnaped by Zygerrian slavers to the planet Ord Mantell. Clone Force 99 was hired to return Muchi to Jabba and managed to complete the job. Although an adolescent Rancor, Muchi was already roughly 1.82 meters tall and a formidable opponent who fought until she was exhausted and passive. This Star Wars creature even exchanges blows with Wrecker, who is the muscle of the mercenary unit, and puts up a good fight.

33. Marshmallow From Frozen

Marshmallow cartoon monster

A Disney cartoon monster, and probably one of the most famous monsters on this list, Marshmellow is a giant snow monster. He was created by Elsa to force Anna and Kristoff to leave her ice palace. Later, he served Elsa to keep out other unwanted visitors like Prince Hans and Duke’s Thugs. As shown in Frozen, this giant snowman possesses vast strength that allowed him to easily uprooted a big tree and throw it a great distance. He is also highly durable, and able to take spears and arrows without sustaining damage. When angered, Marshmallow’s eyes glow blue, and he can cause icicles to burst forth from his body in many forms, such as horns and teeth. In this augmented state, Marshmallow seems invincible.

32. Ickis, Krumm, and Oblina from Aaahh!!! Real Monsters

Ickis, Krumm, and Oblin: cartoon monster

Ickis, Krumm, and Oblina are three young monsters who attend The Monster Academy, where they learn how to scare humans. Each one of the three friends has his methods of scaring humans. For example, Ickis can grow bigger, while Krumm is so filthy and outrageously smelly that he can make humans scream without lifting a finger. As for Oblina, her favorite method of scaring people is to reach within herself and pull out her internal skinny organs. IMO, her technique is the best, plus she has considerable talent for shapeshifting into various terrifying forms.

31. Gargoyle from Inhumanoids

Gargoyle cartoon monster

When Gargoyle first hatched from his egg, the first thing he did was start murdering and eating the rest of the hatchings. Yeah, we got to see him in the episode rip the arm off one of his next-mates and eat it! He is that horrific. Gargoyle has a giant tooth-filled jaw, a single eye, and an exposed digestive system. This guy constantly wants to eat everything he sees. You got to love him for that. He is also very powerful and fought on par with Metlar, who is the main antagonist of the Inhumanoids cartoon show. He only lost due to getting distracted.

30. Swamp Beast from Monster in my Pocket: The Big Scream

Swamp Beast cartoon monster

One of the main three antagonists for the animated TV special “Monster in My Pocket: The Big Scream”, Swamp Beast escaped incarceration on Monster Mountain, where the evil monsters are imprisoned. Swamp Beast is a large, mulchy brown creature without legs. Swamp Beast seems to be inspired by the DC Comics character Swamp Thing and the similar Marvel Comics character Man-Thing. His habitat is, of course, swamps and marshes around the globe, and dwells in bottomless pits. He usually feeds on rodents and gators, but will happily eat a human.

29. Cthulhu Monster from Rick and Morty

Cthulhu cartoon monster

Although Cthulhu never appeared in an actual Rick and Morty episode, he appears in every season’s intro. In the intro, he always chases Rick and Morty, trying to hurt them. Cthulhu has the head of an Octopus with six eyes, huge wings that let it fly, and a sort of dragon tail. Cthulhu may be a female, as in one season it tries to protect its child. However, I know some dads who will also try to protect their children from Rick, so it doesn’t prove anything.

See also: 31 Toughest Characters With Eye Patches

28. Pizza Monster from Teenage Mutant Ninja Turtles

Pizza Monster cartoon monster

Appearing in the episode “The Case of the Killer Pizzas”, Pizza Monsters are creatures from Dimension X that are born from meatball-like eggs. Three of the Pizza Monster eggs were brought from the alternate Dimension by Krang and given to Shredder to destroy the NinjaTurtles. As you can probably tell, the Pizza Monsters kind of resemble the Xenomorphs from the Alien franchise. However, the Pizza Monsters are yellow.

27. Inter-Dimensional Monster from Dexter’s Laboratory

Inter-Dimensional cartoon monster

The Inter-Dimensional Monster is a giant monster that was summoned by Dexter from an alternate dimension, using his untested Inter-Dimensional Doorway. The monster came from the other side of the doorway and immediately destroyed Dexter’s lab. Dexter fought it but was unable to defeat it and was swallowed whole by it. Dexter managed to write a note to himself saying not to turn on the doorway but ended up creating a time paradox. I could never figure out how, but later episodes show Dexter alive and well, so I guess he later somehow found a way to save himself. If any of you understood what happened, I would appreciate it if you’d send me a message.

26. Tentakill from Street Sharks

Inter-Dimensional cartoon monster

This biped mutant creature was designed by Dr. Paradigm as a weapon, aimed to kill Sir Bolton to finally stop the line of the Street Sharks. First appearing in Sir Shark-a-Lot episode, Tentakill is incapable of speech, shows limited intelligence, and was not used often by Dr. Paradigm. Truthfully, I don’t know what Tentakill is supposed to be, but it never stopped me from liking him anyway. He is such a weird-looking monster! Also, is that a rocket launcher on the left side of his body?

25. Exo-Skin from My Life As a Teenage Robot

Exo-Skin cartoon monster

Originally, the Exo-Skin was supposed to be a suit used to make robots appear as “normal human people”, and help Jenny fit in amongst the other teens. However, the Exo-Skin is evil and has developed a mind of its own. It became alive and sneaked itself on Jenny while she was asleep. It then tried to force its will on Jenny, nearly taking over her soul and discouraging her from being her true self. The Exo-Skin is a true monster!

See also: Top 35 Best Cartoon Robots Of All Time, Ranked

24. The Monster from SpongeBob SquarePants

The Monster from SpongeBob cartoon monster

In the episode “Mutiny on the Krusty”, the monster, who is a sea monster, is the main antagonist of the episode. It attacks everyone in the Krusty Krab and eats Squidward. Only when Mr. Krabs decides to fight the monster that the monster spits Squidward out. I like this monster design, with its six yellow eyes, six tentacles, and spikes on its back.

23. The Goozim from Phineas and Ferb

The Goozim cartoon monster

Goozims are large, hairy, flesh-eating, rectangular creatures native to Drusselstein, a Germanic country in which Dr. Heinz Doofenshmirtz was born. There’s a game in Drusselstein called “Poke the Goozim with a Stick”, in which a Goozim is locked up and poked by civilians. However, It’s unknown how one wins this game. A Goozim is about the size of a two-car garage. It is known that there are Goozims also in the 2nd Dimension, not just the 1st dimension.

22. The Creature from The Real Ghostbusters

The Creature cartoon monster

Now, that’s my kind of cartoon monster! What could be more monstrous than a giant amorphous mass of tentacles, eyes, and mouths? In the episode Ain’t NASA-Sarily So, this extraterrestrial creature invaded a space station and immediately started feeding on its power sources. The Ghostbusters had to use four different ghost traps to completely capture it. Technically, according to Egon Spengler, The Creature was not a real ghost, just some kind of Space monster. Nonetheless, the Ghostbusters had to contain him because it was still extremely dangerous, and unaware of how his actions were affecting others.

21. The Lich from Adventure Time

The Lich cartoon monster

The main villain of the Cartoon Network series, The Lich is a cosmic cartoon monster with many powers and abilities. He is an immortal who is over 1,000 years old and is said to have died and rot surrounding him at all times. His very presence is deadly to people and animals. The Lich is what monsters dread to find beneath the bed. The worst thing about him is that he always comes back. He survived having his skull ripped apart. Twice. He has fallen into the sun and been wished to be non-existent. What can possibly stop him?

See also: Best 12 Vampire Cartoons Ever

20. The Shape Shifter from Gravity Falls

The Shape Shifter cartoon monster

Aka Experiment #210, this monster appears in the Gravity Falls episode “Into the Bunker”. Not only that this creature can take the shape of anything that it sees, but it can also become a surreal combination of forms. Its default form is a white slimy body with four slender legs and pink eyes and a nose with four teeth hanging on the outside of its mouth. Dipper, Mabel, Soos, and Wendy found it in a bunker, and it immediately set up an elaborate scam to win their trust in its attempt to escape into the outside world. Clever!

19. Blorgulax from Futurama

Blorgulax cartoon monster

First appearing in the “Murder on the Planet Express”, Blorgulax is a shape-shifting extraterrestrial from an unknown planet. In this episode, Dan McMasters picks up a hitchhiker in space who turns out to be a human-eating monster who devours McMasters. The crew tries to keep away from the murderous alien and restart the ship, while the monster starts eating everybody on the Planet Express ship. However, eventually, it is revealed that no one died because of the Blorgulax. Well, except Dan who was mistakenly disintegrated by Bender and Fry!

18. Dark-ness Monster from The Smurfs

Dark-ness Monster cartoon monster

The Dark Ness Monster lives in a pool of chocolate in the Dark Ness Cavern, frightening away any who tries to taste from the pool. In the “The Dark Ness Monster” episode, Brainy and Clumsy go to the cavern to try and collect buckets of chocolate. They end up waking up the monster and losing Brainy’s glasses in the pool. Later, they find out that the monster was now wearing the glasses and had scared away his visitors because he was unable to see. The Dark Ness Monster gets to keep Brainy’s glasses in exchange for a bucket of chocolate.

17. Aku from Samurai Jack

Aku cartoon monster

Born from the Black Mass of Darkness in the depths of space, Aku is a powerful monstrous demon who uses dark magic such as necromancy and object materialization. Although he is pure evil incarnate, he does serve as comic relief at times, which makes him a bit less menacing.

16. The Hydra from Hercules

The Hydra cartoon monster

One of the best cartoon monsters, the Hydra is a giant, multi-headed dragon, and the first monster Hades sends to kill Hercules. Besides her size and strength, Hydra’s heads grow back when cut off. When one head gets beheaded, three more grow to replace it, making the monster unbelievably hard to kill. However, eventually, Hercules managed to defeat it, earning him fame from the citizens of Thebes. How? Well, it takes an entire collapsing cliff face to finally do the great monster in.

15. Mossland Monster from ThunderCats

Mossland Monster cartoon monster

Living in the unexplored territory of the Mosslands, the Mossland Monster is a gigantic cartoon monster that attacks anyone who dares to enter its territory. Despite its massive size, the Mossland Monster can disappear into the surrounding moss and remain unseen. However, even when he is invisible, he can see others. Besides this power, it is capable of shooting beams from its eyes that turn anything they touch into moss. The creature also can regenerate cut-off limbs, making it a nightmare to fight.

14. Sulley from Monsters, Inc.

Sulle cartoon monster

Sulley is a famous Scarer at Monsters, Inc. Company, where he works together with his companion Mike Wazowski. When Boo, a human girl, finds her way into the monster world, Sulley becomes her guardian and tries to return her to the human world. Sulley is a huge monster, with curved horns, razor-sharp fangs, and spikes that run down his backside to the end of his long dinosaur-like tail. All of these should have made him a scary monster. However, he is too fluffy to be frightening.

13. Space Mutant from the Simpsons

Space Mutant cartoon monster

He is an alien being whose sole purpose is to feed on the Earth’s populace. A shape-shifter, the Space Mutant can disguise himself as a human to attack other humans. In the “Principal Charming” episode, the Space Mutant is seen attacking a couple that is about to make love. According to some sources, the Space Mutant will attack other beings as well, but will not swallow them whole, as it does with humans. The alien has three eyes, four tentacle-like arms, and four teeth.

12. Serpentor from GI Joe

Serpentor cartoon monster

In the Arise, Serpentor, Arise! Miniseries, Dr. Mindbender decides to create a new COBRA leader to replace Cobra Commander, who fails too much in his opinion. Using the DNA of Sgt. Slaughter, Dr. Mindbender tries to cook up the next emperor, called “Serpentor”. However, Cobra Commander sabotages Dr. Mindbender’s attempt to create Serpentor, and the experiment results in the initial “Serpentor” creation being a blobby monster. This violent cartoon monster looks a bit like Marvel Comics’ Thing with all the rocky lumps, but it’s still very cool in my opinion.

11. Monster Krumholtz from Robot and Monster

Monster Krumholtz 
cartoon monster

The deuteragonist of the Nickelodeon Robot and Monster show, Monster Krumholtz is a carefree and happy individual who likes to help others with their problems and cheer them on. His best friend is a Mechanical named Robot who works with him in the Blinking Light Factory. As you probably noticed, I don’t like nice monsters, but I felt I couldn’t keep Monster Krumholtz out of this list.

10. Giant Red Monster from Fairly Odd Parents

Giant Red cartoon monster

Full name The Gigantic Monster That Won’t Go Away Until Timmy Tells The Truth About Chompy, the Giant Red cartoon Monster is a red Kaiju that towers over the buildings of Dimmsdale City. In Dream Goat! In the episode, the Giant Red Monster appears after Timmy wishes for the Gigantic Monster That Won’t Go Away Until Timmy Tells The Truth About Chompy. The monster has two curled horns, two sets of arms, and razor-sharp teeth as well as pointed claws. Now, that’s my kind of monster.

9. Bizarro Santa from Space Ghost Coast to Coast

Bizarro Santa cartoon monster

In the 73rd episode of Space Ghost Coast to Coast, called “Girl Hair” we get to see a monstrous evil Santa Claus who wanted to steal children’s teeth! Bizarro Santa has multiple eyes on his butt, a weird pink tail, and sharp fangs. He seems to walk on some kind of insect leg and to have a hideous extra side header.

8. El Chupanibre from Futurama

El Chupanibre cartoon monster

A giant sewer monster El Chupanibre is the kind of lizard who eats humans and even crocodiles. He has enormous yellow teeth, claws, and bloodshot eyes. El Chupacabra used to terrorize the mutants below New New York. However, he was finally flushed down the colossal toilet to the sub-sewer by Bender while saving Nibbler from getting eaten by the monster. El Chupacabra is a reference to El Chupacabra, the goat-sucking being of Mexican mythology.

7. Cobra Jafar from Aladdin

Cobra Jafar cartoon monster

Probably the biggest moment from Disney’s 1992 Aladdin, is when Jafar turns into this giant snake monster. I mean, that was out-and-out terrifying! Cobra Jafar is a giant cobra serpent with red eyes and red stripes on his back. The monster had Aladdin in his grip and nearly squeezed him to death when Aladdin fooled him into wishing to be a genie. Cobra Jafar was very powerful and managed to recover quickly when Aladdin stabbed him with his sword.

6. Snipe from Ren and Stimpy

Snipe cartoon monster

In the episode “Eat My Cookies” of The Ren & Stimpy series we get to see a multi-eyed creature that belongs to the Snipe species. The story is that Ren and Stimpy become girl scouts and earn merit badges. Stimpy goes after the Snipe-hunting-badge, which Ren refuses to believe is real. Surprisingly, Stimpy catches a Snipe that beats Ren pretty badly and earns the renowned Snipe Badge.

5. HIM from Power Puff Girls

HIM cartoon monster

HIM from Powerpuff Girls is one of the scariest monsters out there, but also one of the comedic ones. A devil or demon of sorts, HIM is the most powerful enemy the girls had faced. However, he rather takes down the trio by scaring or driving them apart than using brute force. HIM’s true form only comes out in the episode “Speed Demon “and it’s a whole new level of terror! In this episode, he grows bigger and more muscular than ever before to become a powerful monster nearly a hundred times the size he normally is.

4. The Sleeping Beast from He-Man and the Masters of the Universe

The Sleeping Beast cartoon monster

Probably the creepiest-looking monster to ever appear in the He-Man series, the Sleeping Beast is all I wanted in a monster: green skin, huge jaws, tendrils, a gaping mouth, and a yellow eye that extends out from its head. My only problem with it is that it only appeared once in the show, in “House of Shokti Part 2”. In the episode, it came from, a pool deep within the House of Darkness and tried to blast a kid who swiped He-Man’s sword.  He-Man threw a giant statue at it, and the beast sank back into the murky depths. Too bad!

3. Te Ka from Moana

Te Ka cartoon monster

She is a giant lava monster who serves as the guardian of Te Fiti, the island goddess and creator of all life in the Polynesian Triangle. After Maui steals her heart to give to humans, she becomes enraged and sets out to destroy everything in her path. In terms of design, Te Ka was inspired by several different elements. The directors wanted her to be both scary and beautiful, so they took inspiration from real-life volcanoes as well as traditional Hawaiian mythology. Her fiery appearance is meant to represent the destructive power of nature, while also paying homage to Pele, the Hawaiian goddess of fire. Although she is initially presented as a fearsome creature, it is later revealed that Te Ka is protecting Te Fiti out of love. When Moana finally returns the heart to its rightful owner, Te Ka calms down and returns to her true form: a beautiful woman.

2. Chernabog from Fantasia

Chernabog cartoon monster

Chernabog is a cartoon monster who made his first appearance in the Fantasia movie. He is a large, black, winged demon-monster who is seen on top of a bald mountain, summoning evil spirits. Chernabog is considered to be one of the most powerful and evil creatures in the Disney universe. Chernabog is menacing to behold, you start wondering why everyone considers Disney so kid-friendly!

1. Doomsday from Justice League Animated Series

Doomsday cartoon monster

My number one pick for this list, and perhaps the most famous cartoon monster, is Doomsday. I mean, he is the monster who killed Superman! Doomsday is a being of pure hatred and destruction and will stop at nothing to achieve his goals. He is one of the most feared beings in the universe, has taken on some of the greatest heroes in the DC Universe, and has always emerged victorious.

That’s it for this time. I hope you enjoyed this article as I did writing it! Did I leave anyone out? Please let me know.

A musician and film buff. I'm a Film graduate of The Sam Spiegel Film and T.V. School program. Creative writing by nature, a very curious girl, exploring all geek fandom.