Cosmic Horror Story / Western Animation

• Adventure Time packs one of these into a single episode in "Everything's Jake". Magic Man ^note the Nyarlathothep hijacks Jake's shapeshifting powers, turning his body into its own (historied) world (despite having not existed for more than a few seconds in the real world) ^note making Jake an unwitting Azathoth or Demiurge. Jake wakes up trapped inside himself and thinks it's awesome... until he discovers that he's hungry and he can't eat the food there because its made of his own flesh. Jake's hunger begins to cause earthquakes, but one one of the city's scientists correctly realizes that if Jake "leaves", their world will end. Said scientist tries to Take a Third Option by leaving Jake's world to find him some food, but upon emerging into the "glob world" (the Treehouse), he learns that the resident "glob" is a hideous Cthulhu expy ^noteFinn with a mouthful of spaghetti. The scientist melts at the horror of the sight, bemoaning the Awful Truth of their doomed world and the nightmarish beings they've worshiped. Sadly, Jake learns when he leaves that the scientist was right — leaving the city causes its citizens to revert back to being non-sentient parts of his own body, erasing them from existence. No one but Jake and Magic Man knows they ever existed and no one but Jake cares]].
• Despite being a comedy, The Amazing World of Gumball is gradually revealed to have shades of this. Often having to do with their world being sentient and running the "meta" elements that go into a TV show. If a character tries too hard to break out of their role in the story, the very universe can come apart, as seen in "The Job" and "The Test". Reality can also glitch out as seen in "The Signal", the rules of the world are pretty malleable in general, and the universe can seemingly directly manipulate things around the characters when there's a danger of them doing or realizing something that break the status quo, such as in the aforementioned "The Signal", where when Gumball and Darwin start to realize what's going on, only for the show to do a hard cut to them back at home with their family for a blatantly forced "Everybody Laughs" Ending (with the duo laughing along nervously) and when they start to go through puberty "The Kids", they learn they are Not Allowed to Grow Up. And possibly most disturbingly of all, in "The Void", we learn that characters (among other things) that universe decides were a "mistake" can just be spirited away to the titular void and (nearly) all memory and traces of their existence erased. And those of are just some of the major instances of forces outside of the characters' control messing with them. Oh yeah, and that void? The series ends on a Bolivian Army Ending (currently due to be picked up with an upcoming movie and new series) of the void opening up to suck up the the whole world.
• Interestingly, American Dad! features an example with "Rabbit Ears". After securing an old television, Stan encounters Nighthawks Hideaway, a black-and-white talk show hosted by the charismatic Alistair Covax. There's only one episode, which airs when Stan is all alone, and no records of its existence, outside notes made by loners like Tuttle concerning the subtle changes in the background casting. Stan finds Tuttle among the extras, and that the static from Tuttle's old TV creates a portal into the show. Covax is revealed to be a Faux Affably Evil Humanoid Abomination that entraps his viewers to serve as extras in an endless loop that gradually erases their memories. Anyone who strays or upsets him risks getting Eaten Alive when the world darkens for a "commercial". Stan and Tuttle's initial escape only leads them right back to the set. Stan resorts to smashing the walls to expose the static and barely escapes with Tuttle out of the TV. However, much to Stan's horror, his family drones about the jazz and stereo system Covax repeatedly promoted. Covax then transcends the fourth wall to wish the viewer a good evening, having taken over Stan's reality and leaving him to despair.
  • "Echoes" follows Steve's work study under local weatherman Memphis Stormfront, who is oddly obsessed with and warns Steve against using The Doppler on top of the station. After checking out The Doppler for himself, Steve is granted visions of the future, which become increasingly apocalyptic scenes of the world ravaged by a reptilian abomination called The Nameless One. Steve teams up with Memphis to destroy The Doppler, under the belief that it's waking The Nameless One. However, The Doppler was the only thing suppressing the beast, something Memphis planned the whole time. The Nameless One emerges from the earth, devastates Langley Falls, and traps the Smiths as they try to escape. Just to hammer it home, the hopeless scene transitions to the vast depths of space, showing Earth as just a speck soon to be obliterated. Unlike "Rabbit Ears" above, though, the dire ending is only a vision of a possible future, cut off by Steve choosing to shadow Buckle's urology clinic instead.
• Final Space is essentially just one chapter in an eons long cosmic horror story; the Big Bad is a being of pure evil and darkness called Invictus, who is imprisoned in the titular Final Space. It is attacking every timeline simultaneously, and in every timeline so far, it successfully conquered the universe. It corrupted a race of world-destroying Titans to do it's bidding which it unleashes on conquered timelines to wipe them out. It can possess any being with minimal effort and there is almost no way to get free once this happens, as Fighting from the Inside doesn't work. Dying will not save you from it, as it can resurrect and possess you even if you die outside of Final Space, and no, it doesn't possess your empty corpse, it revives you complete with your memories and personality and then possesses you, so killing yourself won't help. In the timeline the show focuses on, every attempt to fight back against Invictus is in vain as it once again escapes Final Space, and it's hard to imagine it ever being stopped.
• Futurama sets this up in The Beast With a Billion Backs, in which a horrifying, tentacled Genius Loci attacks our universe from its own after successfully making a way through it. Regardless of how you perceive Yivo after the fact, the motives are still pretty horrifying.
• The short-lived 80's Cartoon Show Inhumanoids was heavily influenced by the writings of H.P. Lovecraft. It pushed towards this trope as hard as was possible for a Merchandise-Driven cartoon from The '80s; even the comedy episodes had more than their share of horrors. One can only imagine how they would have upped the ante had it been successful enough to get more than one season (and toy wave)...
• Invader Zim has this in the form of "Halloween Spectacular of Spooky Doom". Zim thinks the kids at Skool are monsters, while Dib is progressively seeing horrible hallucinations from "beyond the veil" that eventually get him committed to an insane asylum in the "Nightmare Realm" from beyond reality that he is seeing into. Zim and Dib reluctantly team up, leading to both being trapped in the twisted world, and are separated when Zim is kidnapped and Dib goes to his house and is confronted with nightmarish versions of Gaz and Membrane who look like terrifying Humanoid Abominations. Zim meets Nightmare Bitters, the leader of the monstrous nightmare race, who wants to capture Dib and enter his mind to take over the world. The two eventually force their way back through the portal in Dib's head in the real world, and when she tries to follow them through Nightmare Bitters sees an extremely fat GIR devouring candy, a sight which is horrible enough that even she, an Eldritch Abomination, retreats at the sanity-destroying sight of.
• Justice League has a modified version of the Twilight Zone episode listed in the Live-Action TV sub-page. The seemingly idyllic town and quaint superhero team are all creations of their sidekick, who keeps the illusion and the very few real people under ironclad control with powers gained from a nuclear explosion. Becomes Lovecraft Lite when the superhero illusions fight back against their creator to help the protagonists, knowing if they win, they'll be wiped from existence because their real counterparts are already dead.
• Love, Death & Robots:
  • "Beyond the Aquila Rift" is a glorious example. It follows a space traveler who ends up stranded in a space station at the very far reaches of known space with his Old Flame Greta. Which is only half true: He is trapped at the far reaches of space, but in the hive of a terrifying spider-like alien creature, and everything he has seen is a psychic illusion the spider projects into his mind. Then again, the alien is a Benevolent Abomination doing it as an act of mercy so he doesn't realize the real horror of his situation; when he finds out what she really is, she just wipes his memory and puts him through the illusion again.
  • "In Vaulted Halls Entombed" is even more of an example. A group of American soldiers pursuing Taliban hostage-takers end up in a cave containing swarms of horrible flesh-eating spider-like monsters that gruesomely pick off both groups one by one, only for them to discover that the cave leads to a colossal temple-like underground prison containing a gigantic Eldritch Abomination whose very presence gradually whittles down the sanity of/enthralls human onlookers, and that will destroy the world if it's unleashed; the ending is ambiguous, but not reassuring at all.
• Mighty Max. Although over the course of the series we find Max beating his fair share of enemies, ultimately the great Big Bad is shown to be unstoppably powerful, and our hero's only hope to even tie with him is to let all his friends die and restart the timeline with his own death in the hopes it goes better the second time. Unfortunately, given the prophecies frequently referenced, this cycle has happened at least several dozen times.
• The main concept of the short (and potential series) Pibby is that various otherwise cheery and optimistic cartoon worlds, including many beloved classics (or expies of said classics) are being corrupted and devoured one by one by a horrific, nigh-unstoppable Glitch Entity that no one knows the origin of.
• Quoth the Nightmare Fuel page of Rick and Morty:
  [The show] is basically an exercise in existential horror: you are just one of a near-infinite number of yourselves, spread over a vast, uncaring, Godless multiverse. Some of you have died gruesomely and unremembered, others are wealthier and more successful than you will ever be. The fact that you are where you are isn't even down to luck; it just is. Entire civilizations live or die at the whim of callous, Lovecraftian gods, who may even be you, whether you know it or not. There is no meaning to life, no purpose, no destiny. At one point, Morty outlines this reality to his sister, and then, as an antidote tells her to come and watch TV, which is either the most nihilistic cry of despair ever screamed from that medium or the most audacious act of native advertising in television history.
• The premise of Samurai Jack is that a nigh-unstoppable, endlessly malevolent force of literal evil (the Start of Darkness episodes reveal that Aku is simply a tiny fragment of a creature that formed in the first moments of the universe) has conquered the world and is spreading his influence throughout the stars, and that a lone samurai warrior wielding a magic sword, one of the only things in existence that can even harm this force of evil, embarks on a seemingly hopeless quest to defeat the evil and Set Right What Once Went Wrong. Though after several decades of failure, Jack eventually succeeds at going back in time to kill Aku and ensure a far better future for the world, which firmly sets this as Lovecraft Lite.
• The premise of Shadow Raiders is that the 4 elemental worlds must band together using ancient technology to fight a great giant planet that wants to eat their homes. It is unstoppable, unrelenting, and unbeatable. The only hope is to run away, or face certain destruction. And they can't run forever. For a child's show this is somewhat jarring.

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