Warning: As a Spoilered Rotten Ending Trope, EVERY SINGLE EXAMPLE on this list is a spoiler by default. You Have Been Warned.
Sudden Downer Endings in Western Animation.
- Adventure Time has two examples, both related to the Ice King:
- The infamous (within its fandom, at least) "Holly Jolly Secrets" Christmas Special. It is about the heroes Finn and Jake watching a bunch of videotapes made by their arch-enemy and Ineffectual Sympathetic Villain. The whole time, Finn and Jake continue because they believe the Ice King has hidden "evil secrets" in the tapes. Once the Ice King finds out that they are watching his tapes, he tries to stop them, but fails to prevent them from putting the last tape in their VCR. At that point, all he can do is watch in horror as Finn and Jake discover that he used to wear glasses, but more importantly, that he used to be a normal human being named Simon Petrikov who was driven insane and transformed by his crown, which was actually a supernatural artifact that he'd bought. They watch the young Ice King lose his mind and the woman he loved (who he called "princess" before she left him). Before this, the Ice King had almost always been a funny character, and plenty of things that were Played for Laughs in the past were made tragic by this revelation. While the series would continue to use the character for comic relief, this was held back on for a string of episodes following the reveal. In addition, the other tapes before the last one are usually the Ice King saying or doing hilarious things, but some of them show him sitting around his house, crying, although that still seems to be Played for Laughs.
- Ice King's past comes up again in "I Remember You", when it's revealed that Simon took care of Marceline when she was a child in the aftermath of the Mushroom War. The crown's magic allowed him to protect her from danger, but every time he used that magic, he started losing his mind, and came closer and closer to being irreversibly driven insane. At present, he doesn't remember her very well. It's later subverted when he temporarily becomes normal again and brings Betty Grof (his "princess") to the future. She swears that she'll find a way to reverse what the crown did to him, and the fact that he never lost her makes the revelation less tragic.
- The final episode of The Amazing World of Gumball was largely about a live-action antagonist trying to integrate the cartoon kids into the real world by turning them into humans, only to be thwarted by Gumball and Darwin. In the closing moments of the episode, the villain, who turned out to be recurring character Rob, laments that he was unable to explain that he was trying to save everyone from the Void, which begins to suck in all of Elmore at the very end.
- The final segment in the last episode of Animaniacs, "The Animaniacs Suite", is a musical Clip Show of the highlights of the show using the various Leitmotifs of the characters. The final shot is of Ralph, Dr. Scratchensniff, and Hello Nurse bringing a net down onto the Warners, presumably catching them and dragging them back off to the water tower now that the series is over.
- The 2020 reboot utilized this in its final segment (which was the safety segment) of its final episode as well, with the Warners becoming aware ofthe show's sudden cancellation and being abruptly killed by a meteor (which had been slowly falling up until this point) shortly afterwards while they think of what their last lines should be, transitioning to the "Stay safe, sweeties" card that ended each episode before it, ending the series.
- Parodied in BoJack Horseman with the in-universe family sitcom Horsin' Around. Thanks to BoJack's growing disillusionment with the show, it ultimately ended with his character dying and his adopted kids being sent off to foster care, while believing that their adoptive father died because they didn't appreciate him enough.
- Camp Lazlo: The ending of the last episode "Lumpus' Last Stand" reveals a humongous plot twist - Lumpus was never really the scoutmaster, he was a literally insane man who had locked the real scoutmaster away (Namely, an older version of Heffer from Rocko's Modern Life) presumably for the duration of the entire show, to steal his life. He is sent to an asylum. This twist is so dark and downright shocking that the entire cast except Lazlo can do nothing but stand in silence for a moment. Word of God claims that Jane Doe busted him out afterward and married him, but it's still an Ass Pull.
- "Chicken Little", from the Classic Disney Shorts plays like a normal Cat-and-Mouse cartoon...until the end, where despite the Narrator's assurance to the audience that everything turns out alright, Foxy Loxy catches and eats all the chickens, turkeys, and ducks, smiling smugly all the while.Narrator: Hey, wait a minute! This isn't right! That's not the way it ends in my book!Foxy Loxy, leaning against his "Psychology" book: Oh, yeah? Don't believe everything ya read, brother!
- In The Crumpets season 3 finale "Va te catcher vilain!", Caprice and Cassandra, who are substituting an injured Triceps in a televised wrestling match and wear a costume of her together, are beaten up by their gargantuan opponent. This is when the episode suddenly concludes, too, and this is very shocking for a season that is somewhat lighter than the earlier episodes.
- Drawn Together ends with one of the main characters dying a brutal, tragic death, and then reality itself being RetGoned due to Spanky's idiocy.
- The infamous Futurama episode Jurassic Bark shows one of the few positive things about Fry's life in the 20th century: the stray dog Seymour Asses who he befriended and adopted, and centers around him wanting to use the dog's remains to revive it. He ultimately comes to the conclusion that it would be wrong, since the dog lived its natural lifespan and probably forgot all about him. It seems like it's heading for a Bittersweet Ending as Fry decides to let his friend rest in peace...and then the credits sequence shows that Seymour waited the rest of his natural life in front of the pizza parlor for Fry to come back, not only because he loved his master that much, but also because Fry's last words to him were "stay here, I'll be right back". Initially made less depressing by the events of Bender's Big Score, in which a second Fry created via Timey-Wimey Ball is revealed to have taken care of Seymour all those years in the past...only for Bender to cause the parlor to collapse, fossilizing him.
- Gravity Falls:
- "Dreamscaperers" ends with Bill Cipher defeated, the deed to the Mystery Shack defended, and Dipper finally understanding Stan's treatment of him and bonding. Everyone lives happily ever after for about three seconds, whereupon Gideon blows open Stan's safe with dynamite, steals the deed, and begins demolishing the building, which continues in "Gideon Rises".
- "Dipper and Mabel Vs. the Future" ends with Mabel upset that Dipper is leaving her, taking the wrong backpack, and being tricked into handing the interdimensional rift to Bill Cipher, who breaks it and brings about The End of the World as We Know It, leading to the epic "Weirdmageddon" finale.
- Hilda: Season 2 ends with everyone safe home in their beds, and Hilda has finally patched up her relationship with her mother...only for the last minute of the episode to have Hilda turned into a troll and teleported far away from Trolberg.
- Kaeloo: As this is a Sadist Show, this has happened in many episodes:
- In Episode 118, when the Alpha Bitch Pretty posts humiliating pictures of Kaeloo, Stumpy, Quack Quack and Mr. Cat on social networking site "Fakebook", they get revenge on her, and then the fight escalates until the four of them use Disproportionate Retribution to punish her. At the end of the episode, they decide that they were too harsh and go to apologize and give her some presents, but before they can, they find out that she wrote a book revealing all of their embarrassing secrets and already published two million copies. They decide to leave without saying anything and accept that they'll never change her.
- In Episode 124, Kaeloo, Stumpy and Quack Quack play a new game that uses technology which requires an immense amount of concentration. The episode goes well and they have fun together, but at the very end of the episode, since Stumpy doesn't have much in the way of a brain, concentrating proves to be too much for him and he has to go to the hospital, and ends up flatliningnote . Of course, this being Kaeloo, nobody cares, but it still is pretty sad.
- In Episode 16, the episode has a generally funny plot, but at the end, Mr. Cat suggests kicking Kaeloo out of Smileyland and everyone else agrees.
- A pirate themed two-part episode had Olaf send the main four on a dangerous treasure hunt and promise that he would reward them if they found the treasure. They manage to find the treasure and get back to Olaf alive. Just as it looks like Olaf is about to reward them, Olaf suddenly leaves with both the treasure and the reward, revealing that the main four have been scammed.
- The classic Looney Tunes short "What's Opera, Doc?" is mostly a goofy parody of opera tropes combined with Bugs Bunny's typical slapstick and Attractive Bent-Gender gags, and ends with Elmer going into a rage and killing him. Bugs does break the fourth wall long enough to deliver the last line, though:"Well, what did ya expect in an opera—a happy ending?"
- The Russian animated short Mountain of Dinosaurs
portrays the Age of Dinosaurs as a Sugar Bowl, but ends with their extinction. - Pixel Pinkie: The last episode opens with an unusually sad narration from Nina's journal entry, foreshadowing Pixel Pinkie's departure from her life and states that she will never see her again. Pixel Pinkie divulges to Nina that genies only get a certain number of wishes and that Nina only has 19 more wishes left. After some escapades that led to most of the wishes being wasted, Nina and Anni give Pixel Pinkie a chance what she wishes for, which is for Nina and Anni to visit the digital genie world, and so Nina wishes it for her. Whilst making the most of their visit in Pixel Pinkie's world, the wish (as per usual) wears off and Nina and Anni are transported back to the real world, ending the episode and the series as a whole.
- ReBoot:
- The season 2 finale "Web World Wars" has the Sprites and Viruses team up to save Mainframe from destruction from Web Creatures. This is going well until Megabyte suddenly betrays Bob and shoots him into the Web. Mouse seals off Mainframe, realizing too late what had happened, and Megabyte turns his forces on the heroes, leading into the cliffhanger starting season 3.
- The episode "Game Over" looks like young Enzo will triumph over the User and save the day yet again... Until the User claws out his eye and defeats him in a Gory Discretion Shot, leading to the ominous "Game Over, User Wins" line and Dot breaking down with a Big "NO!" as Megabyte cackles evilly. The results of this downer ending are explored throughout the rest of the season.
- Rick and Morty:
- Played for Black Comedy as "Total Rickall" seems to end on a triumphant note as Beth shoots the final parasite, Mr. Poopybutthole...only for it to be revealed that he was actually real. The episode ends with Beth having a chillingly realistic nervous breakdown and the rest of the family panicking as they desperately try to save Mr. Poopybutthole. Although it ends up being a Sudden Bittersweet Ending, as the next episode reveals Mr. Poopybutthole survives, but is shown to need months of painful rehab in order to get back to functioning again, and having his nurse turn Beth away when she tries to visit him in the hospital.
- In the episode "Analyze Piss", Rick performs a Dead Person Impersonation of an Ineffectual Sympathetic Villain who was Driven to Suicide by Jerry with the intent of making it seem as though he died a hero. He ends up inadvertently convincing the family that he set the whole thing up to make Jerry feel better about himself, and the episode seems as though it's about to end on a high note... until Rick cracks and tells Morty the whole story, who then spitefully tells the rest of the family. The episode then ends with everyone bickering with Rick as Jerry crosses the Despair Event Horizon.
- The finale of Scary Larry has the band breaking up and all the members moving out of the house.
- If any episode of The Simpsons has any character change in a positive way or gain something nice, and they keep it near the end of the episode — expect it be suddenly yanked away soon afterward. The Status Quo must be preserved. That being said, there were only a few notable exceptions: Barney recovering from his alcoholism (although the writers eventually undid this), Lisa telling Homer that she'll never be happy with her body image (though the whole thing about Lisa being insecure with her body hasn't been mentioned since that episode), and Milhouse's parents staying divorced (though they did get remarried in "Little Orphan Millie").
- In Sir Billi, after roughly 80 minutes of mood whiplash and inappropriate sexuality, the movie ends relatively happily. And then the credits suddenly show a flashback montage of Sir Billi's life, one blatantly lifted from the opening of Up - complete with the death of Billi's wife.
- The Snowman, which remains upbeat until the final moments, which reveals first that the Snowman has melted and died, then that it definitely wasn't a dream, and the main character breaks down and cries. Supposedly this was to teach viewers about treasuring time with loved ones because of how these things don't last, but that still makes the ending a downer and a gut punch.
- Der Schneemann ("The Snowman") is a 1944 German cartoon that basically has the exact same ending. A snowman that comes to life sees a picture of summer in July and decides to wait in an icebox until July comes so he can enjoy summer. One might expect, given the light, whimsical tone of the cartoon, that the snowman would eventually go back to his icebox, or somehow escape his fate, but he still melts at the end.
- Star Trek: Lower Decks season two ends with the crew of the Cerritos saving the crew of the Archimedes, Captain Freeman performing her first First Contact and ultimately deciding to forego her promotion to captain of another ship — only for a group of Starfleet personnel to arrest Freeman under the assumption that she caused the destruction of Pakled Planet and conspired with Klingon extremists to do so.
- Tangled: The Series:
- The second season ends with Rapunzel about to get the Moonstone...until Cassandra snatches it and bonds with its power, changing her appearance and turning into a demonic monster, her hair light blue. Long story short, Cassandra betrays Rapunzel and Eugene, telling them to "be careful of who to trust!" as they look in horror. Cue Fade to Black and credits. In the next episode "Rapunzel's Return", Cass reveals she did this because her mother, Gothel, abandoned her in favor of Rapunzel and always lived in her shadow, thus she claimed Rapunzel's destiny as her own.
- The penultimate episode "Once a Handmaiden..." ends with Cass declaring herself a bad guy and unleashing the true power of the black rocks, seizing full control over Corona, leading into the Grand Finale.
- Teenage Mutant Ninja Turtles (2012): The Show Within a Show Grognar The Barbarian ends with Grognar being eaten by a dragon, much to the disappointment of the Turtles. This serves as foreshadowing for the season finale, when the Tricereton armada arrives. The season ends with Shredder choosing to kill Splinter than to save Earth, and the Earth destroyed by the Triceretons' singularity weapon. The Turtles are miraculously able to fix everything thanks to some time traveling, but it is still a serious downer until then.
