Okay, so you've just gotten into a brawl with your local Eldritch Abomination, just after you deliver the Knockout Punch against him. Apparently as a final "screw you," something bad happens to you, or the world you live in, in such a way there is almost no way to solve that problem that will be done without sacrifice.
Congratulations, you just broke your arm punching out Cthulhu.
This trope is called upon as a way of showing the true futility of trying to stop the physical or literal manifestation of an all-powerful being. It really doesn't matter if you have powerful mythical weapons or giant galaxy destroying guns; the physical form of him is irrelevant to his powers to utterly smack you aside with merely a nod. It just can't really be done. Eldritch Abominations such as the namer of the trope himself do not feel much pain from being punched out, since all you did was merely destroy his physical manifestation, and punching him out will only delay your demise as you:
Puella Magi Madoka Magica: Slow-acting, but inevitable.. If you gain the power to fight Witches, you will become a Witch. Played straight in one timeline, to world-ending proportions, averted in another Mercy Kill, and invoked in a third. This trope is the driving reason for the plot of Homura's entire story arc.
In perhaps a literal example, in Rurouni Kenshin, Sanosuke punches Shishio so hard that he shatters all the bones in his hands. Shishio is temporarily inconvenienced, and answers by punching Sano back, and defeating him instantly.
In Princess Mononoke, a giant boar-demon attacks an Emishi village and the protagonist, Ashitaka, is forced to fight and kill him. In the struggle, Ashitaka receives a curse on his right arm, which grants him superhuman strength but will eventually kill him. Indeed, the main point of the movie is that bad things happens when you kill a god. For example, Lady Eboshi, trying to create a new home for her people, decided to kill the boar god, but unfortunately, she did it by poisoning him, leading him to degenerate to the Boar-demon that attacked the Emishi village, as well as to the boar-demon brother to seek revenge. Later Eboshi decapitated the Deer-god (which is much closer to an actual god then the other animal spirits in the movie), and as a result, The deer god goes One-Winged Angel and nearly kills everyone present there, and Eboshi has her arm bitten off by the head of another animal god.
In the third movie the power of the Reality Warper Unown creates mons that completely curbstomp everyone the heroes throw at them.
Notably in the 13th film Dialga, Palkia, and Giratina, three Legendaries among Legendaries that control reality, have this happen to them, when Arceus God of the Pokemon world decides he's had enough of them.
In Zeta Gundam, Camille defeats Scirocco by crashing his waverider into Scirocco's cockpit and crushing his body. With his dying breath, Scirocco mentally attacks Camille and leaves him catatonic.
Scirocco: "You may take my life, but I will take your soul!"
Eventually, he got better. Well, a little bit. Can't ever pilot again, but all it ever brought him was pain either way, right?
Averted in the movies, where Sirocco tries to pull a soul attack, but it visibly fails, and Camille manages to transform the Wave Rider back into Zeta Gundam. There's a certain feeling of triumph there, and game adaptations now follow through all the way to the transformation.
Mobile Fighter G Gundam, the third encounter with the Devil Gundam ends this way. In order to stop it, Domon finds he has to kill his brother Kyoshi who was at this point revealed to be Good All Along, and kill his mentor Scartwz. And the Devil Gundam gets rebuilt and returns again later.
Heavy Metal L Gaim: What happened to L-Gaim Mk. II in its fight against the original Aug. Although the arm was ripped off.
In Slayers Amelia tried to punch out the Physical God Ruby Eye Shabranigdu but broke her arm instead. And there's the Dangerous Forbidden Technique Lina often relies on to defeat such demon lords with. Each use risks destroying the universe if executed poorly ( by attracting the attention of The Lord of Nightmares, leaving the fate of the entire universe to the erratic whims of its now cognizant Demiurge,) like when Lina was swallowed up mind, body and soul to fuel it, only returning through a mixture of sheer luck and (in the anime) The Power of Love.
Dragon Ball Z does this roughly every time it turns around. One moment which comes to mind is when Goku uses his Kamehameha at Kaioken x4 in a Beam-O-War against Vegeta, with the fate of the planet hanging in the balance, and ultimately sends Vegeta flying into the stratosphere. Then Yajirobe gives Goku a light congratulatory slap on the back, and Goku screams in pain due to the Heroic RROD brought about by the Kaioken. Vegeta falls to earth, hurt but not nearly as badly as Goku is, and just transforms (Vegeta ironically wasn't aware this trope was in play and didn't know he nearly had Goku on the ropes)… The whole fight with Vegeta is this. He's beaten and forced to retreat from Earth, but Goku is on death's doorstep, and Gohan is left badly injured. And Vegeta recovers, though this is overshadowed by his recovery coinciding with an introduction of an even bigger threat, Freeza. Him surviving actually benefited the protagonists in the next arc
Tien often pulls this trope, over-exerting himself to near death (and in the fight with Nappa, complete death).
Tien has another case of this when overuses a Dangerous Forbidden Technique to try and slow down Cell to alone #18 to get away. The most he's able to do is slow him down, and his exerting himself left him too weak to even run away, and only survived because Goku saved him. And his actions proved futile in the long run anyways.
The backstory for Piccolo Daimou in Dragon Ball. Muten Roshi's master managed to come up with a technique to seal away Piccolo, but dies uses it, and Piccolo is later released anyways. Both attempts to reuse the technique fail, with Roshi screwing it up and dying, and Tien failing because Piccolo had a Mook take the hit for him.
Prior to the series, Queen Serenity's battle with the series first Big BadQueen Metallia, where the most she can do is seal Metallia away, and dies doing so, and while not all the details are given, Metallia apparently managed to kill the rest of the Senshi as well. Metallia's marks another case of this, with everyone but Usagi dying before she's finally killed in the manga, though Usagi undoes the damage of her rampage. The anime also ends with this way, with the Senshi dying fighting the DD Girls, Mamoru dying saving Usagi from Beryl, and Usagi as she dies from using the Silver Crystal to destroy Metallia, but she manages to revive herself and everyone else with it.
The third story arc, both versions when Sailor Saturn stops Pharaoh 90 from bring about The End of the World as We Know It, using her powers causes her to die and she only makes it back because Usagi saves her.
The manga ends this way. Eternal Sailor Moon does a Heroic Sacrifice to prevent the Anthropomorphic Personification of Chaos from rising. After she gets better, we're told that Chaos was not completely destroyed. Sailor Cosmos confirms that Chaos will be reborn as a Sailor Senshi itself, and that it will instigate a huge cosmic war that will tear the galaxy apart and that the damage and sacrifice necessary to destroy it will be just as bad as losing the war. While Cosmos traveled to the past to prevent its rebirth, she realized that Chaos' rise was inevitable and that there WAS no Third Option. Oddly the characters don't seem to perturbed by the bleak future that awaits them, preferring to enjoy their happy present lives taking comfort that life will always go on even if the galaxy is destroyed by war. To be fair, given that Cosmos's plan to stop Chaos would kill the galaxy, it's understandable that they were all right with their win.
Asuka feels the full weight of this trope after defeating the SEELE invaders and the Eva Series in End of Evangelion. The last shot of her half-devoured mecha juxtaposes it with the regenerated Eva Series joining Shinji's Instant Runes, heralding The End of the World as We Know It. Technically, Shinji Broke His Mind Punching Out 15 Cthulhi.
In Bokurano, the dimensional robots are so powerful that conventional militaries stand no chance. You do have Zearth, your own dimension robot which proved to be more powerful than some of them but it's run on your lifeforce and will drain you dead. Don't want to punch them? Your universe will perish. You can't lose a single fight, either. And if you try to reverse-engineer the robots, the guys in charge will just eat everyone on your planet.
This ends up happening to Jaden during his final duel with Yubel in Yu-Gi-Oh! GX; thanks to the nature of Yubel's monster effect, each time Jaden destroys (or forces Yubel to destroy) her copy, it merely evolves into a stronger version of itself. Eventually, Yubel becomes so powerful from Jaden's attempts to stop her, that the only way he could take her out is to intercept a Fusion Dance attempt of hers that would've resulted in The End Ofthe World As We Know It and use it to scrub the duel prematurely by fusing his soul with Yubel's, having the monster in his head for all eternity. It's not that bad; since Yubel was purged of the Light of Destruction when she and Judai got fused, and had all her Yandere urges satisfied, she calms down significantly and becomes friendly, if not a Deadpan Snarker.
During the Skypeia arc, the Badass Normal Skypeian, Wiper, goes one-on-one with GodEneru. After a tense fight, Wiper manages to kill Eneru by using the Reject Dial, at the cost of severe damage to his own body. Unfortunately for Wiper, Eneru's electric Devil Fruit immediately acts like a Magical Defibrillator, restarting the tyrant's heart. Sorry Wiper, looks like killing him once just isn't enough.
Later on, Luffy faces Big BadMagellan, who's coated in an armor of deadly poison. Luffy manages to get some hits in, but ultimately he isn't strong enough to keep Magellan down and succumbs to the poison.
The beginning of the HGSS arc of Pokémon Special starts off with Gold facing off against Arceus. Needless to say, his team is getting their asses kicked, though Gold says that they just have to hold out 'till Silver arrives. How that's going to make a difference is yet to be seen.
In Hunter × Hunter, Netero nearly kills the Chimera Ant King Meryem — possibly the most powerful lifeform on the planet at that time — by stopping his own heart to trigger the incredibly powerful bomb implanted in his own body. This desperate move only fails because two of Meryem's strongest minions sacrifice most of their power and body mass to restore him. Later, Gon utterly destroys Neferpitou, the second strongest Chimera Ant alive by forcefully aging himself to vastly increase his power. Said powerboost comes at the cost of a shortened lifespan and the possibility that Gon will never be able to use nen again. In a more literal example, Gon's right arm is torn off by zombie!Pitou when Gon lets his guard down thinking the battle was over after he crushed Pitou's head. Gon pins the monster down with his own ripped off arm and finishes it off with a final "rock" attack that apparently leaves Gon on the brink of death. However this is subverted when it's revealed the deadliest part about the bomb implanted in Netero is the poison that will kill everything that comes in contact with the bomb or people poisoned by it. That kills Meryem for good. Chapter 345 reveals that even after a Reality Warper saved his life, Gon still hasn't fully recovered. He cannot see or use Nen anymore.
Forms the backstory of Transformers Cybertron: the destruction of Unicron in the previous series had the side effect of creating an unholy abomination of a black hole that unless stopped using the series' Plot Coupons will annihilate the entire universe, possibly even the multiverse.
Medaka Box: This happens in a few instances, often to Zenkichi. Zenkichi kicks Oudo off of a building!only to find that it has no effect. Later he does a Heroic Sacrifice to try and kill Kumagawa. It works, but Kumagawa's reality warper abilities just revive him anyway.
Happens in Fairy Tail during the fight against Master Hades. Laxus realizes he can't defeat Hades, so he gives his magic power to Natsu. With Laxus' magic power added to his own, he singlehandedly defeats Hades. He then falls down, completely out of power and too sore to move at all, and watches helplessly as Hades gets back up and activates his One-Winged Angel move.
A number of characters in the Pretty Cure franchise are hit with this:
HeartCatch Pretty Cure! does this twice in the backstory. It's revealed that Kaoruko lost her powers as Cure Flower when she used so much energy from the Heartcatch Mirage to stop Dune, it shattered her Heart Perfume device. And Yuri is taken out of the fight for 3/4ths of the series when she uses her Pretty Cure Seed to block the Dark Precure's attack, the strain shattering it into two halves.
Pretty Cure All Stars DX 3 has all the girls lose their transformation devices to Black Hole, force them to use the MacGuffin to repower them and defeat Black Hole, then lose their powers and companions. For all of a few minutes on-screen.
Jonathan Joestar's apparent victory over Dio Brando in JoJo's Bizarre Adventure turned out to be anything but. Even as a disembodied head Dio mortally wounds Jonathan with a new attack. Jonathan only has enough strength left to ensure his wife Erina's safety and dies trying to take Dio down with him. After several decades, Dio returns from the bottom of the sea in Part III after attaching himself to Jonathan's body and boasting a new power that makes his vampiric abilities seem like parlor tricks in comparison. It's up to Jonathan's great-great grandson Jotaro to put Dio down for good. Part VI reveals that even this didn't stop Dio's legacy.
Naruto has the titular character's fight with Kabuto. Naruto, being heavily outclassed takes a pounding for most of the fight, with him only managing to land one hit on Kabuto, though it came in the form of the Rasengan. The attack did a lot of damage, but Kabuto almost killed Naruto by severing some of his heart strings, which would have killed him if Tsunade hadn't saved him, and Kabuto managed to get back on his feet to help Orochimaru. The most Naruto managed to accomplish was getting Tsunade to snap out of her Heroic BSOD, and win a bet she made with him stating that he couldn't master the Rasengan.
Villainous example in Naruto's fight with Pain. Seeing Hinata hurt prompts Naruto to lose more control and draw on more the Kyuubi's power than he ever has before, also losing control of himself to it. Pain attempts a stronger version of Shinra Tensei to stop him, but the possessed Naruto just breaks free while drawing even more power, and the Kyuubi nearly convinces him to break the seal and let him free. The trope is only narrowly averted by vision of the Fourth Hokage that he set up in case of such an event, which allowed Naruto to regain control.
Soul Eater has this as the backstory with Lord Shinigami's battle with Asura. Lord Shinigami defeated Asura, skinned him alive and used his skin to make a bag to seal him in, and then anchored his soul into a firm location to suppress Asura's influence and keep him sealed. As a consequence, this forced him into a heroic example of Orcus on His Throne since he could leave to deal with any other menaces that threatened the world, which hit especially bad in the present when Asura is released by Medusa and escapes outside of where Lord Shinigami can move. The Final Battle against Asura plays this trope twice. First when Crona tries to devour his soul. She seemingly succeeds, but then later he just breaks and berates her for her Genre Blindness. The protagonists try fighting Asura, but no shakes off everything they throw at him and in the end, after a reveal that Asura is in fact an embodiment of fear and can never die as long as fear exists (hence why Lord Shinigami didn't kill him), the most that can be done is reducing him back to a Sealed Evil in a Can, at the cost of Crona's life, whom Maka spent most of the series trying to save.
Thor managed to slay the Midgard Serpent - a giant dragon among giant dragons - with a massive hammer blow to the head. He was already in constant pain and obliged to wear a full-body armor suit for support due to a curse by the goddess of death, but the death blow reduced him to a pulped (yet still living) mass of flesh contained within said armor. Given he was prophesied to die after killing the Midgard Serpent, as per Norse Mythology; this is actually a plus.
A more graphic example was when he hit an invulnerable Viking named Herald Jaekelson so hard it nearly tore his hands off.
There are many times in the comics where Thor managed to break his hammer, Mjolnir, while fighting some of his most powerful enemies, usually by utilizing the Odinforce. One example is when he tried to fight Exitar, the largest Celestial, in one of his older comics and shatters his Mjolnir into pieces trying to break into its skull.
The only way for Dr. Strange to beat Shuma-Gorath on his home turf was to tap into the demon's power source. Using Shuma's power started to make him become another Shuma-Gorath though and "killing" Shuma only sped up the process, so Strange had to commit suicide. Luckily someone else was able to save the Doctor, which was good a while later when we learn Shuma wasn't permanently dead.
One Exiles arc features Galactus attacking earth, and for once he's actually at full strength rather than nearly dying from starvation. Eventually team powerhouse Thunderbird manages to break Galactus' skin and insert a device specifically made by that earth's Reed Richards to hurt the creature. Thunderbird is left brain dead from the shockwave though he does manage to get Galactus to flee.
At the climax of Marvel Comics' Generation One Transformers series, Circuit-Breaker, a.k.a. JosieBeller attacked Unicron with all her power, paralyzing him long enough for Optimus Prime to destroy him with the Creation Matrix. Sadly, however, Beller was left catatonic as a result.
Played straight litterally in Les Légendaires, where protagonist Jadina attempts to punch the God of Evil Anathos. Anathos stops her attack with one finger, and causes her arm to break in the process. Even worst, he mentioned she is lucky he needed her alive at that point, because otherwise he would have let her kill herself punching him. Then immediately subverted when Jadina Out-Gambitshim. And before this, Danael already suffered a case of The Virus against Anathos when coming up with a scheme to prevent him from reincarnating into Shimy, only to serve as the host instead of her.
In Final CrisisBatman shot Darkseid with a Radion bullet, mortally wounding him. The dying God of Evil inflicted the Omega Sanction on Batman trapping him in a cycle of death and rebirth into horrible lives and accelerated the universe's decay which his rebirth started out of spite.
In My Little Pony Micro Series Issue #2 the Sonic Double Rainboom certainly defeats the gremlins, but completely paralyzes Dash's wings for two months.
Occurs whenever Batman and Superman fight, if Superman doesn't outright win. An almost literal example in Batman Hush, when trying to survive against a Brainwashed and Crazy Superman, even with his krypnoite ring, Batman could land a few punches on Superman before not being able to punch him anymore because impacts broke every bone in his hand.
The Spiderman storyline "Nothing Can Stop the Juggernaut" has Spiderman's this in Spiderman's second fight with The Juggernaut. Struggling to find a way to hurt him, Spiderman tries ramming a tanker truck into him, and gets horrified that he might have killed him, but then finds it just made him angry. Ultimately, Spiderman manages to win the fight by tricking Juggernaut into a load of cement, but by end, he crawls out. Keeping the latter part of the trope from being played straight, Juggernaut doesn't go after Spiderman in the future.
Damnatus. All the heroes give their lives to try and stop G'guor, an Eldar spirit accompanying them pulls a Thanatos Gambit, and inquisitor Lessus invokes exterminatus on the planet, but the outro voiceover implies that G'guor will still be back someday.
The 1998 film Fallen is about a demon that can leap from one body to another instantaneously. It ends with the lead character leading it into the middle of the woods, then poisoning himself before shooting the demon's current host. Cut to a nearby cat, and the narration picks up again: "Oh! You forgot something, didn't you? Back at the start, I said I was going to tell you about the time I almost died. [chuckles] Be seeing you."
Alright! Rocky Balboa hass KO'ed the powerful Soviet superman Ivan Drago. He has avenged his friend Apollo Creed and won over the hostile Russian audience in the process. Rocky IV ends on a happy note... but leads into Rocky V, where we learn that Balboa has gone bankrupt. He tries to take another title fight to earn money, but the match with Drago left him with crippling brain damage which forces him to retire from the ring.
In the remake of The Haunting (1999), Elinor becomes a Christ-like figure, confronts the villainous ghost, Hugh Crane who has transformed into a twenty-foot, roaring, Witch-King of Angmar lookalike and defeats him with The Power of Love, banishing him through the Gates of Hell which are conveniently placed in his hallway. Don't ask. The spirits imprisoned within the house are released and Elinor conveniently dies. It's like something out a Saturday morning cartoon.
In How to Train Your Dragon, Hiccup loses half his left leg in the process of defeating the humungous dragon at the end.
At the end of Silent Hill, Rose finally rescues her daughter and defeats the Order by way of letting Dark Alessa have her Roaring Rampage of Revenge. However, when they leave Silent Hill, they're still stuck in the Fog World, and the movie ends with both them and her husband in their house at the same time, in two worlds, unable to communicate except for a single static-laden voice mail. In the sequel, it turns out that in the interim she somehow finds a way to get her daughter back to the real world, but not herself. Too bad for her, the Order was able to do the same thing with Vincent, thus setting up the events where Dark Alessa and the powers of the Order are defeated for good, Pyramid Head pulls a quasi Heel-Face Turn, and Heather, her dad and Vincent all get to go home, just as the permanent ash fall is coming to an end. They pass a prison bus heading into the town's general area, just as it starts to rain and the creepy music kicks up again, meaning that all they did was change who the instigators and victims were going to be.
The 2011 adaptation of The Whisperer in Darkness expands on the ending by having Wilmarth discover the Mi-Go performing a ritual that will open a portal and allow for a mass invasion. He succeeds in preventing said invasion, though most likely only temporarily. He is also unable to escape from the Mi-Go, with the final scene revealing his brain has been removed and placed into a jar for transport.
At the end of Predator 2, Harrigan kills the Predator, only to immediately face several more Predators that materialize in front of him. However, the trope is averted in that the others don't want revenge; on the contrary, they give Harrigan a gift and send him on his way.
In The Thing the characters are able to make a stand against the monster, but by the time they're done all but two are dead, and the survivors are likely to freeze to death. It's also not entirely clear if they actually succeeded in destroying the Thing or if they've only temporarily contained it, and there is a faint possibility one of the two survivors could be a Thing. To make things even darker there's an Alternate Ending where a dog is seen running away from the ruins of the camp, implying that the thing escaped, and Macready's efforts were for nothing.
In the Mouth of Madness: Poor John Trent tries again and again to punch out Cthulhu, but he just doesn't stand a chance. He constantly tries to find ways to outwit mad writer Sutter Kane, but the latter constantly remains one step ahead. Trent tries to burn the manuscript for an insanity-inducing novel? Too bad, another one shows up in the mail. He tries to warn the publisher to keep the novel from coming out? He already delivered the manuscript, the book's been selling like hotcakes, and there's a movie about to come out.
Occurs in nearly every successful attempt to stop Godzilla:
Godzilla's first fight with Mothra left the adult Mothra dead before the larva sealed itself off in a cocoon, and even that wasn't enough to stop him forever. The only thing keeping this trope from being played entirely straight is that Godzilla ends pulling a Heel-Face Turn in the later movies.
Godzilla vs Biollante is a case of this being played for Godzilla himself. He manages to kill Biollante, but the anti-nuclear bacteria he's infected with starts acting up so much he has to return to the sea and can't leave.
In Godzilla vs King Ghidorah, the cyborg pilot of Mecha-King Ghidorah isn't able to kill Godzilla and while she survives, Mecha-King Ghidorah is wrecked by Godzilla when it drags him out to sea, meaning all the fight did was temporarily slow him down before he returned for another attack.
The remake of Godzilla vs Mothra has both Mortha and her Evil Counterpart Battra teaming up against Godzilla. They manage to defeat him, but all they really do is drag him out to sea again where Godzilla kills Battra, meaning in the future Mothra would have to face him alone. She's not strong enough to stop him by herself, though Mothra didn't appear in the later films in this series as it is.
In Godzilla vs Space Godzilla, the humans built Humongous Mecha MOUGERA to stop Kaiju attacks. It fails completely its first fight with Space Godzilla. The second fight, it manages to destroy the crystals on his shoulders, which prompts him to wreck the thing so badly the crew is forced to abandon it. Godzilla later finishes the job and completely destroys the robot after killing Space Godzilla.
In Godzilla vs Megaguirus, humans try to kill Godzilla using a Kill Sat that fires an Unrealistic Black Hole. Not only does this manage to do little more than inconvenience him, it causes a horde of giant insects to appear, including the titular Megagerius. The only thing that stopped them was Godzilla himself. The humans try the weapon again and it apparently kills him, up until the last scene of the movie, where we hear him roar again indicating he survived.
Godzilla All Monsters Attack, has all three of the Guardian monsters that were meant to stop die trying. Some quick acting by humans manages to seemingly kill him, but his heart survives and starts to regenerate his body, meaning he'll return, and this time there won't be any Kaiju to stand in his way.
Godzilla Final War, a rare case of this not involving Godzilla. Instead it's when Mothra fights Gigan at the climax of the movie. Mothra manages to keep Gigan out of Godzilla's fight with Monster X, but he injures her fatally before she can kill him.
In The Silmarillion, when Fingolfin sees all his army defeated, he rides to the very gates of Angband to defy Morgoth himself, inflicting several wounds to him. It doesn't end well. However, he did inflict wounds on Morgoth that would never heal. There's a reason why this is one of the greatest Crowning Moments of Awesome ever.
The final battle of the First Age could qualify too, sure the hosts of the Valar have destroyed Morgoth's forces and he's captured and beaten, but the entire continent that everyone not living in Valinor has called home since the dawn of time ends up so damaged it breaks apart and gets swallowed by the sea. Though Morgoth is sealed beyond the Void, it turns out one day he will escape leading to the Dagor Dagorath, the final battle the will destroy everything.
Melkor essentially writes suffering and imperfection into fate before the world's creation, and after he becomes Morgoth pours his essence into Middle-Earth itself, so that even after his spirit gets banished his presence remains; he is the evil that exists in the world.
Two examples occur in The Lord of the Rings. First, Gandalf's famous Heroic Sacrifice, when he killed the Balrog but died from the ordeal. Second, Éowyn's shield arm actually was broken by the Witch-King, but that wasn't the worst wound she suffered; just touching the Witch-King is enough to seriously harm you, so when she and Merry stabbed him, their respective weapon arms were hurt and they needed special medicine to recover. Éowyn wound up so deeply comatose she was at first mistaken for dead.
In The Dreams in the Witch House, a fellow manages to stop a servant of said Eldritch Abomination, but is unable to save the child from sacrifice. Though he manages to stay sane throughout the ordeal, he is later killed by an Eldritch Abomination drilling itself out of his body as punishment, and his friend, seeing this, ends up in a mental institution.
Even the originalThe Call of Cthulhu had a textbook example of this. When the titular Thing attacks, a sailor rams him with a yacht, forcing him to retreat back to R'lyeh. The problem is, Cthulhu is still very much alive, having reformed soon after getting punched out. As for the sailor, not only does the entire ordeal push him off the deep end, but it's hinted that Cthulhu's cultists kill him soon afterward. Ironically, Cthulhu himself isn't even all that high on the power-scale of Lovecraftian abominations. Yes, he's bigger than a Deep One or Mi-Go, but he's really just a mouthpiece for the real cosmic-caliber deities like Azathoth and Yog-Sothoth.
Any kind of victory over Lovecraft's Eldritch Abominations, is, at best, delaying the inevitable. Which is the point of the expansion to the Call of Cthulhu role-playing game, Delta Green. A task force, that doesn't officially exist, whose duty is to 'delay that inevitable' for another few years, and continually.
In The Heroes of Olympus, the gods of Olympus are in no shape to fight a war against the giants precisely because they're still broke from fighting the Titans and Typhon.
A literal case in the first book of War of the Dreaming: Peter Waylock attempts to use Thor's hammer against an enemy sorcerer, and ends up breaking both his arms — not good, considering he also can't walk.
In The Wheel of Time, the Dragon (no, not that one) took independent action and led a strike force of male channelers in storming Mordor and sealing the hole in the Dark One's prison. (He disregarded the original plan, to include females and use certain absurdly-powerful power-enhancing artifacts, after the forces of evil overran the locations of the access keys to said artifacts and political strife among the channelers resulted in all female Aes Sedai refusing to participate.) Good news: mission accomplished. Bad news: the Dark One subsequently tainted the male half of the One Power, thereafter driving anyone who used it insane and thus causing the Breaking of the World—the face of the world reshaped, billions killed, and the entire utopian society crushed into mythology. Though the society was kind of in the crapper from a decades long war against the forces of darkness anyway, though at least not entirely broken up.
In Sabriel, Sabriel's father uses the bell Astarael, which sends anyone who hears it deep into Death, to try to permanently kill the book's undead villain. It doesn't work. It does, however, delay him enough for Sabriel to get away and find a better way of killing him. Which also doesn't work. So she seals him away instead.
In Abhorsen, the only way to seal the Big Bad would result in the death of the caster of said seal thanks to a backlash effect and the Big Bad trying to take her with him. Lirael goes through with it anyways, but survives when the Disreputable Dog bites off her hand, saving Lirael's life.
A frequent Downer Ending in Philip K. Dick short stories. In "Faith of our Fathers", the Eldritch Abomination in question turns out to be God, and the minor wound the hero received in the encounter ends up being fatal. However, it is seen as a vaguely optimistic outcome, as it's hinted rebellion is impossible, so his minor act of defiance (in punching Cthulu in the face) is a victory for the human spirit. After he is 'branded' as a result with a deadly sore, which slowly spreads over his body, he chooses to ignore it and spend his last night alive making love with his girlfriend as an act of humanity, denying Cthulhu a moral victory.
In a short story by David Brin (which was made into a comic book) a soldier broke the spear by which he ought to have been killed over his knee. The spear belonged to Odin, and his knee didn't really like the treatment.
In the Warhammer 40,000Blood Angels novel Deus Sanguinius, Rafen manages to slay the Eldritch Abomination Malfallax. However, Malfallax's death comes with a curse that triggers the Black Rage in all of the nearby Blood Angels, and while Rafen manages to free them of it, Malfallax's true form is still alive in the Warp, plotting vengeance on him.
The first arc of the Deathstalker series ends with the protagonist delaying the Recreated long enough for them to be restored to their true forms. However, the stress of doing so leaves him too exhausted to return to his point of origin or even fight effectively. Instead, a man who destroyed countless armies is murdered by a pack of half-mad drug addicts, far from friends and allies. They even took his boots.
Harry's origin story goes both ways. Voldemort as Cthulhu: Harry survives Voldemort's attack, but both his parents had to die in the process, Voldemort is left alive as a wandering spirit with a big grudge against Harry, and Harry is now a Horcrux, carrying a piece of Voldemort's soul around with him. Harry as Cthulhu: Voldemort kills both Harry's parents. But when he tries to kill Harry, who is protected by The Power of Love, his spell backfires, destroying his body and forcing him to wander as a spirit until someone can forge him a new one.
In Chamber of Secrets, this almost happens to Harry — he kills the Basilisk, but is poisoned by its venom, and he would have died if it hadn't been for the restorative properties of phoenix tears. This is probably a homage to the multitude of serpent-or-dragon examples of this trope listed under the Mythology heading.
In Deathly Hallows, Harry is forced to give his life to stop Voldemort (who, due to his extensive use of Horcruxes, is now a borderline Humanoid Abomination). The reason for this sacrifice is that during his failed attempt on Harry's life, Voldy accidentally transferred a bit of his soul into Harry's body, turning Harry into a Horcrux. This means that as long as Harry is alive, Voldemort can't die either, because a bit of his soul will be tethered to Harry's body.
The good news is that the reverse is also true—that due to a complex bit of magic that occurred during Voldy's resurrection, Harry's soul is bound to Voldemort's body, allowing Harry to return to life without the soul fragment in him. This means that after Neville destroys the final Horcrux, Harry can finally kill Voldemort.
In 1984, Winston and Julia break their souls failing to punch out Cthulhu.
In the Chronicles of Prydain book The Black Cauldron, the only way to destroy the eponymous Artifact of Doom is for someone to willingly throw himself/herself into the Cauldron, an act that would kill that person as well. Prince Ellidyr, who for most of the book was a Prince Charmless, saves the day by making the sacrifice.
The Goosebumps book How To Kill A Monster ends with the heroes captured by the monster, even after their attempts at killing it by making it fall through the stairs and poisoning it. Said monster is allergic to humans, and keels over dead after merely licking one. Unfortunately, the monster's friends are pissed off after this. Cue the terror, as the book ends with the heroes alone, far away from town, and in a marsh filled with these hungry, soon to awaken creatures. Hopefully the other monsters are allergic to humans too.
Moby-Dick is an early example of this. Ahab spends the entire story relentlessly pursuing the unusually large whale in search of revenge. This determination gradually reduces his sanity as he becomes more and more obsessed with his target. When he finally does catch up to the whale, it takes the lives of all but one of the crew, and it's not even clear if Ahab's efforts even hurt it.
In The Bartimaeus Trilogy book Ptolemy's Gate, Nathaniel uses Gladstone's Staff to destroy Nouda, but he did so by exploding the staff at point black range, ending in mutual kill.
In Jerusalem's Lot, Boone manages to destroy the book, De Vermis Mysteriis. But the evil is not destroyed (Boone notes, "The burning of the book thwarted...it, but there are other copies"), and to cut his family's ties to the evil, he dives into the ocean. Unfortunately, that doesn't work either, as a descendant of the Boone line takes up residence in the ancestral home, and events begin again.
In IT, Eddie Kaspbrak loses his arm battling the title monster, and dies. He does weaken the creature enough for the rest of the Losers' Club to kill it.
In the seventh season of Buffy the Vampire Slayer, the Scoobies take on The First Evil, who cannot take corporeal form and therefore can't be killed. They manage to defeat its army, but only after destroying the Hellmouth by blowing up Sunnydale and after the deaths of Spike, Anya, and several potentials. Even then, they never truly defeated it. How can you defeat pure evil?
In the season five finale, Sam Winchester deliberately breaks his arm punching out Lucifer when he, after inviting the Devil to possess him, somehow manages to throw the both of them back into the Devil's Cage. The upside: the Apocalypse is averted. The downside: Sam's soul is trapped, for the foreseeable future, in an abyss with an enraged and betrayed Satan. The personal kickback is nonexistent.
In the season seven finale, Dean and Castiel manage to kill Dick Roman, thus stopping the Leviathans' plans to Take Over the World. However, the backlash from Roman's death drags Dean and Cas into Purgatory along with his soul.
The basis of the Wraith conflict in Stargate Atlantis. The tech level of Earth and its allies is enough to hold them off, but there are so many of them each victory is just delaying the inevitable.
The first 8 seasons of consist of the Tau'ri and their allies trying to avoid (and sometimes causing) Type 6(ish). As the Tok'ra are fond of saying, lots of warring Goa'uld are preferable to one all-powerful Goa'uld.
In season 10, SG-1 manages to "kill" all of the Ori (they're energy beings so "kill" isn't quite the right word), but this doesn't stop their followers from continuing their war on the galaxy. It also means that when Adria ascends, she now has all the power that was once split among all the Ori. This makes her insanely powerful.
This trope very nearly comes to pass in the Season 4 finale of Angel, when Angel narrowly succeeds in thwarting rogue Power Jasmine's attempt to brainwash the entire human race for its own good by breaking her powers of illusion. While this does weaken her somewhat, it mostly just convinces her that humanity should die instead. Thankfully, Angel's son Connor (who is Jasmine's mortal father) turns up and manages to punch her out for good. Hey, being Cthulhu's dad has its advantages.
And the trope then does come to pass, as with her out of the picture, the human race goes from its Jasmine-induced state of perfect understanding and empathy with all other human beings to normal. The crash brings out suicidal and homicidal tendencies in most of the population, including Connor himself. The good guys are forced into a Deal with the Devil for a Reset Button and the Devil in question claims to be dealing with them out of respect for their demonstrated aptitude for inflicting pain and suffering on levels its own minions had failed to match. The messenger of said Devil starts out by congratulating the heroes for "thwarting world peace". Nice Job Breaking It, Hero.
The series finale features Angel and his gang causing as much damage as they can to Wolfram and Hart, having determined there is no way to take down the Senior Partners themselves. They successfully destroy their agents on the mortal plane and disrupt operations enough to set back the apocalypse significantly. However, the time they purchased for Earth costs them heavily and the Big Bad send an army to make their displeasure known.
And the comics show that this results in L.A. being cut off from the rest of the world and plunged into Hell. Nice Job Breaking It, Hero.
In "The Tale of the Curious Camera" the protagonists destroy the camera by making it take a picture of a mirror, but the demon possesses a video camera instead. Then they smoke it out of that, only for it to invade the computer.
In "Pinball Wizard", Ross wins the life-size pinball game, but is doomed to replay it forever.
In "Super Specs", the attempt to close the portal to the parallel universe results in that universe taking over "our" space and trapping the heroes in a Pocket Dimension.
In Doctor Who "Bad Wolf/The Parting of the Ways" when Rose Tyler uses the power of the Time Vortex to destroy the Daleks she is nearly killed by the vortex. The Doctor saves her by absorbing it, but this causes him to regenerate.
In the Big Finish Doctor Who story Neverland the Eighth Doctor saves Gallifrey from being infected by Anti-Time by materialising the TARDIS around the satellite containing the Anti-Time. However in the process he is infected with Anti-Time and becomes the monstrous Zagreus.
Jyu Ken Sentai Gekiranger: the show's penultimate episode has Rio attempt a suicide attack on Long's One-Winged Angel, which so appeared indestructible and has easily beaten the Gekirangers with they tried to stop him. Rio enters long's body and release all of his ki causing both of them to explode apparently killing them both. But, as Long reminded us already, he can't die, right as appears again a few seconds later and mocks how Rio just gave his life for nothing.
In Greek Mythology, Sisyphus managed to cheat death by chaining up Thanatos. However, doing so messed up the whole cycle of life and death. So eventually the impulsive Ares frees Thanatos, and Sisyphus was dragged to the underworld. His punishment? Sisyphus must roll a boulder up a steep hill... But it will always roll back down again whenever he's almost at the top, forcing him to perform this pointless task forever. In some versions he doesn't have to, he was just told he'll be let out if he actually manages it and he refuses to give up.
Ragnarok, the end of the world in Norse Mythology, is full of this. The gods kill the giants and monsters, but almost all of them get killed in the process. Odin gets killed by the giant wolf Fenrir, but is avenged by his son Vidar. Thor kills Jormungandr, the Midgard Serpent, but dies of the monster's poison. Loki gets killed by Heimdall, but not before bringing Heimdall down with him. And Tyr and Garm kill each other. Double subverted in the Sigurd legend, where he is warned beforehand that the blood of the dragon Fafnir is very poisonous, and builds a special pit trap to channel the monster's blood away from him. But then he finds out too late that a piece of the dragon's treasure - a ring - is cursed, and it becomes the catalyst in a long and bloody plot arc that eventually got adapted into a Wagner opera and likely served as the inspiration behind another cursed ring.
In some versions of the Mordiford Wyvern legend, the dragonslayer Carston is poisoned to death by the monster's blood.
In the legend of the Lambton Worm, Sir John Lambton is told by a wise woman that after killing the dragon, he must kill the next living thing he sees or else his family will be cursed for the next nine generations. He tells his servants to send a dog into the swamp after he signals his victory, but his father gets overexcited and runs ahead of the dog to congratulate his son. Sir John can't bring himself to kill his father, so he gets the curse.
Kate Bishop successfully managed to defeat the Maelstrom on Adventurers' Island, but the whole ordeal combined with several other discoveries about her past ultimately pushes her over the deep end.
The team did eventually expel the Maelstrom from the planet, but it is still very much alive, and there is no guarantee that it won't someday try to come back. Additionally, at least half the cast died in the process of achieving that temporary victory, as well as the fact that Kate, Sam Race, Sarah Bishop, and untold numbers of other survivors were severely traumatized by the experience.
The entire premise of the Arkham Horror Board Game. You can stop the Big Bad, but they'll always be back some other time.
In Call of Cthulhu, it's possible (if your investigators are insanely brilliant and cunning) to hit Cthulhu with a nuclear weapon. The game has rules for what happens when you do this. What are the rules? Cthulhu regenerates about 15 minutes later... but now he's radioactive.
Does that mean that if we keep hitting him(it?) in an organized manner every 10 minutes, the problem will be solved? Can side-effects of regeneration be harnessed to produce power? Cthulhu-powered Orion spaceship, anyone?
There is nothing that humanity can do which will kill Cthulhu for more than 1d10+10 minutes. When the stars are right, everything is over. Until then, you might be able to put him back to sleep until next time, at the cost of your sanity and probably your life. And as an added bonus, in the event of Cthulhu's death (which there is no known way to cause) he will be immediately reborn from one of the other eldrich abominations.
In Exalted, the Exalted killed the Primordials. Their Death Curse has led to two apocalypses so far and counting.
Also, She Who Lives In Her Name's last act before being sealed away was to Ret Gone vast swathes of Creation into nothingness. According to accounts by The Fair Folk, who witnessed the whole sequence of events from outside creation, even the splendor of the First Age was just a tiny, burned-out remnant of what Creation used to be.
To be more specific, the Ret Gone didn't just destroy physical area, it supposedly annihilated nine-tenths of Creation on a conceptual level. Whole principles of being ceased to exist, leaving only what players and characters understand as conventional reality. It's a reality with magitech, super-sorcery and god-given Elder God-smacking heroes. But the implication is that the time before the Three Spheres Cataclysm is more or less impossible to wholly comprehend.
Kult plays with this. Humans are actually super beings who are unaware of their power. Various supernatural forces try to prevent humans from being awakened, yet their efforts seem to be futile.
This is why you can't kill a Titan in Scion - Fate, being an utter asshole in the Scion universe, will go berserk if something that big is taken out of reality. When Ymir died, the Ice Age ended, causing worldwide catastrophe. The best the Gods can do is make the Titans into Sealed Evil in a Can.
The whole business of fighting Chaos in Warhammer 40,000. Any really powerful daemon simply cannot be destroyed by physical means, as they live in the Immaterium, and there's exactly one psyker powerful enough to fight them on their turf... and he's on the life support for the last ten millennia. All that He Who Fights Monsters could do is to banish the daemons back to the Warp, for them to return again later. Even though such banishments aren't exactly the bed of roses even for the Daemon Princes, and many lesser daemons could be vanquished entirely with proper procedure, this fight is essentially a defensive one, with no chance of a true victory. And the Enemy is dangerous indeed.
For example, take Lucius the Eternal, Champion of Slaanesh, one of the aforementioned Great Champions. If he is killed in battle and the foe takes even the slightest satisfaction from or pleasure in his death, he possesses his killer and eventually takes him over entirely, with the former victor now nothing more than another screaming face on Lucius's armor...
What if the Necrons or other mechanical beings manage to kill Lucius?
The whole idea behind the Tarrasque ("The", not "a"; also note the capital letter) in Dungeons & Dragons. It's a mouth with a giant body attached to it. It wakes up every couple of years for a few days, then just chows down on everything in sight, demolishing whole kingdoms before going back to napping. On the off chance you manage to fight it, you're in for a big one. It can remain conscious and fighting all the way down to -30 HP (and it has a lot of health to start with) and regenerates health automatically no matter what happens. The only way to permanently kill it is with a Wish spell, and that has a 50% chance of allowing it to come back after a while. Don't have a Wish spell? Your best bets are to either bury it alive (it won't die, but it will remain unconscious at -30 until somebody decides to be a dick and unbury it) or put it at the bottom of the ocean (it will manage to surface eventually, but it will take a long time; it will get enough health back to swim about five feet up, get knocked unconscious from drowning, get a bit more health back and keep doing this... until it surfaces).
The fourth edition decided to cut directly to the chase: Defeating the Tarrasque merely makes its physical form sink back into the earth, from which it is inevitably revived. All you've done is cut short its current rampage. The Tarrasque in that edition is a curse laid upon the earth by a being older than the gods, and cannot be undone by mortal hands. In Pathfinder it is non-killable: It will revive automatically no matter what you throw at it.
Magic: The Gathering: if one of the big colourless Eldrazi - even the weakest of them - attacks, you will automatically have to sacrifice a permanent even if you manage to kill it. Emrakul, the Aeons Torn, will cost you six permanents. Meaning that even if you're able to kill the creature, you will have lost quite a bit of board presence.
Call of Duty 4's ending ends up with everyone dying, whilst trying to escape from saving everyone in America from a nuclear death, killed by the man that set off the nuclear devices in the first place
Apparently, Modern Warfare 2 also suffers this with almost everyone dead because of General Shepherd's betrayal in an attempt to write his name in history, thus revealing him to be the Big Bad and having all those who know about it and pose a threat to him killed off. Luckily, He gets killed but now the protagonists are branded as terrorists and are hunted across the world.
Doesn't really matter that he's dead. He got what he wanted (a call to action in order to restrengthen America's fighting force), he's just too dead to take command of the subsequent fallout. That duty will fall to someone else. But he got the blank check and the war he had envisioned, which is all that really had to succeed in his plan (him being alive would simply be a perk, and if anything, two rogue soldiers who were supposedly working under him now being responsible for his death could only amp up the call to action). The very essence of the trope exemplified.
X-COM follows this trope with Terror from the Deep. X-COM forces manage to destroy the Eldritch Abomination that the aliens were attempting to revive that definitely would have killed humanity (being effectively invincible once awoken). Unfortunately, the alien city T'leth (in which the abomination was sleeping) managed to rise above the waves before the final victory, and explodes rather spectacularly. This first of all kills all the aquanauts who secured the final victory, and second, severely poisons huge swaths of the ocean and setting off cataclysmic cascading environmental disasters, such that by the time of the final game in the series, X-COM Apolcalypse, the earth has almost completely been reduced to a wasteland.
And by the end of Apocalypse, humanity's last bastion of hope, Mega-Primus, has been devastated by the extended interdimensional war.
Except that, by that time, humans already have a number colonies on other worlds, including Mars, as per Interceptor. Furthermore, the original plan was to build a number of Mega Cities to hold all of Earth's population, but the enormous costs only allowed them to build the prototype - Mega-Primus. It's possible that they may build others eventually.
Resistance follows this trope, as in the sequel, you find out despite your effort to take down the spire in London, they managed to get to the United States, and most of the United States has fallen against the Chimera.
Bet you the final one will make humanity officially extinct.
Resistance 3 continues the trend. Despite Hale's work in Resistance 2, humanity has officially lost the war against the Chimera. You play as Joseph Capelli, who works with La Résistance to give punching out Cthulhu one last go. Let's hope he finds more success than Hale did.
The process of defeating Lavos in Chrono Trigger resulted in it absorbing the Mysterious Waif who had power over space and time. Now in Chrono Cross, the result is far worse, an entity that consumes time itself, who cannot die because there is always another timeline where it didn't die.
Most of the defeats of Dark Matter in the Kirby series seemed to be type 1 of this, with Dark Matter just coming back meaner and with an even more grand attack on the Kirby universe in the next game. So far, it looks like he finally is dead for good after Kirby 64. Humorously, Kirby doesn't really care; as long he carries his MacGuffin weapon all he does is smack the shit out of Dark Matter and return to eating and sleeping.
Everyone in Eternal Darkness, with the exception of the main character, it seems.
Not really, since each character's actions added up and destroyed all three evil abominations at the end, thanks to Mantorok's Taking You with Me scheme.
One case we have a character that believes in this trope that his actions against the Ancients will bring this about, but most hints of the plot is that he survived, likely since his actions didn't do anything to stop the Ancient that is the antagonist in storyline you're playing in, but serve the purpose of preventing the one you summon to kill Pious' Ancient from destroying the world itself, but he had no way of knowing that.
In Neverwinter Nights 2: Mask of the Betrayer, it is likely that the person who kills the spirit-eater will receive the curse next. Also, you can try to devour the soul of Myrkul, but Kaelyn will advise against it, warning that doing so might result in this.
In Gears of War, the game ends with the heroes dropping the Light Mass Bomb on the overwhelming Locust Horde. However, when Gears of War 2 begins they find themselves pushed back to their last defensive position with a new sickness called Rust Lung spreading among the human population.Gears of War 2 also ends with humanity sinking Jacinto, the last refuge they have against the Locust. Good idea! Problem: it might not have worked, so humanity is now defenseless if the Locust are still alive in any shape or form. According to Gears Of War 3, it didn't.
Persona 3's heroes defeat the avatar of Nyx, but unfortunately, Nyx just keeps on coming, responding to humanity's subconscious wish for death. The main character has to sacrifice himself to hold Nyx at bay permanently. Then in the Expansion Pack, the heroes end up just going ahead and beating up humanity's subconscious wish for death itself - but even then, it's stated that it's going to take a lot more work to solve the root problem.
Yes, but it's not usually taken to this extent. Nocturne, for example, ends on a fairly upbeat note if you get the Freedom ending (if we ignore the fact that you have simply given this incarnation of the universe some time until God decides to reboot it again). Persona 4 completely averts this, and strongly hints after beating Margaret that Persona 3's main character's death might be somehow reversible.
Actually, that's the extent it's always been taken to in Persona. In the first one, Defeating Pandora causes Maki's ideal world to disappear, along with ideal Maki. Which means the actual version of Maki that the characters got to know and care for disappeared into the ether. In Persona 2 Innocent Sin, they fight and defeat the literal incarnation of humanity's malice, only to have one of their allies die, which in turn fulfills a prophecy that causes the end of the world. The only way to fix it? Strike a deal with an entity of immense power to rewrite history... effectively undoing all the personal growth the characters have experienced and significantly weakening the side of good.Persona 2 Eternal Punishment, in a rematch against the big bad, one of the main characters has to be sacrificed because his mere presence gives tips the scales in the big bad's favor.
Nocturne implies that the protagonist of Shin Megami Tensei II was cursed with a Fate Worse than Death for killing YHVH in the climax of that game. It didn't even stick, as YHVH/God will keep coming back as long as anyone believes in him. The Demi-Fiend can put himself in a position to help take down God for good... By allying himself with Lucifer, discarding his humanity and then destroying all of Creation, leaving no humans left to resurrect God with their faith. Even then, the ending doesn't say if you succeed, merely that Lucifer is preparing for a second Rebellion — and you just invoked It's Personal against God.
In the first game, Dracula curses Simon Belmont just before he is killed, giving him wounds that would never heal. Subverted in the sequel when Simon gathers up Dracula's body parts and resurrects him to kill him again, releasing himself from the curse. Yes, that's right. He punched out Cthulhu, broke his arm doing so, then brought back Cthulhu and punched him out again with the broken arm.
In Castlevania: Chronicles of Sorrow, Julius also paid a hefty price for his victory against Dracula. While he does kill Dracula for good (reincarnation doesn't count), he loses his memories and becomes an amnesiac wanderer that gets trapped in Castlevania for decades.
In the ending of Killzone 2, Visari is dead, but at what cost? Most of ISA's military force is destroyed and its remnants are stranded on Helghan and Helghast has some of the ISA's nuclear arsenal ready to use on them, and the bulk of their forces were just in hiding.
However, ISA being invaded is the least of the characters concerns since Visari's death has effectively started a civil war...oops
In Supreme Commander: the means by which the war was ended by the unspecified victors comes back to bite everyone in the ass in Forged Alliance.
Final Fantasy V, the first fight the party has with Exdeath. Only Galuf is able to fight, and he isn't able to kill him, just drive him off, and dies from the injuries he gains in the fight.
In Final Fantasy VI, Celes manages to stab Kefka... it just happens to coincide with him becoming a God and destroying the world. It's a long, long time before the heroes are able to try a second time.
Final Fantasy VII Cloud's fight with Sephiroth in Neblihim is revealed to have been this late in the game when Cloud gets back his memories of it. Cloud runs Sephiroth through with the [[BFS Buster Sword, which fails to kill him and gets him impaled with the Masamune, but while stabbed he manages to grab hold of it and toss it and Sephiroth into a fissure that leads him to falling into The Lifestream before passing out his injuries. Shinra afterwords made an effort to cover up the whole incident, which lead to Cloud's friend Zack being killed and Cloud left on his own. And of course, Sephiroth wasn't gone for good, having avoided being absorbed into The Lifestream and continued his plans.
In Final Fantasy IX, your party manages to defeat the apparent master mind behind everything... which allows Kuja to take control of the Invincible. Then your party beats up Kuja... which causes him to compliment you because he was depending on your party driving him to the edge so that he can go Trance (which he learned how to do during the course of your party punching out a lesser Cthulhu) and mainline the souls stolen by the Invincible into himself to make him a planet destroying god.
And when they are able to find one it causes the main character (the saved summoner's Love Interest) to cease to exist, since he was from a dream world sustained by the same entity responsible for creating Sin. FFX-2makes this all better by bringing Tidus back in the best ending.
In Final Fantasy XIII-2, where you kill the Immortal Guardian Caius, and everything seems to be well, only to be kindly reminded that the heart of the goddess of time and death was beating inside his chest and by stabbing it you killed her, making time, life and death cease to exist. Which was Caius' goal all along. Nice Job Breaking It, Hero.
The game also sheds a new light to Final Fantasy XIII, when you find out that, in fact, your arm should've been broken when you killed Orphan, and the only reason it didn't was because the Goddess took pity and resurrected everyone, thus creating the time rift that caused all the events in the sequel to happen. Which means that if the benign Cthulu that you accidentally murdered in XIII-2 hadn't saved everyone in XIII, she wouldn't die and... break everybody's arm. So to speak..
Final Fantasy Dissidia has this in its sequel Dissidia 012 when the the prequel cycle, Cloud, at the time a warrior on Chaos' side, turned on Chaos out of fear of Tifa being hurt in the conflict. After a fight in game, Chaos simply laughs off Cloud's attempt and kills him, which led to Cloud being revived in the next cycle as a warrior on Cosmo's side, but his death in the battle meant he longer had the memories of the early cycles
The hero of the first Diablo game winds up with a case of The Virus, since the only way he could come up with to utterly stop the Lord of Evil was to shove a chunk of it into his face. The hero of Diablo II figures out a better way... and hits it with a hammer.
Mega Man X: Sigma breaks his arm (or more accurately, his brain) when he first beats the first Cthulhu Maverick Zero before the events of the first game. Defeating Zero causes his own infection with the Virus, which he then mutates by adding his own consciousness to it, turning him into the Big Bad and Cthulhu for most of the series to come.
In Halo lore, the Forerunners were forced to activate the Halo Array and commit mass suicide to stop the Flood from taking over the galaxy. The downside? It only sent the Flood to sleep, and now the galaxy is defenseless. And also, because every species that was picked to survive the firing eventually discovered the Halos, the Flood are released again, and nearly take over Earth once they're able to infect a Slipspace-capable ship. Though they are stopped by glassing part of Africa, they then begin a plan to have the humans and Covenant Separatists deactivate the Halos and then double cross them, hoping to kill them all.
They are then fittingly taken down by Cortana's own plan, having lured the Flood to the one place in the universe where the replacement Halo (which was destroyed in the first game) can be fired to kill the Gravemind without actually hitting the rest of the galaxy.
However, this trope comes back if Cortana's story in Halo Legends: Origins (in which she was a Rampant Unreliable Narrator) is true in certain respects. If the right parts are true, the Flood are still around, and our heroes can't use that plan again.
In the E3 video demo of Scribblenauts, God, riding a skateboard and holding a shotgun, fights Cthulhu. As per the trope, they both die at the end of the fight.
The question is: which one was supposed to be the Cthulhu, given the choices?
In the lore surrounding Warcraft, Aegwynn, the super-powerful Guardian of Tirisfal, comes up against the avatar of Dark Titan Sargeras and defeats him with surprisingly little effort. The downside? Sargeras' spirit escapes his dying body and enters Aegwynn's womb, possessing her unborn child who later becomes the first game's Big Bad.
Disgaea 2's worst ending is essentially this: After Rozalin/Overlord Zenon awakens again, she's not in the mood to listen to any reason and Adell is forced into fighting her. He accidentally kills her in progress, which doesn't inconvenience her spirit too much as she possesses Adell and the first thing she does is to make him eat/brutally kill his siblings.
An inevitability in Warning Forever, in which your tiny ship fights an enemy that comes back bigger each time after it dies. It evolves to cover whatever weakness you exploited last time, so no matter how skillfully you defeat some ultimate form it had developed, it will be back, and while you'll be exhausted from the last fight, it will only be strengthened by your efforts to destroy it last time.
World of Warcraft has the Lich King Raid as its epic moment, after your party broke their arms trying to punch them. Tirion goes in and helps do him in. Yes Arthas is dead, but there is still a need for another Lich King so Bolvar offers himself to the throne. So much for a victory feast with the Alliance and Horde as Azeroth celebrates the lich king's defeat
Arthas himself has an origin story involving versions 4 and 5 of this from trying to defeat the Scourge...
Kael'Thas' defeat at Tempest Keep was "only a setback," which you learn when you fight him again at Magister's Terrace.
The Old Gods are THE Eldritch abominations of warcraft, unfortunately, they're also burrowed into Azeroth's core, killing even one may result in the planet dying.
Actually, Word of God confirms that it's not possible for us players to permanently kill any of the Old Gods at all, the best we can do is force their influence out of Azeroth. Temporarily. At best.
There appears to be a way to permanently remove the effects of the Old Gods (and probably expel them permanently, or at least force them to start from scratch). However, it would result in the death of every living being on the planet by activating the Reorigination Device (a planet-wide Reset Button). There may be other problems with this, as the Titans chose to not use it between when they noticed the problem and their departure from Azeroth.
The Klaxxi, a faction from Mists Of Pandaria, claim that they have existed since before the coming of the Titans, and that they worshiped an Old God that was slain by the Titans (and the Sha is the faintest echos of this entities power still in the world). If true, then previous lore about the world being the domain the Elementals before the Titans came is wrong. But, both stories are from an Unreliable Narrator.
The Sha(the shadow of an Old God's corpse) are the result of killing Old Gods though as Y'Shaarj has shown they can be manually be ressurected as long as part of their body exists(the Heart of Y'Shaarj had to be destroyed for him to be Deader than Dead) and their past selves can reach through time as shown by the War of the Ancients trilogy so in order to stop them permanently they must be erased from history itself! Yogg-Saron confirms his death and the rising of Sha from his corpse.
Kingdom Hearts: Birth by Sleep: One of the main characters, Ventus, loses his heart as a result of defeating the Unversed once and for all, while Terra loses his body to Master Xehanort after their fight and becomes nothing more than the Linger Will, while the third and final main character, Aqua, defeats the Big Bad, but becomes trapped in the Realm of Darkness.
This leads into Kingdom Hearts, at the end of which Sora is able to restore the worlds destroyed by Darkness and seal the Door to Darkness, at the cost of trapping Riku and King Mickey inside and leaving himself, Donald, and Goofy stranded in an unknown place without the Gummi Ship. Both issues are solved in Kingdom Hearts: Chain of Memories, but Sora loses all of his memories and must be placed in an incubator for a year while Naminé restores them. He and Donald also lose all of their abilities in magic.
And then, there's Kingdom Hearts 3D [Dream Drop Distance], where Sora becomes trapped in a nightmare version of The World That Never Was, and darkness is slowly seeping into his heart. He does manage to defeat Xemnas in the end... only for his heart to shatter, causing Sora to die. But fortunately, Riku revives him. Seems likely that until the series is done and over with, each game will end with a broken arm of some sort.
King's Field II sees the character's father, the former hero and saviour from the first game, get possessed by a demon and release waves of Eldrich Horrors upon the world. Your character must pick their way through this bleak hellscape, and hunt down and kill his own father. Best part - if you fail to get a particular magic sword (obtainable only by sacrificing your one and only friend), then the demon then possesses you. The final narration informs you that peace returns to the land, and life returns to normal... only for your character to slowly fall to the demon and eventually re-release the demons, repeating the cycle - only this time, there's no one to stop you.
Unfortunately, the actual Lost Your Head Trying To Back-Stab The God-Emperor moment was a victim of Bowdlerisation in the international Playstation and all Windows ports—leading to a bit of a What Happened to the Mouse? moment.
Gradius is BUILT on this trope. Congratulations on killing the final boss and blowing it up into a bunch of pieces! Too bad that each of those pieces will regenerate into another Big Bad. Each with their own army.
Venom: I am just a small part of what was known as Venom. Pieces of me are scattered throughout the cosmos. Eventually, another will become sentient and exact retribution. You will never escape the shadow of fear! My hatred for your kind is eternal!
Killing the Bonus Boss of Throne of BaalDemogorgon Prince of Demons is an understandably daunting and challenging ordeal. All this does is free him from his prison in Watcher's Keep and sends him back home to the Abyss. Thanks to the rules governing demons and devils, he will be free to invade the material plane in a hundred years if he feels like it. Defeating it is still preferable to letting it roam free.
In Ghost of Sparta, Kratos and his brother Deimos kill Death. It comes at a terrible price: Deimos loses his life saving Kratos during the battle, and Kratos loses his brother again. Especially tragic since Kratos' goal throughout the game was to save Deimos.
Batman: Arkham Asylum: Batman sprays explosive gel on his glove before decking Titan Joker across the face. But because Batman is badass and will never let the Joker win, never, the "punching out" part actually sticks.
Depending on how you interpret the series, even the good endings mean that whatever malevolent entities surrounding the place just lie dormant until the next schmuck with a Dark and Troubled Past comes around. Then there are the bad endings, where you defeat the Big Bad, but your own sanity has suffered beyond repair.
In Silent Hill 4, Henry is implied to have broken his arm in the good ending.
In Peasant's Quest, Rather Dashing gets burninated after throwing the trogsword at Trogdor.
In Asura's Wrath, Asura breaks his arms defeating the first (and weakest) of the Seven Deities, Wyzen. The final DLC chapter involves Asura defeating Chakravartin, who is essentially God. However, in doing so, he destroys the source of Mantra, meaning that he soon dies, but at least his daughter survives.
In the backstory of the Dead Space series, the few natives of Tau Volantis who hadn't succumbed to the Markers' influence sacrificed themselves to force the Brother Moon into hibernation. In the end of Dead Space 3, Isaac and Carver repeat the sacrifice.
Isaac survives after all, we can hear him breathe and call for Ellie after the credits.
The Awakened DLC reveals that although Isaac and Carver did manage to kill the Tau Volantis Moon, it had managed to awaken its Brethren before dying. And they find out where humanity is and reach Earth before Isaac and Carver can. All of humanity's troubles in the prior games were caused by a single Brethren Moon rendered "comatose" by the Tau Volantis natives... now there are multiple, wide-awake Moons.
Recurrent in Ar tonelico, although the Good End usually involves fixing the side-effects.
In the first game, Mir is initially defeated by singing Suspend, shutting down the tower's systems and crippling Song Magic. Even once the tower is reactivated, large chunks of the land surrounding another tower fall due to the power interruption
In the second, getting into the tower requires dropping half of the already-diminished land area of Metalfass, but upon succeeding with Metalfalica, a new (and much better) Floating Continent is created
In Mahou Tsukai No Yoru, Soujuurou literally breaks both his arms taking out Lugh, an ancient nature spirit in the form of a werewolf. While he succeeds in destroying Lugh's heart, Lugh has a Healing Factor which quickly fixes it. Double Subversion in that while the physical damage is healed, Lugh is left practically catatonic as he comes to the realisation that he can be dealt a fatal blow.
Maxim's battle with the Sinistrals in Video Game/Lufia in the original and Rise of the Sinistrals. He and his party managed to defeat all four of them, but his Love Interest Selan is fatally injured, and Jerin also later lost his eyesight from the battle. Maxim himself wasn't able to escape the Sinistrals' Floating Continent and died with it when it sank into the ocean, with the most he managed to do was break the crystals controlling it to keep it from crashing where it would harm anybody. Worst of all, the Sinistrals weren't gone for good, Erim reincarnated as Lufia, and her mere existence revived the other three Sinistrals. While The Hero in the original game and his party were able to defeat them, his refusal to kill Lufia for good meant that the Sinistrals would return AGAIN, leading into the events of The Legend Returns.
In The Order of the Stick, the Order of the Scribble's attempts at sealing the Snarl may count as this. They successfully manage to patch up the holes in the Snarl's prison with the gates, but one of them dies and the survivors break up for good, with bad blood between many of them. Said bad blood ends up destroying any united plan they may have had for protecting the gates, allowing Xykon to attack them piecemeal.
Further arm-breaking occurs when it turns out their solution to containing the Snarl allows for someone to access and control the power of the Snarl without setting it free, which is essentially the main plan of every major villain in the series.
Sluggy Freelance: The Sluggyverse exists in a Vicious Cycle of creation and destruction. The god of creation, Prozoatu, creates the spark of life, and the god of destruction, Kozoaku brings about extinction events, killing much of it. Kozoaku is technically supposed to do this, but he always does it prematurely, ending the world before he is meant to. Khronus has opposed him many times, but has only ever stopped him at great cost. But for all the trouble Kozoaku causes, killing him would make things even worse, since breaking a pillar of reality will cause a Reality-Breaking Paradox. And since Khronus has become completely indifferent to mankind, a tangle in the malfunctioning Fate Web is going to cause this to actually happen.
Tales of the Questor: Quentyn and his allies manage to kill the dragon they were tracking (a dragon twice the size of the one they thought they were tracking) but at the cost of a broken arm for Quentyn, various bumps and bruises for Sam and Pelinor and Ember (Quentyn's mountain pony) being mortally wounded and having to be put down. Then they find out that the scent of the dead dragon has sent the other dragon (The one they were actually after) into a berserker fury and it sets about torching the countryside. Quentyn and the others are in no condition to even try to fight it and fear the people will blame them for the rampage.
The dragon race becomes pissed at M'Chek's death, starting a thousand world war between Dragons and cubis, and tensions between the races is still pretty strong,
As a result of the above, Cyra's whole clan and family are almost completely killed off, with only Dan, Destania and Cyra herself still alive. Did I mention that since Cyra is the Clan Leader, she is incapable of having other children of her own?
Oh, and Cubi and dragons alike hate Cyra and her clan. No wonder Cyra regretted it.
Invoked inCode Name: Hunter as the main reason why the agency doesn't go to war against the Fey. As explained by Hunter, the Fey are divided in two courts, the Seelie and Unseelie, or Summer and Winter courts. The problem, is that they doesn't just named themselves after the seasons, they AREthe seasons, with their Queens being the living incarnations of Summer and Winter respectively. So, while it's perfectly true that the agency has resources to hunt down and destroy the Fey, they can't do that fast enough to prevent the courts to retaliate and cause climatic disaster of global proportions.
In Draw With Me, it becomes did you just lose your hand trying to punch out Cthulhu (in this case, an instantly regenerating glass wall).
Phase, in the Whateley Universe, fighting a tiny aspect of a demon trying to gain a foothold in this dimension. She stalled it long enough that it could be sealed off again. For now. But she ended up with broken bones, life-threatening injuries, psychological damage and hideous nightmares that required intervention to stop. And, the personal enmity of said demon.
Halloween at Whateley, since killing Sara was the whole point. Not only did it fail, but the two commanders of the force that attacked are now wanted by the criminals as well as the law, and the one who ordered the attack got into deep shit, and a good portion of the attacking soldiers were killed or taken into MCO custody.
Jay from Marble Hornets in Entry #52 tackles the Operator/Slender Man, but in doing so he loses the last seven months from his memory.
Occurs in the Goku versus Superman Episode of Death Battle. Superman manages to completely atomize Goku with the Infinite Mass Punch, but the impact causes the entire earth to be shattered.
The page quote is taken from the Unlimited episode "Divided We Fall", after the titular league knock themselves out in the process of destroying the Doomsday Device of a near Physical GodNanomachine-controlling Brainac/Lex Luthor fusion. The villain, able to rebuild it a matter of minutes and being utterly undamaged, shrugs it off with the above comment. It is then subverted, when Flash taps into the Speed Force and uses it to demolish the villain atom by atom, faster than his nanomachines can compensate.
A much less serious version of this trope happened in "This Little Piggy" when Batman and Zatanna picked a fight with Circe. The two make a fair account of themselves until Circe actually starts fighting back, at which point she reveals that she's just humouring them. Since Circe is a Screwy Squirrel, they manage to talk their way out of further confrontation.
Anything used to try to stop the Beast Planet of Shadow Raiders. Turn your whole planet into an energy gun, the firing of which kills everyone on it? Not even a scratch. Ram it with another planet? It's annoyed. Turn a planet into a bomb and blow it up when The Beast is eating it? Doesn't even get heart burn. The best the heroes do is send it somewhere else, so it just attacks another system.
Something similar happened with Alpha Q's planets in Transformers Energon. When Unicron came to eat their world Scorponok set off a bomb in the center of the planet in order to destroy him, since their own lives were forfeit anyway. Unfortunately the bomb only sent Unicron into a temporary coma, and when he woke up Alpha Q was trapped inside him, alone and slowly going mad.
Transformers Prime has in Stronger Faster, when Ratchet has use synthetic energon to take a level in badass and seems invincible most of the episode, so he gets confident enough to try fighting Megatron, who initially laughs him off as Optimus "pet medic", before Ratchet punches him across the room, but as Ratchet soon learns the hard way, all this did was make him mad, or more accurately, put him in worse than he was already in, and tear Ratchet open nearly cause him to bleed dry from Energon lose. Ratchet survives, but the Decepticons get away with a sample of the synthetic energon with plans to reverse engineer it.
Wheeljack and Ultra Magnus' fight with Predaking, with the two compensating for Predaking's greater strength through their teamwork and managing to land a beating on him before dropping a giant stalactite on him. They thought they killed him, but what they find the hard way is that only gave him a weapon which he nearly crushes Wheeljack with it and then nearly killing Ultra Magnus.
The show's finale Predacons Rising. Optimus Prime manages to permanently stop Unicron but tricking him into opening an empty container that he though contained the All-Spark, which instead leads to the container sucking out Unicron's spark and trapping him. This unfortunately is followed by a reveal that to pull this off Optimus had insert the All-Spark into himself, and to release it back into Cybertron to fully revive the planet, it meant releasing his own spark to join it, costing him his life.
In Gargoyles, the heroes (and anti-heroes) find themselves up at one point against Lord Oberon, ruler of The Fair Folk. They try various weapons against him, which do nothing, until finally hitting him with an iron harpoon that does some serious damage. Unfortunately, even an injured Oberon is stil the most powerful character in the series, and now he's really mad.
Later when he's standing over baby's crib, Fox blasts him with magic. This also actually manages to hurt him. Unfortunately, she has no idea how to do it again, it didn't hurt him that much, and now he's even more pissed.She still saves the day, since Goliath used this display of magic to convince Oberon that Alex's magical potential can be nurtured without taking him away from his family.
A rare villainous example. Admiral Zhao manages to kill Tui, the Moon Spirit. La, the Ocean Spirit, gets pissed, fuses with Aang into an enormous One-Winged Angel, and lays an absolute smackdown on a massive Fire Nation fleet. After Tui is revived via Heroic Sacrifice, La parts with Aang, grabs Zhao, and drags him underwater.
Later in the series, the Gaang is fighting knowledge spirit Wan Shi Tong, who's trying to sink his library and trap them forever so they won't try to use his knowledge to hurt people. Sokka manages to knock Wan Shi Tong unconscious by hitting him over the head with a book. The Gaang barely manages to escape the sinking library with knowledge that can help them win the war. But unfortunately, the library still disappears, Appa gets stolen during the fight, and worst of all, the Gaang's new friend Professor Zei gets dragged down with Wan Shi Tong and the library. Presumably, Zei stays trapped there forever. In the squeal series "The Legend of Korra" it was noted that Professor Zei remained in the library for the remainder of his life as we get a glimpse of his skeleton later in the second season.
At the end of the Teen Titans "The End" trilogy, the Titans prepare to face off against Trigon. The only one who doesn't fight is Raven, who has been reduced to a child, lost all her powers, and is convinced the fight is hopeless. The Titans and evenSlade fight and manage to actually wound him. Unfortunately, this just pissed him off and he quickly defeats Slade, takes down Cyborg, Starfire, and Beast Boy with one shot, and finally even defeats Robin. Their courage and refusal to give up however, leads to Raven taking a level in badass and properlypunch him out.
Honeybees die whenever they sting a human, or anything else with thick skin. They will try to avert this. If they have to give up their life for one tiny attack, they will make sure to make it count. Usually byhaving the whole hive sting you at once.
Eleazar Avaran, one of the leaders of the Maccabean revolt, where the Jews fought for and won their freedom from Seleucid rule. Eleazar killed a war elephant with a spear, but the elephant fell on him and he was crushed to death.
This is also a crowning moment of awesome. Having no idea how to deal with Elephants he ran under the thing when it reared... and allowed it to fall on him, spear planted firmly in the earth.
A national-level version occurred in the dying stages of World War I, with the German Spring Offensive, which let them break through the British and French lines...but their troops got so far ahead of their own supply lines that they simply couldn't sustain the attack and were thus screwed when the British and French made their counterattack, aided by American forces.