History Main / ThereCanBeOnlyOne

* ''Film/{{Highlander}}'', the [[TropeNamers trope namer]] itself, has immortal beings which can die only by decapitation, killing each other until the last one standing obtains all knowledge of the world and the right to spend the rest of their life as a mortal.

* ''{{Series/Highlander}}'', the TropeNamer along with the films.

* ''WesternAnimation/AquaTeenHungerForce has [[http://video.adultswim.com/aqua-teen-hunger-force/nice.html this bit]].

* In the ''WesternAnimation/RickAndMorty'' episode "Mortyplicity" it's revealed that Rick made a series of RidiculouslyHumanRobots as [[BodyDouble "decoy families"]], which then end up killing each other believing they're the real ones. "Rick" refers to the phenomenon as an "[[Creator/IsaacAsimov Asimov]] Cascade" and references ''Highlander'' during his explanation, [[PopCulturalOsmosisFailure before expressing disappointment that no one else saw it]].
* Drax in ''WesternAnimation/GuardiansOfTheGalaxy2015'' states that there is only one "Destroyer", and it is him, not an empty suit of armor. Drax quotes this trope during his battle with the Destroyer Armor in episode 13 "Stuck in the Metal With You".

-->-- ''The ArcWords of Franchise/{{Highlander}}''

* One advertisement for ''VideoGame/WorldOfWarcraft'' features Creator/OzzyOsbourne himself claiming that "There can be only one Prince of Darkness!"

* This is a reoccuring theme in ''Literature/ASongOfIceAndFire''.

** ''VideoGame/DigitalDevilSaga'' had a concept similar to this, with indiviuduals replaced by entire tribes fighting each other for dominance. When a tribe's leader is defeated, the remainder of the tribe must swear loyalty to the victor, and this continues until only one tribe remains. The winning tribe then gets to ascend to Nirvana. This also stays true for [[Literature/QuantumDevilSagaAvatarTuner the novels]] as well.

* ''VisualNovel/KajiriKamuiKagura'', the third game of the ''Franchise/ShinzaBanshouSeries'' (which is most known for ''VisualNovel/DiesIrae'') has the Hadou Gods. Constantly expanding sentient cosmic forces, who will devour each other until only one is left to become the Godhead, should they ever clash against each other.

* ''VisualNovel/KajiriKamuiKagura'' has the Hadou Gods. Constantly expanding sentient cosmic forces, who will devour each other until only one is left to become the Godhead, should they ever clash against each other.

-->'''Girl 1:''' (''stabs Girl 2'') [[VoiceOfTheLegion THERE CAN]] BE ONLY ONE.

* ''LightNovel/{{Baccano}}'': While not explicitly stated in this is originally Szilard's and Czes's goal regarding their fellow immortals. The former was addicted to [[ForScience science]] and spinal fluid. The latter was a DoUntoOthersBeforeTheyDoUntoUs sort of guy. The rest have gone into hiding and become extremely paranoid of other immortals because of it. in the anime. In the novels, Maiza refuses to tell anyone else the formula for immortality due to an epiphany he had while imbuing his brother with the knowledge that the demon's rules encourage a "There can be only one" situation due to the paranoia of being devoured by their fellow immortals. Excluding the 1930's generation, he was mostly correct. Without exception, all 3 known times that [[spoiler: Ronnie]] has granted others immortality, one has always gone crazy and attempted to devour the rest (only the 2nd (the 1300's immortals) and 3rd times (the 1700's immortals) have been detailed, the first was only mentioned in passing in the novels when he lamented at how quickly they always turned. [[note]] (In the Novel Szilard's goal is only to allow people who worship him unconditionally as a god to be immortal and create an eternal kingdom that fawns over his every desire (he was regretful that he devoured Barnes since Barnes was the exact sort of fanatic that he WANTED to exist, and had let his anger over losing the formula yet again get the better of him) [[/note]]

** It's ''really'' only one because [[spoiler:humans can't touch the Grail, so the Servant does it. Then ''they'' get sucked in and turned into fuel like the others for the wish of the Master. By this point, nobody really remembers the mechanics of how it works anymore because no one's ever won. Well, technically [[LightNovel/FateZero Kiritsugu]] won the last one, but that didn't count.]]

* Spoofed in the ''Franchise/HarryPotter'' parody comic ''[[http://piratemonkeysinc.com/ms1.htm House Sparklypoo]]''. The members of the titular house discover to their horror that they're losing their specialness. Their teacher suggests that it's because each of them is supposed to be the best, but obviously only one person can be the best at anything. Cue massive throwdown as the Sparklypoos try to kill one another in order to regain their special powers, culminating in the destruction of Sparklypoo Tower by an errant [[{{LightNovel/Slayers}} Dragon Slave]].

* In ''ComicBook/{{Supergirl}}'' story ''Fanfic/HellsisterTrilogy'', Supergirl and Satan Girl fight each other for the last time. Supergirl offers to help her evil counterpart find her missing child if Satan Girl stops fighting, but Satan Girl rebukes they're doomed to fight until there's only one left.

-->'''Remoni-Notra:''' "I congratulate you on your victory, Green Lanterns. Nonetheless, I must prove my claim to the crown, as is our custom, by combat."\\
'''John Stewart:''' "Now, wait a minute. This woman's just been through hell and a half. You can't expect her to just get up and fight you like that. I don't care what kind of customs you've got. You do that, and we're gonna show you an old custom from my old 'hood--the gang fight."\\
'''Carol Ferris:''' "It is the tribal custom, John. There are four Star Sapphires in each generation. They battle until all but one is defeated. The one who remains is the true Star Sapphire. By their law, I am required to... to fight her."

--> '''[[spoiler:Sentinel Prime]]''': [[AGodAmI We we're gods once, all of us!]] But here, there can only be one!

* Heartwarmingly subverted in the high jump at the 2020 Olympics. The two top scores, posted by Mutaz Essa Barshim of Qatar and Gianmarco Tamberi of Italy, were identical, so the officials were prepared to stage a jump-off to break the tie for gold, but Barshim and Tamberi, who had been close friends for many years, [[https://youtu.be/GjSCT97GSsA?t=235 told the officials they didn't want the tie broken]] and asked if the rules allowed for them to both win gold. The official told them that it was allowed as long as both of them agreed to it; at that point, all the pair had to do was look at each other and both of them knew they were in agreement. The pair were later seen holding hands on the medal platform as they received their gold medals.

* ''How I Won The War'' has a variation on this. When people are killed, they became a coloured (meaning they turn into red, blue, green etc.) version of themselves, but still can help. Only the main character survives at the end.
* In the (not nearly as awesome as it sounds) film ''Film/TheClonesOfBruceLee'', a MadScientist gets some DNA from the recently deceased Creator/BruceLee and makes some clones. Eventually he plans to TakeOverTheWorld. But for some reason his method of doing so involves only creating three Bruces, and then having them fight to the death because he only wants the best one.
* ''Film/TheKillingRoom'' (2009). Four subjects are locked in a room for a psychological experiment. They're then told only one can get out alive.
* The whole point of Kingsman training in ''Film/KingsmanTheSecretService''. The Kingsmen begin with eleven candidates and then put them through [[TrainingFromHell more and more rigorous training and tests]] until only one is left. This person is then inducted into the agency, because it’s now obvious that pretty much whatever is thrown at them, they can handle it.
* The prisoners in ''Film/BreathingRoom'' are eliminated one by one as they either kill each other or are eliminated for not having discovered why they are there.

* ''Film/{{Circle}}'': The people in the room can't choose themselves, only other people, meaning there will be a single survivor after the elimination process has run its course. However, as someone points out later, when it comes down to the final two, it will inevitably be a MutualKill unless one person sacrifices themselves by not voting.

* ''TabletopGame/YuGiOh'': There's an aptly named Continuous Trap called [[https://yugioh.fandom.com/wiki/There_Can_Be_Only_One There Can Be Only One]] which prevents both players from controlling more than one monster of each type on the field. There are also other similarly restrictive Continuous Traps like Rivalry of Warlords and Gozen Match, although the latter focuses more on the monsters' attributes rather than their types.

* In ''Series/SquidGame'', the contestants discover that the price for failing a game is death. And eventually they come to realize that there can only be one winner for the 45 billion won, as a husband and wife team learn to their horror...

* ''Music/UltimateShowdownOfUltimateDestiny'': The chorus of the song states that "only one will survive". As such, The Ultimate Showdown goes on until only one combatant is left standing.

* ''UltimateShowdownOfUltimateDestiny'': The chorus of the song states that "only one will survive". As such, The Ultimate Showdown goes on until only one combatant is left standing.

* ''UltimateShowdownOfUltimateDestiny''! "Good guys, bad guys and explosions / as far as the eye can see / And only one will survive / I wonder who it will be.."]]

[[folder:Film]]

* ''VideoGame/NoMoreHeroes'' revolves around Travis Touchdown, 11th best assassin in the United Assassins Association, working his way up the rankings by killing off the top ten one by one.
** Though one of the series's themes, which started near the end of the first game and is rampant through the second one, is that there will always be more assassins coming up from behind, so there will never really ''be'' "just one".

** [[spoiler: When Big Boss reappears]] in ''VideoGame/MetalGearSolid4GunsOfThePatriots'', he says "The world needs only one... [[spoiler: No, the world would be best without Snakes."]]

* ''VideoGame/TeamFortress2'': If one melee-equipped Demoman defeats another such "Demoknight," he will sometimes scream "[[LargeHam THERE CAN BE OOOOOONLYYYY OOOONEE!]]... [-[[EyepatchOfPower Eye]]-]."

* ''Film/HowIWonTheWar'' has a variation on this. When people are killed, they became a coloured (meaning they turn into red, blue, green etc.) version of themselves, but still can help. Only the main character survives at the end.

* ''TabletopGame/YuGiOh'': There's an aptly named Continuous Trap called [[https://yugioh.fandom.com/wiki/There_Can_Be_Only_One There Can Be Only One]] which prevents both players from controlling more than one monster of each type on the field. There are also other similarly restrictive Continuous Traps like Rivalry of Warlords and Gozen Match, although the latter focuses more on on the monsters' attributes rather than their types.

* * ''TabletopGame/YuGiOh'': There's an aptly named Continuous Trap called [[https://yugioh.fandom.com/wiki/There_Can_Be_Only_One There Can Be Only One]] which prevents both players from controlling more than one monster of each type on the field. There are also other similarly restrictive Continuous Traps like Rivalry of Warlords and Gozen Match, although the latter focuses more on on the monsters' attributes rather than their types.