Duels Decide Everything

"Brauno: I hope we don't run into any gang-bangers on the way home.

Onomatopeya: Don't worry Brauno, they usually challenge you to duel first, and they'll leave you alone if you win."

- Yu-Gi-Oh! Animated Duels, "Demonic Duels at Midnight."

In a World where Foo Fu is Serious Business, Conflict resolution often boils down to a Foo-off.

Every problem will inevitably lead to a climactic battle of mah-jong, or Uno, or what-have-you. Is The Hero facing the threat of war? A terrible plague? An economic recession? Inevitably, there's a tangible villain responsible for it and the solution is for the hero to confront them and show them that his Kung Fu is Stronger Than Theirs. If you're watching Tales of the Knights of St. Bob you're probably looking at a swordfight waiting to happen, but it's equally possible that you're watching something like Super Table Football Superstar and after an interminable mutual glare, one party will dramatically challenge the other to a game of table football.

Everyone has absolute respect for the authority of the fu-du-jour to decide who gets to walk away the winner. If the "Foo" in Foo Fu is arm wrestling, after Bob has won and is walking away, Alice will not even contemplate the possibility of shooting him in the back. If it's psychic manipulation and Alice has just won a tiring Battle in the Center of the Mind, it will not occur to Bob to jump at her, pin her to the floor and start punching her in the face. And, yes, even if Bob has just lost a game of table football he will just helplessly stand there, shaking his fist in frustration- because, well, what can he do? He's been beaten in a game of table football. Game over for him, really. The best he can hope for is a rematch. Fighting Alice in any way that doesn't involve table football doesn't cross his mind.

This extends beyond just getting the defeated party out of the picture. If the Big Bad has been bested, their whole evil operation will fold up on itself and disappear within the day. The Evil Army will not rally. There is no plan B. The superweapon The Hero managed to destroy while Storming the Castle will have No Plans, No Prototype and No Backup. It's as if some cosmic force had decreed that this conflict be settled with Combat by Champion. Whether the stakes are trivial or world-shatteringly huge, Duels Decide Everything.

Anime and Manga

 * Ranma ½
 * Yu-Gi-Oh! in all its incarnations. This reaches the point where, in the anniversary movie, the villain tries to go back in time to prevent the spread of Duel Monsters... using Duel Monsters.
 * Which, in a way, is Fridge Brilliance. After all, Yugi's title of "King of Games" suddenly becomes really important when you realize that being the best duelist means you could get away with doing whatever you want.
 * Ironically enough, the original manga series and first anime series subvert this somehow. Yami Yugi had demonic powers which he could use to punish anyone he defeated in a test of luck or skill (including himself, if he lost ). Therefore, the demonic powers are what controls the world (which makes sense, considering they can bend reality), and the duels are just a requirement to activate them. (besides being cooler)
 * Pokémon: Get monsters to fight each other. Small nods through the game and other sources indicate that if someone doesn't have Pokémon to defend themself with (i.e., because the last one just got knocked out), even the weakest Pokémon are very much able to seriously injure or even kill a human.
 * In his first encounter with TeamRocket, Ash tries to engage them in a fist fight. They quickly invoke the trope and state that all their battles can only be with pokemon.
 * Duel Masters
 * The Legend of Koizumi: Mahjong decides the fate of ENTIRE NATIONS!
 * Mobile Fighter G Gundam: Every four years, countries all over the world get to use their shiny new Gundams and send out different fighters to beat the ever living tar out of each other so one country can rule everyone else for four years. It's worked for sixty years, except for that one time where Neo-England decided to invoke Never Bring a Knife to A Gun Fight for three fights straight and nearly brought things to a halt.

Comic Books

 * One Judge Dredd comic included a heavily satirical televised battle between the Soviet and American cities. Each battle is five-on-five, no holds barred, and the winner is awarded a piece of territory. This form of warfare works for a while, but does not prevent a nuclear war later on.
 * Similarly, an issue of Transformers has an ancient Autobot overlord attempt to get two warring city-states to settle their differences through gladiatorial games. As you might expect, it didn't work out as much as he hoped it would.

Film

 * The 1998 Made for TV Movie FutureSport, where the title game was invented as a substitution for gang violence, and ends up being used to avoid a war.
 * The Karate Kid: Battle with karate.
 * In The Luck of the Irish, Kyle tries to trick an evil leprechaun named Seamus McTiernan by betting that he can beat the guy at sports. Seamus agrees (being unable to resist a bet) but chooses "traditional Irish sports" like hurling, step-dancing, wrestling, and javelin-throwing. Surprisingly, Kyle manages to tie the leprechaun, but Seamus insists that a tie is not "beating" him, so Kyle bets his freedom on a game of basketball. Of course, he realizes that he doesn't need the titular luck after all and beats the bad guy.
 * The film Robot Jox is based around a series of mecha battles between the USA and USSR to decide who gets Alaska.
 * Another film with a similar premise involves a mecha battle to the death between a human and a Human Alien to decide the future of Earth. Similar to the Robot Jox example, the hero ends up getting beaten in his Humongous Mecha but still wins by sneaking onboard his enemy's.

Literature

 * In the prologue of Knife of Dreams  has dug up a half-forgotten law that gives him the right to Trial by Combat and which, if he wins, should give him command of an army. Subverted when some of the officers of said army accuses him of blatant Loophole Abuse and try to arrest him. Double-subverted when the Commander is so amused by his cockiness that he lets him proceed as planned.

Live Action TV

 * Back when the Upright Citizens Brigade had their own Comedy Central show, a third season episode centered on a small town which solved their disputes with log-rolling contests, from "Peanut Butter vs. Jelly" up to "Good vs. Evil."

Tabletop Games

 * Changeling: The Lost: The true fae are Reality Warpers so any duel actually does decide everything, Changelings on the other hand are stuck with less powerful versions.

Theater

 * Cyrano De Bergerac: Given that the play is a Swashbuckler, this trope would be expected, but then is averted and invoked
 * Averted at Act I Scene I: there is a duel between gentlemen, but they lampshade is only a passtime and definitely doesn't decide anything.
 * Averted at Act I Scene IV: Cyrano and De Valvert engage in a Sword Fight. This doesn’t decide anything but set Cyrano as the Spanner in the Works for De Guiche’s plans.
 * Invoked at Act V Scene V: Cyrano invokes a Sword Fight with his old enemies (Falsehood, Treachery, Compromise, Prejudice and Folly) and then with Death itself… but Cyrano admits that he has already lost.

Toys

 * In Bionicle, the residents of Bara Magna decide who owns resources by having gladiator battles (which are more like tournaments, rather than a fight to the death.) Justified, since it prevents the villages from going to war with one another.

Video Games
"Kazooie: Huh? If we beat her in a race, she'll call off the plan and leave? Banjo: So she says. I was in a similar situation once before, a long time ago, with a genie and a giant pig..."
 * F-Zero
 * In Monkey Island, Insult "X" contests.
 * Subverted with the Monkey Kombat at the end of Escape from Monkey Island, where it's impossible to either win or lose the fight, as the hit points regenerate faster than they can be drained. The trick is to.
 * The basic plot behind most of the Touhou games: something bad happens, and the protagonists set out to find the ones responsible and Bullet Hell them into submission. The Hakurei Shrine Spellcard Rule System ensures that even in disputes between people with wildly different power levels, non-lethal spellcard battles decide everything.
 * Occasionally, such as in some storylines for Phantasmagoria of Flover View, the battles - and protagonist - don't really decide anything, and the battles only serve to place the player where and when the storyline resolves itself. Losing battles then just means you don't get to see it happen.
 * As virtually any possible plot in the setting could be resolved by getting the right people to come to the right party, proving to the (generally immortal, nigh-unkillable and non-villanous) antagonists that you survive well enough to be worth remembering and befriending may make Duels Decide Everything fairly rational.
 * Custom Robo - Duels with toy-sized robots are shown right at the beginning to be the perfect way to attempt a robbery. It gets more ridiculous from there. It's mentioned a few times that the toy-sized robots use real weapons with live ammunition, operate in bullet time and can be controlled over decent distances (and in Arena one police officer NPC actually does get shot during a fight) -- using them for a robbery makes sense. Dueling with them being their primary use (even when there are safties that vaporize any stray bullets), not so much, and this still doesn't explain how you end up always fighting them in the game's toy arena...
 * possibly averted in that it seems custom robo battles can't be escaped, someone can force you into it, and the victory is absolute, the winner is perfectly fine, but the loser gets knocked out cold.
 * The Tradesmeet subquest in Baldur's Gate 2 that deals with the Shadow Druids can be resolved this way. When you reach Druid's Grove, you can challenge the leader of the Shadow Druids Faldorn. Only a Druid character can fight her; meaning you will have to send Cernd, Jaheira, or yourself (if you are also a Druid). Winning the battle ends the Shadow Druids' assaults on Tradesmeet.
 * In Pokémon everything is decided by pokemon duels. Need to go down a road? Pokemon battle. Need to stop Olympus Mons from rampaging? Pokemon battle. Need to thwart villainous plans? Pokemon battle again! The series have been playing around with this trope lately, though.
 * In Inazuma Eleven, football games solve everything. Early on in the first game you even
 * In the LOGBOX level of Banjo-Kazooie Nuts & Bolts, Gruntilda is about to implement a plan that will cause the whole console to have to be shut down. However, she tells our heroes that she will cancel the whole thing if they just beat her in a race.


 * Justified in League of Legends, where most political disputes are resolved through Combat by Champion with strict rules, a system put in place to prevent the widespread devastation caused by large-scale magical warfare.

Web Comics

 * Misfile street races
 * Lance from GCC whenever he fights Blake, his rival.

Web Original
"Joey: What do you people want from me? Bandit Keith: Your Star Chips, dweeb. I have a score to settle with Pegasus, so Zombie-Boy here is going to beat you in a card game! Joey: ...Why didn't you just take my star chips while I was unconscious?
 * Yu-Gi-Oh!'s tendency to do this is mocked mercilessly by Yu-Gi-Oh the Abridged Series and is a common source of humour:

Bandit Keith: Shut the hell up!"