"I'll get paid for killing, and this town is full of people who deserve to die."
Yojimbo — more correctlyYōjinbō, meaning "bodyguard" — is a 1961 Jidai Geki film directed by Akira Kurosawa, loosely based on Dashiell Hammett's novel Red Harvest. It stars Toshiro Mifune as wandering rōnin Sanjūrō, who arrives in a town beset by criminals and decides to clean the place up (apparently for fun and profit). His method is simple, yet clever: he reduces the number of gangsters in the town by getting the two rival factions to go to war, then mops up the remainder. An enormously influential film, it has had at least two direct remakes — Sergio Leone's A Fistful of Dollars, and Walter Hill's Last Man Standing — as well as homages in numerous other films and television shows. It was even used as the basis of an episode of the Pokémon anime.
Yojimbo provides examples of the following tropes:
Badass Boast: Recently recovering from an injury, Sanjurō was out to rescue the innkeeper Gōnbei from Unōsuke's gang. When the sympathetic coffin-maker expressed doubt at the odds against him while he has a mere knife to fight with, Sanjurō bellows: I'll turn them into sashimi!
And earlier when he goes to rescue Nui, he goes into the house where she is being kept under guard and then comes back out to tell Inokichi that all six guards are dead. After Inokichi leaves, one of the guards comes out to see what all the noise is. Sanjūrō wasn't a liar for long.
And the coolest one of them all:
"I guess there is no cure for stupidity except for death."
Bad Cop/Incompetent Cop / Dirty Cop: The local constable is useless and venal, and attempts to get a finders fee for recommending that Sanjūrō join one side of the gang war. Sanjūrō tells him to kill himself at the end of the film.
Sanjūrō: Go hang yourself.
Batman Gambit: Sanjūrō is able to destroy the two rival gangs by exploiting their leaders' personalities and the fact that both of them desperately want his skills.
Character Tics: Sanjūrō has a habit of keeping one hand inside of his clothing and twitching his shoulders. The idea behind this is that he's like a wolf/dog and has fleas — making him a character with ticks.
Chekhov's Skill: Sanjūrō shows he's a crack-shot as a knife thrower by passing the time throwing a knife at a shred of paper blowing around in the wind. It helps him to defeat Unosuke, the gun wielder.
The Ditz: Inokichi doesn't even know how to count with his fingers. He later helps Sanjūrō escape from Ushitora's gang, involuntarily.
Don't Make Me Destroy You: Sanjūrō warns three mooks that mocked him earlier. Said mooks are all sentenced to death if caught and seem quite proud of it. Sanjūrō has thus no qualms and slays them all as a demonstration of his skills and utters the following badass line.
Sanjūrō: Cooper, two coffins... No, better make that three.
Made of Iron: Averted Trope, after Sanjūrō is beaten up and guarded by two of Ushitora's thugs and one of the guards asks the other if it's all right to keep him tied up while the Giant Mook says he's nothing without his sword anyway in a way that would rather seem to be Tempting Fate to many Genre Savvy viewers, Sanjūrō escapes through more sneaky means and drags himself to his escape from being unable to stand.
Master Swordsman: Sanjūrō, naturally. It comes back to bite him when Unosuke notes that he's the only one skilled enough with a sword to kill six men single-handed.
Also, at the very beginning of the film, he chances to see a farmer boy quarreling with his parents; he intends to join one of the gangs, thinking that the excitement and riches are preferable to a boring life of farming and eating gruel. Near the end of the film, Sanjūrō actually has that same farmer-turned-gangster at swordpoint. Rather than cut him down, though, Sanjūrō just remarks to him that perhaps the gruel-eating life is better than this. The boy, elated at this mercy, runs off.