Alfred: Well, perhaps our cowled friend can persuade him otherwise.
Bruce: It's not that easy, Alfred. He's after Batman as well.
Alfred: But why?
Bruce: He fought Bruce Wayne and Batman. Fighting styles are like fingerprints. Kyodai knows that we're the same man.A lot of people hide their identities. A lot of those people do so because they're doing dangerous things. Like fighting. Of course, stories are only interesting where there's risk and drama and junk. One way to introduce some drama is to let someone figure out the hooded vigilante's secret. If you don't want to have the hero lose a fight and get unmasked, or do something stupid at a crime scene, there are other options. One of those is to have an opponent face or observer the hero fighting both in and out of the mask, and from that realize that they're the same person. There's some truth to this. Fighting is one of those things you don't have much control over, so it's not like you can lie about the way you fight. However, fighting's a lot like dancing. It may come in different styles, but they're all working toward the same goal. It's not a fingerprint; it's a blood type. Still and all, it works for the story. This is a less meta-y trope than Tell Me How You Fight. Indices: Combat Tropes, Skills and Training Tropes (What You Know)
--Day of the Samurai, BatmanTheAnimatedSeries
Anime and Manga
- In Sailor Moon episode 100 (dubbed as "Individual Happiness"), Sailor Venus battles the Monster of the Week in a one-on-one game of volleyball -- the ball is an energy sphere protecting the Pure Heart Crystal extracted from the monster's victim. In the climax of the fight, Venus makes a diving save that the half-conscious victim recognizes as the exact move that Venus performed earlier in her civilian identity.
- Mobile Suit Gundam Wing Endless Waltz: Heero recognizes he's fighting Trowa when he recognizes his tactic of excessively firing all of his weapons at him.
- Shingeki No Kyojin: Annie's ruthlessly efficient fighting style is unique. Because of it, Armin uses it as evidence that she is the Female Titan, and after she taught it to Eren, he manages to pull one over Reiner in their fight.
- Mobile Fighter G Gundam: Domon figures out that a cloaked stranger is actually Master Asia after he uses a piece of cloth for a weapon and strikes his signature pose.
- In 52, Renee Montoya realizes that Batwoman is her ex-girlfriend Kate Kane because she uses the exact same punching technique (in addition to the other clues.)
- In Sherlock Holmes A Game of Shadows, Holmes deduces the identity of Moriarty's Dragon, Sebastian Moran, thanks in part to the latter's Improbable Aiming Skills. Moran can hit a target at a 650 yard range in a 7-8mph wind; there are only half a dozen marksmen in Europe with enough skill to shoot accurately under such conditions, and only one of those men served the British Army in Afghanistan and smokes the same brand of Afghan tobacco as Watson (Holmes finds a discarded cigarette at the scene of an assassination Moran carried out).
- Played with in the Wachowskis' Speed Racer. Speed suspects Racer X of being his Long-Lost Relative Rex, because Racer X drives in the same distinctive way Rex did.
- This is a plot point in the movie Undefeatable. The main villain (a Serial Killer who gouges out the eyes of women who resemble his estranged wife) practices a hybrid fighting style. The main character attacks a rival gang because she recognises one of the styles he used on one of the victims as the one they use.
- In the Harry Potter series, the Expelliarmus Spell is this to Harry. Becomes a bit of a problem when he is supposed to be hiding behind several people disguised as him, because it help the Death Eaters to recognize their main target.
- Helena Bertinellia identifies Oliver Queen as the Hood on Arrow after fighting the Hood in one scene and watching Oliver fight in another.
- In the Burn Notice episode "Comrades", Michael Westen (in one of his narrative spy tips) talks about the importance of knowing different fighting styles and remembering which one to use depending on your cover. In the episode he was posing as a Russian Mafiya mook and so had to use a fighting style called Sambo.
Narrator!Michael: A fight is one of the quickest ways to tell if someone isn't who they say they are. If you say you are Russian but fight like an American, consider your cover blown, which means you better know Sambo, the mixed martial art of Russia. Of course, you also have to win the fight; a great cover ID doesn't help much if you're dead.
- In the Champions system, the ability to do this is called "Analyze Style."
- Fire Emblem Path of Radiance: Greil immediately identifies the completely anonymous Black Knight as one of his former students after exchanging blows and hearing his manner of speech. Ranulf identifies him after fighting him in costume and out of costume, and also acknowledges his scent. Ike after being told about his identity confirms it after clashing with him out of costume and claims it makes perfect sense in hindsight because their fighting style is identical.
- Kingdom Hearts II: When Sora faces "Ansem" completely concealed in an Organization Black cloak, he's able to guess that it's actually Riku based on fighting style and signature weapon.
- In this Order Of The Stick strip, Roy correctly guesses that the warrior the Order is fighting is not Thog, but is actually an imposter, by observing his fighting style. Amongst other things, the imposter relies on defence and counter-attack in contrast to Thog's offensive fighting style, and he also leads with his other foot.
- Avatar: The Last Airbender: This is the problem with bending powers. They can only be mastered by the people of the Elemental Nation corresponding to them, meaning that if you use for example waterbending, you're sure to be recognized to be a member of the Water Tribe. This applies especially to Aang, who (as the title of the series suggests) is the last airbender, so if he uses his powers, everyone can figure out that he's the Avatar.
- Sym-Bionic Titan had a situation like this. One of the team's acquaintances had a fighting style distinctive to the royal guard of Galaluna.
- Teenage Mutant Ninja Turtles (2012): Michelangelo befriends a famous martial artists and learns one of his secret katas. When Splinter sees the move he immediately deduces that whoever taught Michelangelo must have been trained by the Foot Clan because it comes from his arch rival Shredder's fighting style.
- In the Batman: The Animated Series episode "Night of the Ninja," the titular ninja figures out that Bruce Wayne is Batman after fighting him, because they both studied martial arts under the same master in the past and had fought before.
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