Two-Headed Coin

"''The two-sided mint is the rule, not exception,

And would you not feel quite the fool of deception

To find the same face on both sides of the coin?''"

- Drood

A character flips a coin to make decisions, letting their fate be decided by chance... except that they've secretly provided a two-headed coin just to ensure that "fate" comes out in their favor.

A two-tailed coin is equally valid, but much less common, for whatever reason. Additionally, if a coin is being judged on the side that lands and not the symbol, a two-headed coin is actually more fair, as the weight of different designs actually biases normal coins.

Often a characteristic quirk, usually for villains, anti heroes, or badasses. May indicate a character is Two Faced or appear as a Number One Dime. Can invoke Dramatic Irony when the audience knows the coin is rigged, but the other characters don't. When the coin isn't two-headed, it may still always land heads up due to the Random Number God or a character being Born Lucky. Sub Trope of Fixing the Game. See also False Roulette for another type of game of chance that isn't actually up to luck and Heads Tails Edge for other another coin-flipping trope.

Anime and Manga

 * In Digimon Adventure 02, when Hikari is trapped in Full Metal City and Daisuke and Takeru are preparing to reenter to rescue her, Daisuke (who has a crush on Hikari) attempts to pull this on Takeru to decide who will go. He uses a false American quarter with heads on both sides, declaring that heads means Takeru goes home. Takeru swipes the coin while Daisuke is gloating about his "victory" and calls him on it, noting that such false coins are widely sold at a local store.

Comic Books

 * A Subversion is part of Two-Face's signature style in the Batman comics: Harvey Dent uses one of these, but then one side gets scratched up, making it back into a fair coin. Its emotional/symbolic significance to Two-Face makes it a Number One Dime as well. (Originally it was Boss Maroni's "lucky coin", and hence was tied to his origin. In later stories it was the coin his abusive father tossed with the assurance that if it came down tails he wouldn't be beaten. Harvey only learnt it was double-headed shortly before being scarred.)
 * Subverted in Iznogoud, where all the coins are two-headed. Iznogoud forgets it, ridiculing himself.
 * In a Jonah Hex comic, a Frenchman uses a two-headed coin to win a coin toss against Jonah: choosing to stay behind and make the Heroic Sacrifice holding off the Indians while Jonah gets the woman they were escorting to safety.
 * One villain in a Lucky Luke album used a two-headed coin.

Film

 * In Batman Forever Two-Face has his double-headed coin with one side scarred, like usual. It's a Double Subversion, though, as instead of always doing what the coin says, he keeps flipping the coin until he gets the outcome he wants.
 * Used by Jai in Sholay when he and his brother need to make a difficult decision. Needles to say, he always gets his way.
 * The Dark Knight: Harvey Dent uses a two-headed coin for Perp Sweating; he says every time he doesn't get a straight answer, he'll flip the coin. Heads, he asks again. Tails, he shoots him dead.

Literature

 * In one of the Doc Savage novels, Monk gets a two-tailed coin to swindle Ham because he habitually calls heads during a coin toss.

Live Action Television

 * In the Doctor Who story "The Pirate Planet", the Doctor settles an argument with a coin toss, revealing afterward that it's a coin from Aldebaran III, where they have two kings so both sides of the coin are heads.
 * Appears in one episode of Only Fools and Horses; Grandad gave Del Boy a two-headed coin, which he tries to use to win bets with Boycie. Unfortunately, because he tosses, Boycie gets to call, and keeps calling heads. At the end, after Del's beaten Boycie at poker, he offers Boycie double or nothing on the coin, but because Boycie thinks the law of averages means he's bound to lose this time, Del suggests that instead Rodney could call it, as Del's representative. So he spins the coin ... and Rodney calls tails.
 * In Disney's Zorro, Uncle Esteban makes frequent use of a two-headed coin; the locals are gullible enough that he's never caught at it, though Diego recognizes the coin for what it is and realizes Esteban's up to something when he intentionally loses a coin flip to him.

Theatre

 * In The Musical Drood, there's a Patter Song called "Two Sides of the Coin", which is used to lampshade the fact that everyone's playing two roles.

Video Games

 * Used by Dante in the Devil May Cry series. In the second game, he hints that the quirk may come from his father.
 * Dante's coin shows up in his cameo in Shin Megami Tensei Nocturne, where knowing of it lets you get him in your party for a mere 1 macca.
 * Used by Edgar to determine who would rule Figaro in Final Fantasy VI, not so much because he wanted his late father's throne, but because he secretly knew his free-spirited brother didn't. It is later reprised when Celes borrows the coin for a similar flip against the gambler Setzer ("heads, you take us to the Empire's capital city; tails, I agree to marry you.") Setzer is surprised to realize that he fell for a trick coin.

Webcomics

 * Homestuck: Terezi has a two-headed TROLL CAEGAR which, like that of Harvey Dent, has a scratch on one side. In a way, this is still played straight, as both she and those she gambles with know that, thanks to her uncanny grasp of psychology (and being blind), it doesn't really matter which side lands up.

Western Animation

 * Similar to the film and comics examples above, in Batman the Animated Series Harvey Dent uses one of these that gets marked on one side when he.
 * One episode of Tale Spin featured a two-headed coin with a twist: Baloo realizes he's been duped when he notices that not only are both sides of the coin heads, but one of them is making a face at him. Baloo himself had used a two-tailed coin earlier in the same episode.
 * In an Aesop and Son segment of Rocky and Bullwinkle, the son uses a two-headed nickel to win a wagon-full of toys which is not the moral of "Two Heads Are Better Than One". So Aesop tells him a fable of this moral.