Villain-Beating Artifact

Welcome to my cave, young adventurous Hero. Here pick one of these two weapons, because at your current level you can't defeat the villain or punching out Cthulhu. He, his mooks, and scientific experiment pet, will defeat you in less than a minute, during the Curb Stomp Battle, if you do not use this weapon.

The first weapon was forge by purest minerals, one of it's special ingredients is virgin tears of joy. This artifact is able to take on and even kill Evil Incarnate itself. Even sealing it.

The second weapon is a whip that's handed down by the legendary vampire hunters, whose heir is lost in history. If you are related to her, this will boost your current spells and strength to be on an equal match with the Big Bad.

Subtrope of Plot Coupon That Does Something. Sister Trope to Sword of Plot Advancement

Film

 * Kubo and the Two Strings: The titular character and his companions must find three weapons, the "Sword Unbreakable," "Breastplace Impenetrable," and "Helmet " in order to defeat the Moon King

Literature

 * In Mistborn. This is double subverted. Since the metals are used in the Magic System, ten are known to bestow powers. Kelsier made rumors of the Eleventh Metal that has powers to defeat the Lord Ruler, when Vin tries to use it, it's shown her intangible images of people who used to be. No Immortal Inertia ensues.
 * His Dark Materials: Subverted this. The subtle knife was claimed several times to be used as the only weapon capable of killing God, the supposedly Big Bad of this series. The knife's owner was encourage to take it to the guy opposing God, so he can win.
 * Gardner F. Fox's "Niall of the Far Travels"'s "Out of the Eons," a short story. Adonair, an alternate universe evil deity, tries to enslave humanity and conquer the world. The gods can't destroy him but manages to trap him. Niall accidentally releases Adonair at the story's beginning. The only way to get rid of Adonair is for Niall to drink a special liquid and trick Adonair into possessing his body.

Live-Action Television
"Dean: "So, you need one sword to kill one dragon, but you got to kill one dragon to make one sword. How does this work out?""
 * Supernatural
 * Samuel Colt made a special Colt gun and bullets. This gun can be used to kill almost anything. - Except Lucifer.
 * There's a special dagger which can kill demons (and the humans that they possess at the time). Regular knives and daggers don't work, it's just the host body. It's backstory has yet to appear.
 * In one episode, the dragon can only be killed by a sword that's forged by the blood of another dragon.


 * In Buffy the Vampire Slayer had some of these moments - Like Thor's Hammer, that's used to whomp Glory down to size.
 * Doctor Who: Subverted. In one episode, "Last of the Time Lords." Which has Martha Jones spending a whole year searching for a weapon which was separated into four parts that can defeat the Master, revealing at the end that the Villain-Beating Artifact
 * Once Upon a Time twisted this trope. The only way to defeat the Big Bad is to steal his dagger,

Video Games

 * In Grow RPG, this trope was distilled down to its molecular essence. Besides the sword and armor, you will need the special blue orb which can knock the Big Bad's life meter down to where you can go man to man. (It's not possible to reach the Big Bag without it).
 * In Chrono Cross, you can kill the Time Devourer using force alone, but it'll come back eventually. The only way to defeat it once and for all is to use the Chrono Cross.
 * God of War, whatever is contained within Pandora's Box has power that capable of killing a god (Hint: It's the only thing). So Kratos spends the first game to find and open the box, that way he can off Ares. In God of War 3, he needs it again to defeat Zeus...
 * Warcraft 3: Not a specific weapon, but mainly a damage type. Divine armor's weakness is Chaos, which is reserved for Hell's legions or insanely strong monsters. In order to defeat, Cenarius, an invulnerable demigod, Grom Hellscream's orcs reactivate some sort of demon pact, this allows them to defeat him (By giving them Chaos damage).
 * Neverwinter Nights 2, the only way to injure and even kill the King of Shadows, was to find the Silver Sword of Gith. But it was broken into several shards when it was used earlier and your character ain't the only one interested in collecting them.
 * In the original Doom 3, the player uses the Soul Cube to defeat Cyberdemon. The smaller ones, however, aren't limited to this type of weakness. Also, the Soul Cube powers up by using the souls of fallen enemies. Subverted, in patches.
 * In Legend of Zelda, most of the games, has Link needing the Master Sword to defeat Ganon.
 * In the Phantom Hourglass, Link needs the Phantom Sword to defeat Bellum.
 * Also, the Silver Arrows.

Western Animation

 * Samurai Jack, the titular character's sword is the predominately the only weapon to take out Aku, because of its Made of Good.
 * In Adventure Time, the gauntlet that Billy owns has the power to seal the Lich.
 * In Scooby Doo Mystery Inc, Scoob and his friends found out that they need to find and use the Heart of the Jaguar to destroy During the final episode,