Perhaps the mech has a mode inaccessible by the pilot until a specific password is entered. Perhaps the inter-dimensional portal that the characters use for rapid transit is actually a doorway to Hell. Perhaps a certain magic ring can do more than make one invisible.
Often the thing in question was being used by the character in a mundane or straightforward way when untapped potential lay hidden within. Typically that potential is revealed in a surprising way, often by a villain but not always.
At the time that the work is taking place the thing is being used with some regularity, it's just that the current owner/holder is unaware of the thing's other, loftier or more powerful abilities. To clarify, the thing in question serves a purpose outside of its "special" abilities or traits. The sword was being swung, the gun was being fired, and the artifact was being worn for a practical/useful purpose prior to The Reveal
. The reader/viewer is usually unaware of the "true" purpose of the thing, but the character is ALWAYS unaware.
A Super Trope
to Unholy Holy Sword
A Sister Trope
to Chekhov's Gun
, Excalibur in the Rust
(where the thing has been unused prior to The Reveal
), Chekhov's Boomerang
(where the thing is used infrequently, or once and forgotten about then used again, and there's no Reveal)
Compare Plot Coupon
(when obtaining the thing is part of the work's narrative), Plot Coupon That Does Something
(which is more specific to Video Games
), Cerebus Retcon
(which is what the thing becomes retroactively), Sword of Plot Advancement
(where the thing is obtained late in the narrative of the work)
(which serves no useful purpose)
Anime and Manga
- FLCL: Naota and the "beings" that sprout from the portal in his head serve to drive the plot of the series and other narrative roles, but it's only at the end that the true nature of the portal is revealed.
- Initial D: The engine in Takumi's Sprinter Trueno blows up, so he receives a new one. The new engine revs much higher and produces more power than the old one, but Takumi is initially unaware of this and drives the car as he always has.
- Fullmetal Alchemist: Alchemy is widely used throughout the series by protagonists and antagonists alike. It is explained to be a form of Earth energy manipulation. It is only later that the characters learn that Alchemy as they know it is actually powered by an enormous sentient Philosopher's Stone, and gain access to "true" Alchemy by finally tapping directly into the Earth's energy, supercharging their abilities.
- ElfQuest. The main protagonist, Cutter, carries and uses his deceased father's sword, New Moon, continually all through the first book without even a hint that its pommel can be removed and has a key attached and it isn't until shortly before The Palace War in the fourth book that anyone discovers what the key unlocks.
- Red vs. Blue: Tucker finds a sword that turns out is an ancient relic of an alien race and its intended use is a key to reveal an ancient alien ship. Tucker thinks that it's super-lame that his precious sword is really just a key.
- Caboose: No, we came home because the alien died, and because the uh, glowing sword turned out to be a, uh glowing key. Church: Yeah, a glowing key that could still STAB people. Caboose: Right. Church: So it is a sword. It just happens to function like a key in very specific situations. Caboose: Or it's a key all the time, and when you stick it in people, it unlocks their death.
- Soul Calibur: Xiangshua's sword, Krita-Yuga, is actually Soul Calibur.
- Secret of Mana: The rusty sword would be an example where The Reveal happens early in the game, but the player goes through at least the first area and fights the first boss before finding out (unless you read the manual or the intro scroll before sitting down to play). And you still don't find out how to power it up until clearing the next area.
- Persona 4: When the game begins, Social Links are introduced as a way of strengthening Personas and have other purposes, none of them related to the combat mechanic. It isn't until the True Final Boss that Social Links reveal their true power: they represent the combined strength of all your friendships and relationships acquired throughout the game, and are the catalyst for striking the final blow against Izanami.
- Neverwinter Nights: In the Hordes of the Underdark expansion your character possesses the Relic of the Reaper, a mysterious object that is controlled by an entity called The Reaper that effectively saves you from death whenever your HP hits 0 by pulling you into the Reaper's pocket dimension. It is later discovered that the Reaper serves the Big Bad Mephistopheles, the creator of the Relic, and your possession of it binds the two of you. When the Drow that had bound him into her service orders him to kill you, the order to destroy an extension of himself invalidates the binding and frees him to turn on her. With his plan to escape a success, he reverses the bond, trapping you in his realm of the Hells (which the Reaper's dimension is actually an extension of) while he remains free in the mortal plane.
- Mega Man ZX Advent: Model A starts off as a mysterious, amnesiac, but otherwise normal Biometal which the main characters Grey/Ashe use to transform into a "Mega Man". After a fight with Atlas (Mega Man Model F) and taking her DNA, Grey/Ashe suddenly gets struck with a message in their inner thoughts, which hints towards someone behind the whole mess and his plans. Fighting other Mega Men reveals more of this, with the final one (against Vent/Aile and Model ZX) reveals the Big Bad Albert's plan of merging all of the Model Ws together to form Ouroboros and use it to reset the world.
- And most of all, after said fight, Model A learns his true purpose of itself, but it refuses to tell Grey/Ashe about it (though Aile/Vent then lectured them about how they make their own destiny, so as to ease their feelings). And in The Very Definitely Final Dungeon, Albert tells Grey/Ashe what Model A is holding in: that Grey is Albert's backup body, Ashe is his legitimate descendant (as opposed to other Mega Men's genetically altered lineage), and Model A contains his backup plan and a smaller copy of Albert's power with Model W to make its Biomatch Albert's successor... In other words, "Model Albert".