History Main / CosmicKeystone

* ''VideoGame/{{Darksiders}}'': The Seven Seals are essentially a countdown to Armageddon. Breaking the Seventh is the signal for everybody to engage in the massive cosmic winner-take-all power struggle that is the End War, with the Horsemen ready to clean up the mess when everything is resolved. [[spoiler:Abaddon starts the plot of the game by deciding to break all but the Seventh Seal in order to prematurely start the End War ''without'' getting the Horsemen involved in the hopes of wiping out Hell's generals in a first strike and finishing the War before it really starts in favor of Heaven, while also getting them repaired in order to claim Hell struck first and Heaven just punished them. Unfortunately for him, Hell anticipated this and launched a full invasion from the get-go rather than the probing attack he was expected, and the Charred Council ''knew'' about this all but let it happen because they wanted humanity wiped out and even engineered War to answer the call of the broken six seals alone so they could string him up as a scrapegoat and use him as a vengeance-seeking pawn to wipe out the loose ends.]]

** Gallifrey itself may be full of these, not least of which are the Eye of Harmony and [[EmpathicWeapon the Moment]]. It is taken quite seriously that the [[SufficientlyAdvancedAliens Time Lords]] could end the universe if they chose to do so, using technology they already possess.
** [[Recap/DoctorWhoS28E3SchoolReunion "School Reunion"]] features an equation that can "solve" the universe, and somehow rewrite it to suit the solver's needs. The Doctor has to decide whether or not to use it to bring back the Time Lords and stop the Time War from happening. [[StatusQuoIsGod He]] [[TheWoobie didn't.]]
* ''Series/{{Lost}}'' [[spoiler:The Heart of the Island, from which emanates "life, death, and rebirth." Conflict has existed for centuries between those that would protect it and those who would use it for their own purposes.]]

* ''Series/SeaQuestDSV'': Done in a slightly harder SF context. A deforested future Earth depends on ten massive air processing plants to keep what's left of the planet livable. Then a race of genetically engineered SuperSoldiers -- with lower oxygen requirements -- decide they wouldn't mind the place to themselves...

* ''VideoGame/WildARMs'' has the Tear Drop -- a crystal with a link to the guardians and should not be in the wrong hands. There's also the Ray Line, a sort of underground conduit linking the guardians' powers. When the villains manage to damage it, the forces of nature go out of whack, wreaking havoc. And this makes more sense if you take into consideration BlindIdiotTranslation: Ray Line = ''{{Leyline}}''. Indeed, it was translated as Leyline in the [[VideoGameRemake remake]].

* The plot of ''VideoGame/RatchetAndClankFutureACrackInTime'' revolves around the Great Clock, a massive space station built in the exact center of the universe (Give or take fifty feet). Long ago, misuse of time travel almost caused a RealityBreakingParadox, so the Zoni built the Great Clock to maintain the universe's structure, akin to a cosmic pacemaker. The game's villains believe that by controlling the Great Clock they can use it as a TimeMachine and change history as they want.

* ''Franchise/TheDarkTower'' in the series of the same name. It manifests in all worlds, but only in one does it appear as an actual tower -- which is held up by six radiating Beams that span the sky in twelve directions from it. In most worlds, it takes the form of a rose, though it has also been known to appear as a tiger, a dog, or a talisman. Long and short of it is that all worlds are connected to the Tower, and the destruction of the tower is all it takes to bring everything down. In an interesting twist, two ''entire universes'' function as Cosmic Keystones for TheMultiverse. One is the world in which the Tower exists as a real tower, and in which most of the characters' adventures take place. The other is (''almost'') our world, in which their adventures are described in a series of books by Stephen King -- actually referred to as the "Keystone World", and the only one for which time travel is impossible. Destroying the Tower in either of these universes would lead to all of God's (er, "Gan's") creation being unraveled.