The Day of Reckoning

""It's been a long journey and no one is coming out without scars. But it all comes down to this moment. We win or lose it all in the next few minutes. Make me proud. Make yourselves proud.""

- Commander Shepard, Mass Effect 2

There are tons of dark prophecies of doomsdays and master plans that take a long time to put into action. The Day of Reckoning is the day that all the prophecies speak of... the day that the Evil Overlord wins, goodness and mercy are overthrown, and a new Dark Age arises on Earth...

At least, until the hero shows up, defeats the villain, saves the day, and returns everything to normal (usually with one or two characters sacrificing themselves to do it). This trope is about the final confrontation between the heroes and the coming evil. The long-awaited and foretold apocalypse. When the heroes finally get out from under the Darkest Hour and put a stop to the villain's plan for world domination.

A specific type of story Climax. See also Darkest Hour.

Anime and Manga

 * Puella Magi Madoka Magica: The Walpurgisnacht.
 * Digimon had the arrival of Myotismon be "The Hour of the Beast" or 6 seconds past 6:06 PM.
 * At the end of Fullmetal Alchemist manga/ Brotherhood, this pretty much happens when Father takes the lives of everyone in Amestris, only to have Ed and everyone else fol his plans, and he was eventually defeated.

Film

 * Star Wars: The day Emperor Palpatine takes over the Republic, beginning with the murder of all the Jedi, at the end of Revenge of the Sith.
 * The Frabjous Day in Alice in Wonderland.
 * In the 2009 Star Trek film, Nero describes his attacks on Vulcan and Earth as the Federation's "Day of Reckoning".
 * Gozer's arrival on Earth in Ghostbusters would almost certainly have been this. Judgment Day is even referred to by name and place in the Bible.

Literature

 * The Battle of the Five Armies at the end of The Hobbit.
 * The Battle of the Black Gate near the end of The Lord of the Rings, used to divert Sauron's attention so that Frodo can do his job.
 * The Battle of Hogwarts, in Harry Potter and the Deathly Hallows.
 * The poem Dream of the Rood briefly speaks glowingly of the Second Coming of Christ.
 * The Dark Forest invasion in Warrior Cats, which is spoken of in several prophecies, and had been built up for most of the series.

Live-Action TV

 * Dollhouse is notable in that it's day of reckoning goes ahead despite (or possibly because of) the heroes intervention. Other than that, it plays this trope to a T.
 * When Angel and his team finally attack the Circle of the Black Thorn and try to avert THE apocalypse.
 * The new Doctor Who series had a Day Of Reckoning at the end of every season. The Doctor refers to them as "Volcano Days". Of particular note are the episodes "The Sound of Drums"/"The Last of the Time Lords", "The Stolen Earth"/"Journey's End", and "The End of Time".
 * Any of the Apocalypses from Buffy the Vampire Slayer.
 * In Supernatural, we have the episodes All Hell Breaks Loose where the brothers finally take out Azazel, the demon that killed their parents... but are too late to stop him unleashing his demonic army into the world; No Rest For The Wicked where the brothers attempt to take out the demon's new leader, Lilith, before she can claim Dean's soul and drag him to hell... and they fail, with Dean suffering a particularly nasty death; Lucifer Rising, where the brothers attempt to stop Lilith from freeing Lucifer... and it ends badly, with Sam accidentally freeing Lucifer himself. Then there's the big one, Swan Song, where the brothers have to re-imprison Lucifer before he can fight Micheal, ending the world... they succeed! (Although Sam is sealed in Hell along with a very pissed-off Lucifer and Michael)...

Religion and Mythology

 * Judgment Day, as described in the Book of Revelation. This makes this trope Older Than Feudalism.
 * While the judgment before the great white throne is literally a day of reckoning (since "reckoning" in this sense is synonymous with "judgment"), the battle of Armageddon corresponds more closely to the trope meaning. The good guys have already won by the time Judgment Day comes around.
 * Ragnarok, the prophesied final battle between the gods and Jotun in Norse Mythology.

Tabletop Games

 * Call of Cthulhu (tabletop game) adventures
 * Shadows of Yog-Sothoth - The rise of R'lyeh and release of Cthulhu. 'Nuff said.
 * Masks of Nyarlathotep - The opening of a Gate that will allow Cthulhu Mythos entities to enter our world.
 * The Fungi From Yuggoth - Dholes will be summoned worldwide, the Sphinx will be changed into an avatar of Nyarlathotep and terrorists will overthrow national governments, allowing the Mythos to take over the world.

Video Games

 * The Final Day from The Legend of Zelda Majoras Mask.
 * The Warcraft series had this with the invasion of the Burning Legion, though they've tried and failed three times already. Rumor has it, though, that they're at it again.
 * In World of Warcraft, the climaxes of both Wrath of the Lich King and Cataclysm in the Icecrown Citadel and Dragon Soul raids respectively. It isn't so much that the villains are planning anything specific at that particular time, but with so many of the allied forces on the line, they'll be home free if the heroes fail.
 * The Mass Effect series has one of these at the end of each game: in the first game, it is the defense of the Citadel and in the second, quite predictably, the Suicide Mission (see the opening quote). The entire third game is more or less an extended one of these, and the assault on Reaper-held Earth serves as an internal example within that.
 * The Day of Lavos from Chrono Trigger.
 * This is practically Black Doom's catchphrase in Shadow the Hedgehog.
 * In God of War III Kratos at last brings fourth the destruction of Mount Olympus, and the gods upon it, as all was foretold.

Western Animation

 * Trigon's invasion of Earth in Teen Titans.
 * Sozin's Comet triggers this in Avatar: The Last Airbender
 * Also the Day Of Black Sun, in a sense—it was supposed to be the allies' day to strike at the Fire Nation, but Azula discovered their plan beforehand and they were resoundingly crushed (except in Omashu).
 * In Transformers: The Movie, the coming of Unicron.
 * The two-parter Second Season finale of X-Men: Evolution is actually titled "Day of Reckoning." It involves the iconic X-Men figure of a Sentinel being let loose in the city and attacking all mutants and them having to defend themselves, leading to their existence being revealed on national television.
 * The two-parter series finale "Ascension" probably also counts, as the titular heroes fight against and defeat their ultimate enemy Apocalypse, who had been prepping up for the last two seasons to turn all of humanity into mutants.