You know Advent Calendars? Those things where you get a little piece of chocolate, or a toy, or even just a picture, once a day from the first to the 24th of December?
[[http://www.fanfiction.net/s/8731849/1/ Advent Crossover Crisis]] is one of those, if instead of chocolate, [[DisSimile it was fictional characters kicking the stuffing out of each other]].
An introductory explanation was uploaded to Fanfiction.net on the 24th of November, whereby [[DeadPool Deadpool]] [[MarvelComics and]] SheHulk gave a rundown of the basic facts of the story. The first true chapter was published on the 1st of December, [[CaptainObvious as you can imagine]].
It contains over 30 fandoms, depending on whether you count things like ''VideoGame/SuperSmashBros'' and Franchise/DisneyAnimatedCanon as one piece of fiction, or several. Franchise/SlyCooper serves as the closest thing the story has to a "main character", while [[Disney/SleepingBeauty Maleficent]] is its BigBad.
!!This fanfiction provides examples of:
* ActorAllusion: When [[Disney/ThePrincessAndTheFrog Dr. Facilier]] gives [[RedVsBlue Caboose]] a VoodooDoll he promptly names it [[BackwardsName David]] [[KeithDavid Keith]].
* AllYourBaseAreBelongToUs / StormingTheCastle: In the finale, a group of heroes attempt to storm the villain's proverbial castle. However, when they arrive, they're met with [[spoiler: only Maleficent, since everyone else has gone to attack the heroes' base]].
* BookEnds: The story begins and ends with narration from Sly. Also, the first and last line of spoken dialogue are both from Deadpool, [[MotorMouth fittingly enough.]]
* [[BreakingtheFourthWall Breaking the Fourth Wall]]: The introduction, at least.
* KillEmAll: There are 84 characters. Some of them are a little... expendable.
* KirkSummation: In the final scene. [[JustifiedTrope Justified]], as it was an intentional stall for time.
* [[LoadsAndLoadsOfCharacters Loads and Loads of Characters]]: [[Characters/AdventCrossoverCrisis Twenty-five]] on the cover alone. Eighty-four in total, not counting the nameless [[MOOKs Mooks]] scattered around as well.
* MegaCrossover: But of course.
* NoHuggingNoKissing: To the point the second phrase is expressly mentioned in the summary.
* ThePowerOfFriendship: Much is made of the fact that the heroes, working together effectively, can defeat the villains, whose teamwork skills are either [[ChronicBackstabbingDisorder shall we say, tenuous]], or [[IneffectualLoner completely non-existent]].
* TakeThat: There's a running gag concerning how Sly, Ratchet and Jak last met during "[[PlaystationMoveHeroes the alien fiasco]]".
* VillainousFriendship: Quite a few develop among the villainous group. [[Disney/TheLionKing Scar]] and [[Film/TheAvengers2012 Loki's]] is especially notable.