Advent Crossover Crisis is one of those, if instead of chocolate, 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 and She-Hulk gave a rundown of the basic facts of the story. The first true chapter was published on the 1st of December.
It contains over 30 fandoms, depending on whether you count things like Super Smash Bros. and Disney Animated Canon as one piece of fiction, or several. Sly Cooper serves as the closest thing the story has to a "main character", while Maleficent is its Big Bad.
This fanfiction provides examples of:
- All Your Base Are Belong to Us / Storming the Castle: In the finale, a group of heroes attempt to storm the villain's proverbial castle. However, when they arrive, they're met with only Maleficent, since everyone else has gone to attack the heroes' base.
- Book-Ends: The story begins and ends with narration from Sly. Also, the first and last line of spoken dialogue are both from Deadpool, fittingly enough.
- Breaking the Fourth Wall: The introduction, at least.
- Kill 'Em All: There are 84 characters. Some of them are a little... expendable.
- Kirk Summation: In the final scene. Justified, as it was an intentional stall for time.
- Loads and Loads of Characters: Twenty-five on the cover alone. Eighty-four in total, not counting the nameless Mooks scattered around as well.
- Mega Crossover: But of course.
- No Hugging, No Kissing: To the point the second phrase is expressly mentioned in the summary.
- The Power of Friendship: Much is made of the fact that the heroes, working together effectively, can defeat the villains, whose teamwork skills are either shall we say, tenuous, or completely non-existent.
- Take That!: There's a running gag concerning how Sly, Ratchet and Jak last met during "the alien fiasco".
- Villainous Friendship: Quite a few develop among the villainous group. Scar and Loki's is especially notable.