Fandom Specific Plot / Marvel Cinematic Universe

• You get lots of Loki redemption fics, usually forced as his punishment for the events of The Avengers — a vast majority involve Loki being forced to live with the Avengers (who mistrust and/or are hateful towards with him) in order to learn humility.
• It is almost guaranteed that unless some sort of AU/bashing is involved, all of the Avengers will be living together full-time in Stark Tower.
• There are many multiverse fics where MCU characters somehow interact with their comic or cartoon counterparts. This is especially true with Steve and Tony fics, as the duo's relationship is very prominent in a lot of different realities in different ways; for example, their decade-long angsty friendship in main comic continuity, domestic co-captaincy in Avengers Assemble, or straight-up being married in Earth-3490^* with the caveat that the Stark of this universe is a woman named Natasha. Alternative versions of them are mostly used as foils/reflections of MCU Steve x Tony's relationship.
• Loki getting pregnant is so common, fics are often labeled "Lokipreg" or "Lpreg" instead of just mpreg. He may be a contender for most knocked-up male character in fandom. It helps that Loki getting pregnant is actually canon in Norse Mythology (not that Myth!Loki ever gets pregnant as a male, though); he's the mother of Sleipnir the eight-legged horse.
• Budapest fics. If you ship Clint/Natasha, you've probably written or read something about Budapest. Any fic revolving around the members of Strike Team Delta (Clint, Natasha, and Coulson) is likely to have some references to Budapest. It's also common for Budapest to be the place where Clint initially recruited and/or encountered Natasha.
• After Captain America: The Winter Soldier, many stories have been focused on Steve trying to rehabilitate a broken Winter Soldier/Bucky, who is sometimes seen suffering from PTSD, guilt or other types of mental issues due to his brainwashing, mistreatment, and assassination orders by HYDRA. Common beats include eschewing canon compliance past CA:TWS, a first act or prologue where Bucky is in the wind and Steve has to track him down, Steve and Bucky reuniting much earlier and/or under different circumstances than they do in canon, Tony learning the truth of his parents' deaths through less-traumatic ways than how he actually finds out in canon, Steve and Bucky moving into Avengers Tower, and Tony working on Bucky's arm. Fics are generally split on whether Bucky joins the Avengers, or chooses to give up fighting for good (and potentially motivates Steve to do the same).
• Another interesting scenario that's gained some traction following the release of The Winter Soldier entails What If? scenarios where other characters are either kidnapped or raised by HYDRA and brainwashed into becoming assassins.
  • Steve is the most popular target of this, and it's almost always given a full "role reversal" treatment where Steve falls off the train and Bucky is forced to become Captain America in Steve's place only to crash the Valkyrie and get thawed out in the future. A few versions of the story will depict him as a direct analogue of the Winter Soldier, such as in the One More Troubled Soul series. However, most versions of this what-if scenario will depict Steve as "Captain HYDRA" and wearing a modified version of his costume based off of the one in Iron Man & Captain America: Heroes United (which featured a few plot points similar to those of The Winter Soldier, where Steve was brainwashed by the Red Skull). Also, whereas Bucky was an Extreme Doormat who was forced into compliance via horrific torture, Captain HYDRA more usually tends have been brainwashed via More than Mind Control and thus retains more agency and enthusiasm in his actions.
  • Peter Parker and Tony Stark are tied for a distant second place- due to Peter's age, most fics have him under HYDRA captivity from toddlerhood, possibly kidnapped in the same incident that killed either his parents or Uncle Ben; and Tony is usually a second brainwashed HYDRA Asset alongside Bucky, kidnapped and brainwashed either when the Soldier killed his parents (with or without aging him down or moving their deaths further back in the timeline) or sometimes after the events of Captain America: Civil War.
  • Sam Wilson is in an even more distant third place, with nearly all fics having him kidnapped in the same incident that killed his wingman Riley, and his wings being painfully grafted to his back like Bucky's arm.
  • Others include Peggy Carter, Matthew Murdock, Rhodey (in a role-swap fic where Tony and Steve plus most of their associates swap places, with Tony growing up in the 1940s and becoming Captain America), and even Darcy Lewis.
• Peggy Carter/Steve Rogers fix-it fics usually attempt to reunite the two in time, either by sending Peggy to the future or Steve back to the past. In the case of the former, it's usually accidental; generally, Peggy stumbles into one of Howard Stark's mysterious inventions, and it turns out to be a time travel machine that sends her to the 2010s. Upon waking up in the future, she befriends other significant characters, causes general Fish out of Temporal Water shenanigans, and, of course, has a reunion and a Big Damn Kiss with Steve. Sometimes Peggy mistakes Tony Stark for his father and he has to inform her that Howard is long dead, causing them both no small amount of angst. If Tony is a major character, he and Pepper Potts are often the Beta Couple, and Pepper is Peggy's friend. These stories often end with Peggy staying in the future; some authors simply handwave the possible fallout, and others attempt to write a plausible excuse to keep her in the modern day without changing the timeline. Rarely, Peggy is forced to return to the '40s in the end, but she usually does so with a sense of peace and closure, having gotten to say her final goodbyes.
• Stories that turn Peggy into a supersoldier like Steve are also quite common. This is often done by way of a Blood Transfusion Plot, in which Peggy is severely injured and Steve is the only person around who shares her blood type. He gives her his blood, and she gains at least some of his powers. Authors of more explicit stories sometimes invoke Deus Sex Machina instead, with the general effect remaining the same. Alternatively, Peggy is used as a test subject for some other variant of the serum, and she gets her powers that way. In most cases, Peggy getting Steve's powers leads to her being frozen with him and them waking up in the present day together. This became Hilarious in Hindsight and something akin to Ascended Fanon with the What If…? (2021) series, the very first episode of which consists of Peggy receiving the serum instead of Steve and becoming Captain Carter. And when the Watcher informs Peggy in the Season 1 finale that Steve was meant to receive the serum in the Sacred Timeline, Peggy replies that would've been quite the sight, her tone of voice making it clear that — though this Peggy fell in love with her universe's Steve for the same reasons as her main counterpart, even when he's still the scrawny kid from Brooklyn and she's now a statuesque Amazonian Beauty — she's very interested in taking a look at a post-serum Steve.
• Given that he was a popular character whose death in Avengers: Age of Ultron came off as a huge shock to the fanbase, it's pretty obvious that there's a helicarrier and a half's worth of "Quicksilver Survives" Fix Fic.
• Fics where Peter Parker visits the Avengers tower on a field trip with his school are common among the MCU Spider-Man fandom. Tony often has Peter as his son, occasionally even his blood son from his pre-Afghanistan womanizing days. Expect a Flanderization of Flash that lines up more like a dumb physical bully than the nerd rival as he is in canon.
• There are also lots of fics where May dies and Tony ends up adopting Peter.
• After Infinity War, many time travel fix-its have a member of the Avengers or other group travel back to stop Thanos.
• A number of post-Infinity War fanfic play with the idea that Peter Parker didn't die from the Snap, but was instead sent to another universe: be it another part of the Marvel multiverse or a completely different series entirely.
• There are plenty of fics using time travel to change the end of Endgame.
• If an Endgame fic isn't a fix-fic, it will focus on either Peter and Harley acting as Morgan Stark's big brothers or a Flash Forward Fic where Peter leads a new incarnation of the Avengers or even the Young Avengers (with Cassie assuming the mantle of Stature or Stinger, Harley becoming Iron Lad, Lila Barton as the new Hawkeye, and occasionally Morgan becoming Rescue).
• A post-Endgame scenario that's gained some popularity, especially among Stucky shippers, entails what's known as the "2012-verse" — the timeline where Steve steals Loki's scepter by claiming to be HYDRA, gets into a fistfight with himself, and tricks his way out of the fight by telling his 2012-self that Bucky's alive. It's been surmised that these would kick off the reveal of HYDRA early and, on a lighter note, more than likely lead to Bucky's rescue under less-traumatic circumstances.
• Many people have wondered what would have happened if the other half were snapped in Infinity War like here. Even if it's not the exact other half, many people have wondered if there was any other random combination other than the one depicted. Given the franchise has a large cast, there's over fourteen million possible scenarios.
• Post-Spider-Man: No Way Home fix-fics have gained some traction, usually involving Ned and MJ investigating who Peter Parker is, and ultimately getting their memories of Peter back and reuniting with him.

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