The Uncertain Trumpet, by bliumchik. Het, Scott/Jean. (ca. 525 words)
This is just a short comment fic, but with the cool premise that the material for Scott's glasses hadn't been developed, and yet he still manages as a member of the X-Men in the field (through his connection to Jean) while truly blind.
Forgotten, by Cyndrarae. Slash, Scott/Logan. (ca. 2,500 words)
In this AU Scott survives X3 but has amnesia, and Logan eventually finds him. Also it is hookerfic, so you get two fannish tropes in one, which in this case is definitely a good thing, since they go great together with Scott angst.
Jus Ad Bellum, by Jenn. Het, mainly Logan/Rogue. (ca. 156,800 words)
This novel is recced all over the place, and rightly so. It's brilliant. There are two timelines, the one we know from the movie, and one where Rogue died on the Statue of Liberty, and Rogue discovers how much one event can change everything when she's thrust into the other timeline. But it is more than that, confronted with the realities of that universe, her perception and reasoning start to shift, and it is absolutely chilling to experience alongside with her how easy it is to slide into justifications, to adapt and accept. This story deals with morality, with terrorism, war and torture, and the choices everybody has to make each day. I only stopped reading briefly, because I had to sleep for a few hours, and even then the story followed me into my dreams. It's movieverse, but takes elements from the comics and adapts those too.
An Unusual Situation, by Jenn. Het, Logan/Rogue, Scott/Jean. WIP
This hasn't been updated since 2001, so it might well stay unfinished, however I didn't regret reading the first four parts. The premise is that the X-Men don't find Logan and Rogue after Sabretooth's attack, and the story is set five years into that future. I thought it was very interesting how Logan and Rogue in this reality turned out. The story unfolds gradually along two timelines, one five years in the past, one now, and though it's incomplete I like what's there.
Freefall, by Penknife. Gen, references to Scott/Jean and Xavier/Magneto. (ca. 20,800 words)
It's a rewrite of X2, what if Scott and the Professor hadn't been captured, but escaped with Magneto instead? (needs an AO3 account, though it is still available unlocked on IJ)
Powerswap Challenge responses.
Minisinoo's Powerswap Challenge resulted in many interesting AUs, in particular I liked Broken Home (on ff.net), by Alara Rogers, Down the Rabbit Hole, by Mara, Opposites Attract (on AO3), by Penknife, Drawing in a Mirror by C. Elisa, and Secret Weapons (on AO3), by Andraste.
never too late to be who you might have been, by acetamide. Slash, Charles/Erik. (ca. 19,600 words)
This is a fix-it via time travel, i.e. Charles and Erik from shortly before Cuba are transported into the future to the time X2, see how things turn out between them and then do better.
your head caught in a waking dream, by addandsubstract. Slash, Charles/Erik. (ca. 23,100 words)
The scenario here is that Charles' parents had him committed to a mental hospital, which did not help much with his telepathy. Eventually Raven (whom he met like in canon) manages to break him out with Erik's help, and they hunt for Shaw.This is great h/c and I enjoyed how much damage was done to Charles and how he's slowly healing, while hunting for Shaw with Erik and Raven and killing people with his brain. (also on AO3)
An absence which could not be more there, by aesc. Slash, Charles/Erik. (ca. 18,000 words)
This is a modern day AU, still with powers, and has quite lovely worldbuilding detail. I liked the exploration of dating with telepaths, and thought it was quite neat how the story contrasted the intrusion of telepathy with the way Erik can also glean information with his powers.
Extended Jam 'verse, by aesc. Slash, Charles/Erik. (ca. 27,000 words so far, the second story is still a WIP)
In this AU series mutants are publicly known, and thus in the late 1960s our characters find themselves in the middle of the mutant rights movement as part of the broader social movements, rather than in the middle of superhero/villain fights.
Peregrine, by Aeshna. Slash, Charles/Erik. (ca. 6,500 words)
This is wingfic, with a winged Erik. This has lovely detail, and I liked that Erik still has his regular powers too.
These Bridges We've Built, by alishatorn. Slash and het, Charles/Erik, Azazel/Mystique. (ca. 22,700 words)
Mystique leaves Kurt with Charles, so some contact between X-Men and Brotherhood is started. I liked how the ensemble came together and the way Charles and Erik reconciled against adversity. It also has good fanart.
Try, Try Again by and_backagain. Slash, Charles/Erik. (ca. 5,680 words)
A Groundhog Day AU, in which Erik eventually manages to fix the outcome.
Remedial Dragon Training 030, by Anon. WIP
I don't know the How to Train Your Dragon movie with which this is a fusion, but Dragon!Erik is quite awesome.
Omega, by apokteino. Slash, Charles/Erik. (ca. 44,660 words)
In this AU mutants are public but segregated on Genosha, and human born mutants are sent there based on gene tests. Charles' parents hid him. I really enjoyed the worldbuilding in this AU.
Faults for Fixing, by beren. Slash, Charles/Erik. (ca. 25,500 words)
In this Charles makes contact with a mutant with precognition via Cerebro and sees the possible canon future, and prevents it from coming true.
The Shadow of the Moon Won't Do, by brilligspoons. Slash, Charles/Erik. (ca. 1,200 words)
This is a straightforward alternative to the beach scene, but a lovely example of this genre.
Hellfire AU, by Cesare and helens78. Slash, Charles/Erik. (ca. 54,700 words so far in three finished stories, but the series is still a WIP)
This is a modern day period dystopia in which mutants are enslaved, but Charles and his group are part of a mutant resistance.
lay down beside me (so still and so soft) by C_Gracewood. Slash, Charles/Erik. (ca. 53,500 words)
This is a really enjoyable fix-it. It retells the XMFC movie, but with Charles and Erik developing a relationship, accompanying angst, and a happier ending.
Empowerment, by Coriander Tea. Het, Erik Lehnsherr/OFC. WIP (ca. 111,000 words so far)
This is kind of a Mary Sue story, in which the OFC time travels and thus enables a fix-it scenario, but it is a lot of fun to read. So I don't mean it in a negative way. It's a good action-adventure, and I liked the OFC. Unfortunately it's not been updated recently.
A Man of Light Virtue, by cygnaut. Slash, Charles/Erik. (ca. 13,500 words)
Charles with telepathy working as prostitute tends to challenge my suspension of disbelief for AU scenarios, but I could at least see this story's premise getting Charles there (more or less a mix of sugar daddy and telepathic scam, that gives Charles good money without stealing, and perhaps was a path of least resistance kind of thing). I liked the atmosphere, and the relationship. Also that it was not a reformation/rescue kind of scenario.
Strict Machine, by euphorbic. Slash, Charles/Erik. (ca. 150,600 words)
This is a biker gang AU, without powers. Usually I'm not that fond of no-powers AUs, but this one is very vivid, so it really pulled me in, and I'm enjoying it.
Night Fishing at the Seine, by furius. Slash, Charles/Erik. WIP
Charles and Erik meet in Paris before the events of XMFC. I'm enjoying the atmosphere of this, and so far am intrigued by the plot.
Not Half As Blinding, by keire_ke. Slash, Charles/Erik. (ca. 29,500 words)
In this AU Charles dies a comic book death from which he gets better eventually. But meanwhile Erik doesn't leave the others.
Beloved of ravens, by khaleesian. Slash, Charles/Erik. (ca. 19,100 words, now with a sequel of about 42,800 words so far)
This is a vivid Viking!AU, which I particularly like because they still have their powers.
Big Fish Little Fish, by lilacsigil. Gen. (ca. 5,600 words)
In this AU Erik's comic-verse human daughter Anya is alive, and we see how events of the movie change (and what turns still out the same).
Puzzle Pieces, by lilacsigil. Gen. (ca. 15,000 words)
Here Darwin's death was of the comic book death variety, and Magneto & Co. realize that he can be put together again. Things go wrong and it's up to Mystique to organize a rescue, and to cooperate with Charles.
Three Kinds of Learning, by luchia. Slash, Charles/Erik. (ca. 16,500 words)
This is a nice mix of adventure with some humor. Erik tries to recruit Charles to his Brotherhood, after Raven introduced them, and then they are pulled into an adventure as Raven goes missing.
Any Measure of Peace, by manic_intent. Slash, Charles/Erik. (ca. 19,400 words)
The beach scene at the end goes differently in that the Americans and Soviets do not try to blow up the mutants. I enjoyed how it introduced Fury and Weapon X here as government factions into the plot, and how Charles injury happened later on.
Skin Deep by manic_intent. Slash, Charles/Erik. (ca. 29,400 words)
A werewolf AU. It startled me a bit that Charles shifts into a female wolf despite being a male human, but it worked quite well, and I liked the worldbuilding.
Tessellation, by nekosmuse. Slash, Charles/Erik. (ca. 116,700 words)
In this AU both Erik and Charles are mutant rights activists. Erik is based in Genosha, and more militant than Charles, but he sort of has a crush on Charles whose writings inspired him. They meet at an event and things between them proceed from there, along with a good action-adventure plot.
No Yesterdays On the Road, by pocky_slash. Slash, Charles/Erik, Moira. (ca. 42,275 words)
This is a fix-it story in that its premise is that Erik stayed after Cuba to help build the school, but the bulk of the reconcilliation in the story is between Erik and Moira, who have to team up to find Charles after he suddenly vanishes.
MCIS: First Case, by Pookaseraph. Gen. (ca. 25,000 words)
This a modern AU, a fusion with NCIS I suppose, which I don't know, but I read it as just an government mutant agents AU. Erik is an agent, Moira his boss, and she partners Charles with him. The author says it's the first in a series that will be Charles/Erik, but this first is gen.
Mutually Beneficial Transaction, by Pookaseraph. Slash, Charles/Erik. (ca. 41,500 words)
This is a no powers, modern AU, but quite an enjoyable romance trope story. Erik and Charles meet through a sugar daddy website, because Erik wants to finance college debt and Charles wants something easy and convenient. Of course they fall in love, yet are both clueless.
Taken By His Majesty, by Pookaseraph. Slash, Charles/Erik. (ca. 27,500 words)
Erik is a Roman legionnaire taken captive in Britain by the Celtic leader, Charles.
A Boy and his Bear, by PoorMedea. Slash, Charles/Erik. (ca. 4,450 words)
This is a fusion with A Bear Named Winnie. So there is fluff with a cute bear cub, and a fix-it via bear power.
The Weight of Water, by pprfaith. Het and slash, Charles/Raven, Charles/Raven/Erik. (ca. 51,000 words)
This isn't too far from canon in the setup, except that Charles forms telepathic bonds, and the consequences of that are really well explored here, not just as romance ploy, but also the scary implications, both of Charles being powerful and subtle effects which accumulate and change all three of them.
Phoenix Street, by Quietbang. WIP (ca. 6,900 words so far)
This is a modern AU, but still with powers. Mutants are public, Erik is a cop and Charles a college student, there is a murder mystery. I'm enjoying the worldbuilding here quite a bit. Unfortunately it's not been updated recently.
Limited Release, by rageprufrock. Slash, Charles/Erik, Hank/Alex. (ca. 58,000 words)
This is a loose fusion with White Collar in which Erik is a mutant in the FBI and Alex is a mutant criminal, released to help him hunt for Shaw. It doesn't try to match up with the White Collar scenario completely, but has good worldbuilding and fun plot.
Searchlight, by Red. Slash, Charles/Erik. (ca. 2,100 words)
This was absolutely creepy and terrifying, yet awesome. It's an AU in which mutants are dehumanized and kept in research settings and the report-format of the story was ideally suited for this, and I liked the ambiguities that came with it, even though I normally dislike that in fic. Also check out the sequel Methods of Deduction by tawabids in the same thread, which is good as well. (originally on the kinkmeme)
Engine of Creation series, by Regann. Slash, Charles/Erik. WIP (ca. 77,000 words so far in currently two completed stories)
This is a space travel AU that mixes XMFC with elements from Andromeda, plus some alpha-omega dynamics. I'm really enjoying the action-adventure and team here, and Moira as ship AI is great. (Unfortunately the series isn't on AO3 anymore, but both completed stories are still journal posted.)
Imaginary Life Journey, by renata_kedavra. Gen, with implied Erik/Raven, Charles/Erik. (ca. 9,000 words)
Two scenarios in which Erik and Raven, and Erik and Charles respectively, try to recruit Kurt Wagner. This just has a lovely atmosphere (and the bits in French and German actually add to that and work), and is a good character study contrasting Kurt and Erik.
In London, by rrhiab. Slash, Charles/Erik. WIP (ca. 29,000 words so far)
This is a Victorian AU, with powers, and so far I'm enjoying the setup quite a lot. It has Charles doing charity work, partly as cover to find more mutants, and Erik as a dock worker who tries to find his mother's killer.
Mr. Xavier's Neighborhood, by SharpestScalpel. Slash, Charles/Erik. WIP
This is a series of snippets is adorable. Erik is raising Pietro and Wanda and has a crush on Mr. Xavier who hosts a mutant-tolerance children's show.
New Beautiful Things Come, by singlecrow. Slash, Charles/Erik. (ca. 17,600 words)
This is a modern AU with mutants being public in which Erik has a kosher bakery. It wasn't a setup I expected to get into, but the atmosphere and worldbuilding works, and it's a happy making story.
Humane Society, by smilebackwards. Slash, Charles/Erik. (ca. 10,000 words)
A delightful kitten!AU, now finished and reposted from the kink meme. The author sums it up as "Basically, mutant supremacist Erik gets transfigured into a kitten, human Charles takes him in, and Erik really can't help falling in love." I couldn't describe it better. (also on AO3)
Center of Balance, by soundslikej. Gen. (ca. 1,600 words)
This is a five things story with the theme "five mutants Charles Xavier never met at age 12, and one he did" and the snippets are a great mix from sweet to creepy. (also on AO3)
Synthesis (Scenes from an AU), by starlady. Slash, Charles/Erik. (ca. 15,200 words)
The author claims this is not a fix-it for the ending, but it definitely is a reality where Charles and Erik are not on opposite sides in the future, and Erik stays rather than leaving, without any radical premise shifts (like the AUs below). So that counts as fixed in my book.
Start a War, by stewardess. Slash, Charles/Erik. (ca. 34,000 words)
In this AU Erik is a cyborg.
Show Me Your Teeth, by tawabids. Slash and het, Charles/Erik, Charles/Moira, Raven. (ca. 26,500 words)
Another werewolf AU. In this one Erik is a werewolf, Charles a werewolf hunter and they team up against Shaw. Also, don't miss the short epilogue that is in a different thread.
A Degree of Hope, by TigerDragon. Het and femslash, Charles/female!Erik, Raven/female!Erik. (ca. 77,000 words)
This is a female!Erik AU but has AU worldbuilding that goes beyond this, so I enjoyed it a lot, even though I'm not particularly fond of genderswitch AUs. The switch here tied into the worldbuilding of a somewhat more mundane introduction of mutants to the public than an international nuclear missiles crisis. I enjoyed the take on how a day-to-day mutant culture might develop in the parallels with queer history with clubs and clinics and such.
Possible Worlds, by trailingoff. Slash, Charles/Erik. (ca. 12,000 words)
This is a fix-it via a mutant-ex-machina do-over, or rather it takes even more than one try, and I like that they have to work to make things right. (also on AO3)
Linger by waldorph. Slash, Charles/Erik. (ca. 29,700 words)
This is also a modern AU with mutants being public, in which Erik hears Charles in the apartment he rents, like a ghost haunting it. I liked the ensemble plot in this.
A Family Portrait In Progress, by Xris. Slash, Charles/Erik. (ca. 47,700 words)
This is not so much a direct fix-it as a later reconciliation, in which Charles ended up raising Lorna initially without knowing she's Erik's daughter. It's a series with two finished stories so far.
Dead Man's Paradise, by Yahtzee. Slash, Charles/Erik. (ca. 24,000 words)
The setup is inspired by some anime series I don't know. Basically mutants who are imprisoned are used in gladiator fights for entertainment purposes, and one of those places is run by Shaw. Erik ended up there because he killed a Nazi, Charles got himself imprisoned looking for Raven. I liked that it started rather dark, but then ended more hopeful. I also liked that the dehumanizing setup twists people (sort of a Stanford prison experiment) but that Charles showing solidarity changes things for the better, so it's not completely bleak for all the dystopia.
Enigma, by Yahtzee. Slash, Charles/Erik. (ca. 11,100 words)
Erik goes back in time, but the turning point here is not Cuba but he goes back to before his mother died, becomes a WWII mutant hero, "Enigma", and changes his life as well as history of human-mutant relations.
Father Charles series, by Yahtzee. Slash, Charles/Erik. (ca. 75,000 words)
This one has Charles as a Catholic priest, and also the interesting twist that their mutant powers seem to exist in some way, but they are less aware of them.
In Shadow and Silence, by Yahtzee. (ca. 13,000 words)
This AU setup is basically a vehicle for extreme h/c, but really enjoyable for that. Mutants are oppressed and experimented on. Charles, who survived experimentation by his family and was rendered mute, runs a mutant sanctuary, and rescues Erik who has been blinded by experimentation.
Paralyzer, by Yahtzee. Slash, Charles/Erik. (ca. 43,500 words)
Another with Erik as a cop, but set in the 1960s, and this one has a cool twist to the cop premise, in that a big part of Erik's motivation to join the NYPD is strategic infiltration to prepare for the human-mutant war he expects, so he can network with mutants, gain access to weapons and information and such. Charles is an FBI agent here, and they hunt a truly creepy mutant serial killer together.
Undone, by Yahtzee. Slash, Charles/Erik. (ca. 6,600 words)
Another time travel scenario. Here Charles consciousness from post-X3 goes back to his younger self just after Shaw's attack on the CIA.
Time to Grow, by zarah5. Slash, Charles/Erik. (ca. 21,000 words)
This is another fix-it for the ending of the XMFC movie, in that Erik sends Azazel back to evacuate Charles to a hospital which leads to a better outcome of the injury and eventually also gives more opportunity for reconciliation between Charles and Erik. And I really enjoyed the latter aspect of the fix-it, and how they mend ideological fences, but I'm somewhat ambiguous that it also erased Charles disability at the same time.
Dæmon 'verse, by zihna. Slash, Charles/Erik. (ca. 41,000 words; the series is a WIP, the individual stories are complete)
X-Men: First Class with dæmons, what's not to like?