#igniferrus

first off im the world's #1 supporter of arthur/guinevere/lancelot polyamory and also of playing with lancelot's gender, so in my version, lancelot is afab (possibly transmasc or nonbinary, I haven't fully decided) but presents as male so only a few people (arthur, guinevere, the lady of the lake (who raised him, let him dress masc and get trained as a knight, etc), maybe one or two others) know that he's not a cis man. also while arthur/guinevere/lancelot is very much a thing, they have to keep it secret, and there's still rumors that lancelot is sleeping with the queen (he is. he's also sleeping with the king. usually at the same time).

so at one point lancelot gets pregnant with arthur's child and they have problems because:

they can't exactly announce that their best knight is going on maternity leave

they want to acknowledge the baby as one of arthur's children

so the solution is to send lancelot "on a quest" where he just goes back to....the lady of the lake?? probably?? and chills with her for a while until he has baby morgan and he then secretly sends her to camelot

at the same time, guinevere fakes a pregnancy, and there's a bunch of rumors that lancelot is the father because of his conveniently timed "quest"

so when baby morgan arrives, arthur announces the baby to the court and the nobles/castle staff/etc are all clambering to see the baby to figure out if lancelot is the father. they all take one look and are like "oh. that's definitely arthur's child" (either through facial features, or im also thinking arthur and morgan have darker skin while both guinevere and lancelot have lighter skin) and some of them are a bit disappointed because they wanted to keep spreading rumors

morgan grows up in the castle and is friends with other nobles' kids, and she's jealous when the boys her age start to get knight training, so she watches the training from her window and tries to teach herself. when she's like 10, one of her friends' (still working on a name, calling her V for now) father (a knight?) dies (V's mother also died several years prior) and she's left destitute, but morgan sneaks her into the castle and hides her in her room and sneaks her food. (morgan's nanny catches on pretty quickly but doesn't say anything, she just makes sure there's always extra food left out in the room and plenty of clothes and toys)

by the time she's like 12, mordred can very clearly tell that his little sister is arthur's favorite and could pose a threat to his guaranteed succession to the throne, so he tries to kill her (poison?? maybe with the help of morgana or morgause?? or an "accident" when she's horseback riding??) and she's very sick for a few weeks. arthur strongly suspects it was mordred, but he doesn't have any evidence so he can't do anything about it.

to keep her safe, arthur decides to send her to a convent. she's upset about this and throws a fit because she doesn't realize she was poisoned, she just thinks she's being punished. she also realizes that she can't keep taking care of V if she's not living in the castle, so they hatch a Scheme™

when the knights come to escort morgan to the convent, she comes out of her room all ready to go with her hood pulled over her face and she's acting very pouty. the knights are all like "ugh why did we have to get stuck escorting the bratty princess" so they don't interact with her much, they just try to get this over with as soon as possible. they take her to the convent and introduce her to the nuns and get out of there. the nuns have never seen the princess so they don't realize that they're raising V instead of morgan

meanwhile morgan runs away, disguised as a boy, and starts training to be a knight for several years (possibly with the help of the lady of the lake)

after four years or so, arthur and guinevere send for morgan to come back to camelot to have a role in the court. when V shows up pretending to be morgan, no one knows the difference because they haven't seen her in four years and she looks close enough. V continues to live at court for several years doing princess things

eventually, lancelot and guinevere get caught, lancelot escapes, and guinevere is sentenced to be burnt at the stake. mordred knows lancelot is going to mount a rescue, so he plants a trap on the outskirts of camelot and captures him. being the dramatic Bitch™ that he is, he waits until the last minute (when they're leading guinevere to the stake) to tell arthur.

(I have this scene so clearly in my head. arthur is staring out the window at guinevere, he doesn't even turn when the big doors slam open, only looks when mordred begins speaking to him and tells him he has good news. his goons lead in a chained up knight with a bag over his head and force him onto his knees, then mordred says something like "I have captured the traitor knight" and pulls the bag off lancelot's head. lancelot and arthur lock eyes and lancelot is very clearly apologizing for failing while arthur just looks heartbroken, because not only does he have to watch guinevere burn now with no hope of her being rescued, but he'll also have to sentence the man he loves to death as well. arthur's forced to let the execution proceed and at the very last moment an army storms the square and a mysterious knight rescues guinevere and rides off with her. arthur and lancelot and relieved but also extremely confused because the knight's insignia is unfamiliar, and they have no idea what he intends to do with guinevere.)

surprise, the mysterious knight is morgan! she sends her army off to keep guinevere safe and goes to camelot under a flag of truce. she gets taken to arthur, but still wearing full armor with her visor down so no one knows who she is. she goes up to mordred and throws her glove down to challenge him to a duel to the death, claiming that he tried to kill her years ago. he doesn't deny it, saying he's tried to kill lots of people. they fight, she wins, while she has her sword to his throat she demands he withdraw the accusations against the queen and lancelot. he does, so she lets him live, but now lancelot and guinevere are free and can return to camelot.

morgan turns to arthur and pledges her loyalty and asks to be a knight of the round table, and he's so grateful that lancelot and guinevere are safe that he accepts. he asks her to stand and asks her name and to remove her helmet. she reveals that she's princess morgan, which V confirms (maybe morgan also shows a distinctive birthmark or something to further prove her identity)

yay! everyone's happy! morgan gets to be a knight and also be princess and also gets gay married to V.