Disclaimer: I don't own FMA. Obviously. If I did, I wouldn't be writing fictions, now, would I? More likely, I'd be in mansion relaxing in a gold bathtub filled with money. ^_^
5 Signs of a FMA Mary-Sue
Mysterious powers that just can't seem to be explained- at least not until later in the story. These are a massive giveaway, but are probably the most common mistakes authors make with their OC's. Like for example, your run-of-the-mill-Mary-Sue is expected to have the power to carry out transmutations without the aid of a circle, a logically impossible knowledge of alchemy, alchemic powers that really make no sense at all, when you think about them (being able to create shimmery shields or rainbows that glitter, or flowers out of nothing) and amazing super strength and speed, especially for someone so small* and skinny.
Clothes/styles which haven't even been thought of at this moment in the timeline.
Also, a not-so-surprisingly trademark of a classically sickening Mary-Sue. On top of which, the most popular style is scene/emo, to fit the OC's tragic, angst-y past (see number 3). Like, long glossy black hair (often streaked with red), a black hoodie/overcoat (to match Ed's, of course), a red vest, skinny jeans and black and red converse. That hasn't yet been created. And no-one blinks an eye. In fact, everyone in the story laps it up, calling her 'different', 'interesting', 'unique'. *sigh* And that was such an awesome style, too, but now it just feels tainted. :(
A dark, scarred past, that usually mirrors that of some poor, unsuspecting canon character.
A personal (un)favourite of mine. Whenever I see an OC like this, I mentally face-palm. The classic, cliché story where some innocent girl is totally screwed over, in this case, often by homunculi in some way or another, is pretty much the norm for Mary-Sues. A favourite among fanfic writers everywhere, but not so much for the readers. This past is usually created so our Mary-Sue can compete with characters like Roy or Edward, seeing as they're the ones they're usually paired up with**, and to invoke feelings of pity and sympathy in readers, so it's all the sweeter when she gets her inevitable happy-ever-after. T_T
An inexplicable knowledge of the canon characters, especially the OC's soul mate.
This one is very frustrating. Where the OC will just know about everything that's happened, how they all feel and how to make everything better. Who cares HOW she knows it, she just DOES. A very over-used way of making this possible is to have her drop in from an alternate universe via the TV show. Usually ours. The Mary-Sues in these ones are nearly always author based, because they start off in the author's position; this way, she can drop an all-new improved version of herself into the middle of her favourite anime/manga, and make all the lovable characters dance around her in (not-so) interesting and original ways. Think of it as them playing with their very own virtual doll house, where the characters are pre-made, and random people can come and praise her for her *cough* amazing ideas.
A simply amazing personality and physique, and everyone knows it but her.
Last but definitely not least. I'm running out of caffeine and will-power here so bear with me. This kind of idea usually goes hand in with number 3 (tragic past, blah, blah...) where our OC is friendly, kind, sweet, funny, kind of sassy, pretty and so much better than all of the other boring girls in the show, but seriously underappreciated, and has this MASSIVE inferiority complex, which only serves to enhance her angelic, innocent, martyr image. *gasps for breath* Anyhoo, you can pretty much always tell with this brand of Mary-Sue that they are going to eventually confront their self-depreciating ways, usually after an intervention from their lovesick boyfriend*** and finally let go of their self-esteem issues so they can enjoy their perfect life surrounded by the man of her dreams and a massive collection of doting friends.
Right. That's pretty much it, I think. Just saying right now- THIS IS FOR FUN. THIS IS NOT MEANT TO BE IN ANY WAY INSULTING OR OFFENSIVE SO PLEASE DON'T TAKE IT AS SUCH. AND IF AFTER READING THIS YOU STILL WANT TO YELL AT ME. .well, then you clearly can't take a joke, and I don't mind being yelled at, so feel free to vent. :)
*-Some Mary-Sues are small, mainly those that are inevitably going to be paired up with Edward, because since he's short, his soul mate just HAS to be short too. Because that's irresistibly cute. Apparently.
**- You'll find in most FMA OC fictions that these two are the ones most commonly singled out. 'Cause the authors think they're 'hawttt' or 'smexii'. Yeah. :( Poor Roy and Ed.
***- Usually Roy or Edward. Occasionally, Envy. No idea why though; he looks like a girl and sounds like a freaking chain-smoker.