(Is this topic bumped? I'm gonna post anyway!)

I probably do. Unless you're really good at balancing things out, there's bound to be at least one little stinker crawling around in there that you might not even notice. I don’t have any super powered characters, so it can be harder for me to spot at times. If I do have a Mary Sue, it's mostly the minor characters since they don't get as much character development. If (and there probably is) it's a main character, It's because I don't really put as much thought into them as much as I do with one of my favorite main characters. Normally Mary Sues come around when a person likes the character too much, but I like to give my favorite characters noticeable flaws. I don’t know if this is normal, I have an obsession with giving my characters mental illnesses or neurological disorders, so it makes it easier to base the flaws around that. Plus, some of mine are built up to seem like Mary sues, but as time goes on their flaws become more obvious. For example, Artie, one of my favorite main characters, is built up to be sorta the nice guy who’s a little sensitive and annoying, but he’s hard to hate and later in the story he becomes even more of Mary-sue material due to some talents that aren’t presented right away. However, eventually went he gets the thing he wants most and it spirals out of his control, he noticeably becomes a weak, self-pitying person and turns out to be neglectful of the people who depend on him, causing them to developed negativities as well. I suppose it might be smarter to introduce that earlier before he puts people off, which is what I’m working on now.

I think Mary sues can be prevented as long as you put your ego aside and realize that the defects are what make the character who they are. Even when you “self-insert” (which is irritating in itself) you have to realize you have flaws as well. The whole wish fulfillment stuff is entirely the wrong road to go down, even though we all do it. I think it’s also important to give your character ACTUAL flaws. A lot of people use the excuse of “they’re clumsy” or “They say stupid stuff!” but those don’t work because they’re endearing flaws that make them cute and funny or some shit. Half the time the whole clumsy/stupid side is hardly reflected on or disappears as soon as said characters gets serious anyway. Actual flaws, like arrogance or cowardice, are realistic and help the good qualities in the character to shine through. Also, physical faults are great as well. Even if your character does have their share of personality flaws, if they’re young, beautiful, and stunning they’re still hard to relate to. Age, weight, ugly blemishes (cool scars don’t count!) or just general unattractiveness makes the character more human. I’m guilty of having on-and-off physical flaws; sometimes the other characters will point out their unattractive qualities, but then suddenly they’ll be handsome or beautiful in the eyes of the same people. If I have an attractive character, I try to make their personality flaws more evident.

I've been accused of including Nikita in my comic as a Mary Sue, but I think that was more because, at the time, she was the only female character in the comic. I guess this person assumed that she must be an author-proxy.

She definitely has flaws, though, and her flaws are totally different to mine. She's jealous, has a violent temper, is quite sarcastic and can be cold/unemotional towards other people. That's sort of the opposite of me. :)

Rosalyn is an interesting character... if I took a Mary Sue test with her in mind, she'd probably score 100%. Flaming red hair, skimpy outfit, large breasts on a slim frame, sexy and sassy, good fighter, men are attracted to her, women jealous of her, etc. Thing is, to the CHARACTERS, she would essentially be a Mary Sue-type, but from the readers' perspective, it's clear she's an awful person who probably should have been marooned months back. Sort of a subversion, I guess. :)

I'm trying not to have a Mary Sue in Negligence, although Lizzep can be borderline at times. I'm trying to make it so that all my characters have flaws, yet most of them are still likable. Although, I do have a character named Marilyn Susan Ojmiz that mocks the Mary Sue archetype.

I did some Mary-sue tests I found on internet to almost all my characters and no ones are mary-sues! I don't like them, they're boring and generally the story is classic, stereotyped.
I prefer my characters simple, and possibly with no powers. (( doesn't mean I don't enjoy characters with supernatural powers! )