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1. They don't have flaws. Flaws are the first thing that should be explored in character, at least after the first flashes of inspiration have passed and you start moving into more concrete turf. People say Mary Sues are defined by lack of flaws; the flip side insists that giving your character "issues" won't make a character any less of a Mary Sue. Now, my definition of a Mary Sue doesn't involve flaws or the lack thereof; a Mary Sue, to me, is defined by the disproportionate amount of attention given to a Sue by the plot and the priorities of other characters. So, yes, it possible for a Mary Sue to have legit flaws and still be a Mary Sue. However, the difference between "issues" and a character flaw is what role they play in the character's deve