User blog comment:PurpleCheeseDragons12/When does a character become a Mary Sue?/@comment-15225862-20140122023057

Usually if a character is completely over powered, has no weaknesses and is liked by every other character, is usually when a character can be considered a "Mary-Sue". Often times these Mary-Sues are based off the creator themselves, or is like the creator except without all the flaws. Often they will also be shipped with a canon character, or even multiple. And they might have really dumb, unrealistic names. Basically, a "perfect" character. No one can be perfect, making it unrealistic.