How Long Does It Take You to Create a Fictional Character?
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Minor characters come quickly, usually, as they may have only a few distinguishable features. You usually don’t need to develop them too much, though you can certainly make them memorable. Major characters are different, because they must be complex, with depth and substance. You don’t want them to disappear when they turn sideways. The bad guys must be in some ways sympathetic, the good guys must be flawed.