User blog comment:Emptylord/Custom Champion - Dannis the Headcracker/@comment-7709681-20150501162504/@comment-1330314-20150503181501

I feel designing kits could help avoid creating Mary Sues, even from just a storytelling perspective. Working on a champion's kit means you need to give them weaknesses alongside their strengths, otherwise they wouldn't be interesting, and the same should apply to character design. Defining how your champion interacts with others (e.g. who they're strong or weak against, who they synergize with), and how your champion fits in the game in general, is also similar in many ways to defining a character's relations to others in a story. While there are definitely Mary Sue custom champions on this wiki, that's a feature that usually gets pointed out fairly quickly.