When you're in a setting that has fantastically empowered people, be it with magic, robotic suits, psychic powers or just the good old fashioned Superman Default Selection of Superpowers, it can be tempting to have the characters just bulldoze through everything in their path. Solving any problem in a matter of moments, with no bad guy too tough or situation too large for them to deal with. Heck, this was considered to be one of the possible inspirations for Superman, creating a character that Siegel and Schuster could use to solve the problems that they weren't equipped to deal with as teenagers in 1930s America, be they slumlords, gangsters, war profiteers, mad scientists etc. etc.
But really, where is the line that you draw between getting your character be an awesome and extrahuman person who can be used well in stories, or them becoming that most dreaded and overused of terms that now haunts all discussion of fiction today: A Mary Sue.
