Well, I'd imagine we would have to transfer our characters roles' stats into actual combat. Such as in Onyx's case, he's fast and agile, yet isn't going to be able to hold his own for long on frontal combat. I believe it would just be a compilation of common sense, and reasoning... And badassary, of course. Can not leave out badassary.
Also, gonna go look for Onyx's themesong, just a little tidbit to add on.