Mutants & Masterminds is a superhero role-playing game published by Green Ronin Publishing. There are three distinct editions. First edition was based heavily on the OGL SRD, but included many novel elements, including its flexible power points system. Second edition heavily overhauled the game, particularly how powers were packaged and bought, but retained a distinct d20 linage. The third edition was a major departure. Although similar in many important respects, it changed the basic attributes, changed how attributes scaled in keeping with a DC Heroes inspired exponential system, and embraced a simpler, more intuitive approach to game mechanics.