The Human Pest wrote:What is the difference in M&M between "extras" and "stunts?"
Well, briefly, extras add considerable utility to a power, expanding its usefulness. Often extras allow one power to duplicate the effects of another (such as using your Magnetic Control to create a protective Force Field or magnetic Energy Blast).
Power stunts are basically super-feats with a particular power as a prerequisite. They tend to be more limited and don't expand the capabilities of a power as much, simply allow you to use it in a slightly different way. A good example of a power stunt is the Mind Control stunt that lets you give orders mentally rather than having to speak them out loud (whereas being able to read the thoughts and memories of anyone you're controlling would be an extra on Mind Control).
Extras are generally more expensive than power stunts, since extras modify the power's overall cost while stunts have a flat cost (like feats).