Mage, The Storytelling Game of Modern Magic
"Don't let the other guy Immanentize the Eschaton."
In Mage, you are one of the Awakened, a person who can alter reality with but a thought, and probably a wave of your wand/sword/ohmmeter. You are a member of one of the Traditions dedicated to gaining Ascension, either for yourself, your Tradition, or even all of Humanity. Yes, you can throw fireballs and lightning bolts as the Mages of Legend have done, but the forces of Paradox keep you from doing it often, if at all. Paradox is what keeps reality in line with what the Sleepers believe it is, and most Sleepers do not possess an active belief in Magick. So you must often disguise your Magick in ways that can be explained away, thus Static or Coincidental Magick, which rarely attracts Paradox. Another reason for this is the Technocracy.
The Technocracy and its Conventions have, over the last several centuries, enforced the dogmatic scientific viewpoint upon reality, thus causing the Paradigm to shift from the Mythic Age of Medieval times to the Scientific Age that exists now. They fear that which comes from the Umbra and wish to block the Spirit Plane from the physical world. Their form of Ascension brings everyone to an equal level, whether it be mediocre or otherwise. The Technocracy has also enforced a Pogrom against the Traditions to prevent interference from them.
There are also the chaotic Marauders who desire a return to the Mythic Age, without regard to the consequences. And the Nephandi, who wish to achieve Ascension via Infernal means. Along with the Conventions, these groups are the Traditions' greatest foes.