Your character is an Archon (or, if you want, a human, but that poses its own set of challenges).
An Archon is an entity of greater physical and magical strength than humanity. The greatest of them are regarded as divine; others are seen as spirits, angels, demigods, and the like.
Each Archon possesses three (or in the case of the Praetors, four) spheres of influence from which their powers are decided. These include Fire, Magic, Death, Earth, and stuff like that.
Additionally, each Archon belongs to a Faction. They can ally themselves with the Andrilim, Malthidrim, Deltharim, or Nevithim depending on their philosophies and personalities. Choose the one that's the best fit for you.
Everything is explained in greater detail in the group's Journals. Also, there is an introductory flash animation in the gallery for your viewing (just ignore the apprentice system, that was scrapped).