The 15 Core stats are are broken up into three groups. Prime stats are the most critical as they enbody the base line for all of the other abilities you have. Each Prime has within it a body and a trait. These further define a creature to show it's true streangths or weaknesses.

The first prime is Power, it encumpasses strength, and might. Power's body is Brawn which provides potency to your attacks and force to your grappling. Brawn also provides the ability to carry more and work at a forge effectively. Power's trait is Fatigue, Fatigue allows one to go above and beyond their normal limits or to grapple and hold breathe longer.