The Rules of Engagement
There are many planes of existence, and each plane has its own gods. These gods are powerful beyond comprehension, and wise enough to know that if they ever were to come into direct conflict with one another this power could destroy all of creation. It was thus agreed upon by the divine of all worlds that any combat between worlds would be fought by their creations. In order to give a world its proper chance to defend, each world may assemble a force for its own defense. This force is known as The Chosen. The rules regulating the formation and use of The Chosen are frequently known as "The Rules of Engagement" or "The Rules of the Game".
 The Rules
 The Union of the Chosen
In order to give one world the chance to peacefully interact with another, the Chosen native to a world will not be united by fate in defense of their world unless an interloper makes a direct act of violence against the people of the world. The exploitation of this rule is at the core of almost all D'Karon attacks. They enter a world and peacefully find their way to positions of power. They then advise the leaders, manipulating them, but always taking direct action only when ordered to do so.
 The Number of the Chosen
To prevent the gods of a world from assembling an army of handpicked and handcrafted warriors, the size and risk of a world permit it to have a maximum number of Chosen. In the case of the setting of the Book of Deacon series, five Chosen may be assembled at any one time, and the Chosen may be assembled only twice. The D'Karon often seek to exploit this rule by sparing the lives of a world's Chosen until The Great Convergence has occurred, then killing them, thus preventing any additional Chosen from being selected. If they succeed, and are able to kill or corrupt any remaining creatures who are worthy to be Chosen, then a world can be entirely stripped of its defenders forever.