"Over the centuries the Celestial Dragon's nine Dragon children have themselves had children, born of mortal men and women, who in turn, have sired their own generations. Never cross the Dragon-blooded, child, for they wield the instruments of the Empire, and -- justly or not -- may well turn them against you."
- —Liu Jianguo, Adjunct to Yuan Bo, the Jade Dragon[3]
The Dragon-blooded are the Human descendants of the Cathayan Dragons who rule over Grand Cathay and possess the ability to take on Human form and mate with their mortal subjects. The Dragon-blooded often rise to high official ranks within the state bureaucracy of the Celestial Empire and are the only mortals officially sanctioned to become magic-users within the empire.
The Far Eastern nation of Grand Cathay is mostly populated by Men, but is ruled by a family of immortal Cathayan Dragons who have mastered the art of shapeshifting into the form of their subjects. While originally the Dragon Emperor and his Moon Empress ruled Cathay alone, they eventually had nine children of their own. These Cathayan Dragon siblings, in turn, started taking Humans as mates through the ages, resulting in offspring born of Dragon and Men, who in turn went on to have children of their own. While relatively rare, the ancient nature of the Cathayan Dragon siblings means their many progeny now exist within Grand Cathay, where they are known as "Dragon-blooded."[1]
These descendants of the Cathayan Dragons often rise to positions of power in the empire, not least out of respect for their heritage, but also due to the power that comes from being a part of the imperial family. Their lineage can be a source of some jealousy and resentment from high-ranking mortals, especially when the Dragon-blooded allow their abilities to develop into arrogance.[1] The most powerful among the Dragon-blooded are known as the Shugengan, powerful spell-casters who can wield the magical lores of Yin and Yang, which are otherwise only usable by the Cathayan Dragons themselves. The Shugengan serve as the officially sanctioned wizards of Grand Cathay.[2]
Dragon-blooded who are yet to rise to their own prominence or prefer a place within the Celestial Host for the honour it brings often become Great Longma Riders. Flying to battle alongside other elements of the Celestial Host, they are the solution to endless problems on the battlefield, from eliminating enemy flyers to assaulting the hardiest of ground troops.[1] Other Dragon-blooded of low status who also develop magical abilities can often be find among the ranks of Cathay's other wizards, the sanctioned astromancers who wield the Lore of Heavens and the alchemists who wield the Lore of Metal.[2]
Many of the elite Celestial Generals who command the forces of Cathay's Celestial Host are also Dragon-blooded.[3]