For centuries dragons and humans have been in conflict with each other, until one boy and his dragon taught both races how to get along and started the dragon riders. One terrible day the riders fell and humans and dragons went their separate ways. a century passes and the dragon riders and their dragons become stories and myths to the humans and legends to the dragons. So when some explorers came a pone a mountain of dragons they wondered if the legends were true so they built a dragon stable to see if they could be tamed. They observed the dragons and started capturing the tamest and friendliest ones to train. But the humans made a big mistake by putting a force field around it so dragons couldn't escape, and many were hurt by it. It enraged the dragons and a lot of the the riders too. It wasn't until an unusual rider with her dark purple dragon broke the barrier, freeing the dragons. Some dragons went back to the wild some followed the strange rider and some stayed with their riders. Now they are left to protect the wild dragons from harm and learn what it means to be a real dragon rider.
Link to DF: Forum/viewtopic.php?f=85&t=4210964