Astrid Freeman (dragon rider)
History of Dragon Riders:
Dragon riders are different than most supernatural creatures. They have heightened strength and speed, but that's about it. Inside of them lives their dragon, which normally comes more visible during early teenage years (around the time of puberty, can take longer if they aren't exposed to their people and their abilities). When a dragon rider releases a roar, the dragon itself is able to "come out" and do their duty to protect their rider. Riders also have the ability to grow talons and fangs when fighting on their own. Eyes glow a vibrant orange when angry, usually threatening to release the dragon.
Dragon riders have a hatred against Vikings when they were still around (some believe they still are, despite no seeing them). Vikings kill dragon riders to protect people from the riders that don't have control over their dragons. In those rare occasions, the dragon takes over as the main host and the rider ultimately disappears.
A dragon can "free" their dragon, but this can be only be for a short period. When a dragon as been separated from their rider for too long, they will do whatever they must to find their rider. This can range from minimal damage to cities and towns, to burning them down and killing people. All so they can find their rider.