You suddenly notice little critters scurrying around the Valley. Many are sitting on the backs on various Dragons. Even more are flying through the air or chasing one another on the ground. A herd of horse-like things are grazing in the corner alone. Confused by their seemingly random existence, you point at them.
"Those are Companions. These little critters keep the Dragons company and guard them. Some have special powers. Five have been discovered so far." SPO replies. "They follow the same rules as Dragons and can't leave the valley. They were drawn by InvaderWater and Black Angel."
Companions are small, dog-sized creatures that collow the Dragons around. When a Companion links with a Dragon, they are inseparable. Companions grant Dragons special powers, like passing on markings or mutations they did not formerly have. Many Companions have no effect. Magical abilities relate in no way to species, but more to personality.