The light-bodied brezak is a species of large lizard with skin flaps that, when extended, allow the beast to glide on the air currents surrounding the mesas of Zygerria. Domesticated brezaks are used by the royal Zygerrian guards to patrol the ground for escaped slaves. The beast's skin flaps are anchored to a flexible rib cage that allow the brezak to spread them wide. Its flat tail serves as a rudder, giving the animal -- and a capable rider -- a remarkable degree of control in the air.