Shape-shifters were beings who could change their forms to however they liked: a human, an animal or they could imposter someone. They relied on magic, because when magic vanished all shape-shifters were stuck in whatever forms they currently were in. It was common for shifters to forget their original form, having changed so many times. The only known shape-shifter is Lysandra. Erawan's Bloodhound might have originally been a shape-shifter.