If you describe something as multiform, it can exist in many forms. By its nature, a transformer toy that can double as a car and as a robot can be called multiform.
Many illnesses are multiform, like cancer, because they come in all different types with all sorts of symptoms and characteristics. But good things can be multiform as well; think of the multiform Hindu deity Vishnu with ten different avatars that range from a fish to a boar to a tortoise.