Many creatures are different from the mortal men who roam through the realm.
Some of these creatures are not regarded to be living while they're not
considered to be dead either. Some creatures such as imps and hellhounds for
example are considered to be demonic and originating from other worldly
planes. All these creatures share specific weaknesses that the forces of good
have learned to take advantage of. Very similar is the case with angels. These
powerful and divine creatures make formidable adversaries but some diligent
priests have found that they do have their vulnerabilities. They do not
normally belong to the world of men and thus they can be expelled by the might
of Draen-Dalar.