Now that I think of it, it might be possible for devotion to another mortal to count just as well as devotion to a god. As such, those completely loyal to Auric would be as protected as those who were loyal to Mulcarn in the previous age, even before Auric really starts his assent into godhood. Of course, it is likely a lot easier for a god to get permission from a mortal to act on his followers than from a fellow god, and this permission likely doesn't have to given consciously or without coercion. The mortal to whom others are devoted would have to have some level of devotion to someone or something else. If the god-king's loyalty was entirely to himself, then that would actually mean his soul belongs to Mammon so the evil gods could do whatever they like to him to extort the right to do whatever they want to his followers. Theoretically a whole nation could be protected through devotion to a righteous god-king, but a righteous king would not accept being treated as a god.