IN part 6 of ROTRL Kazaven wields the Staff of Hungry Shadows and it says he uses it to call a devourer to his aid. This is indeed an ability the staff possesses but it seems that it is immediately loyal to him and gets no save against it. Is this flavor? Possibly an understood agreement between the two (as it is a named devourer). If it isn't just for flavor, the staff calls forth the same devourer each time and he is loyal to the staff's owner, should this extend to the pc who gets the staff?