[Taqwus]

Top-level SG unholies get to reanimate Apparitions, IIRC, at the added cost of population. The Apparitions are ghostly fellers with a disease-causing aura.

Hm, regarding theme confusion... it bothers me that for provinces of enemy dominion, even if you're occupying them or have a spy there it won't tell you the theme, or even which is the worshipped pretender. Sometimes this is fairly odd, e.g. you'd think that Miasma would be self-evident, as would Carrion Woods, and that the dead Ermor themes would also be readily clear (although not necessarily distinguishable).