[PvK]

If flaming counts as magical, then it would also handle the pesky ethereal units.

I think high Astral 4 is tempting with Iron Faith too, to get a blessing to magical resistance.

My first Iron Faith game uses a Prince of Death with Death/Blood/Fire/Earth all at 4, and air and water at 2. This gives four bless effects to my Templars, and gives me good searching and forging/casting possiblities. Blood was kind of silly, until I moved into the Mictlani capital...

My sentimental favorite is still a dragon. I think the main point though is to get the magic you want to have on the pretender, especially in the regular flavor Ulm, since they have no random spheres in their national units. For Iron Faith, consider bless effects, and realize there is a basic random sphere pick unit available.

PvK