Mictlan looks to be geared towards the more exprienced player and is IMO one of the most interesting nations.
The troops are primitive. Literally fighting with sticks and stones. However, they have three different holy tribal warriors that have different abilities. The eagle warrior can fly in combat, the jaguar warrior can shapechange, the sun warrior is the elite fighter (albeit not better armed than your average heavy infantry).
OTOH Mictlan has very powerful priests-mages: The High Priest of the Sun (Fire 2, Blood 3, Priest 4), Moon Priest (Astral 2, Blood 2, Priest 3), Rain Priest (Water 2, Blood 2, Priest 3), Priest King (Nature 2, Blood 2, Priest 3). Additionally two of the commanders can 'recruit' slaves (speak: more cannonfodder for your armies) for free.
Battles usually result in heavy losses, but can be replenished fast. I am sure experienced players can overcome the weak military with some nifty combos from the priests once the research has been done. And of course there will be lots of devils and demons to summon
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