Also, if you have magical dominance while facing an economically and militarily superior enemy dont underestimate remote spells-there are a couple of army destroyers(ghost riders and some general damage spells) and nice ways to remove commanders(mind hunt, manifestation, earth attack, infernal disease) which can greatly disrupt an enemies plans. Magical dominance should gain you the advantage in mobility and versatility and, for taking out his big armies boost your mages up to either army destroying spells(high level huge AoE/battlefield spells or massed spamming of spells such as shadow blast and falling fires) or army boosting spells; I've seen boosted militia take out over twice their number in jotuns with priestly morale boosters and alot of buffs(army of gold, will of the fates, mass mistform spell and a few castings of weapons of sharpness
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