Howl, Swarms, Mind Duel, Seeking Arrow, Manifestation, scattered chaff, Storm, Darkness, Heat from Hell, stealthy units with Bane Venom Charms, Miasma, etc. It depends.
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Are we insane yet? Are we insane yet? Aiiieeeeee...
How about some 20-odd disintegrating spectators and 300+ undead fodder? Place the cavalry rearmost and the rest to attack up front. The spectators can manage nearly 100 troops in the first 5 rounds, then they start summoning more fodder and casting whatever the AI feels like they should (which, thankfully, includes some more disintegration).
Ermor can easily manage that by turn 25-ish with a decent gem income.
Suddenly occurs to me to ask, do spectators/dusk elders and so on get two attacks/turn with power of the sepulchre?
Which also leads to me ask, does power of the spheres increase unholy level too (as does communion)? If so, suddenly empowered arch bishops sound like a great idea....
How about a handful of leaders with Bows of War ordered to fire at enemy archers, spaced out so most of your bolts will miss them, possibly with anti-missile cloaks. And whatever infantry & cannon fodder, and a few small arrow fodder teams to attract AI archer attention.
With only 5 cheap men with Bows of War (perhaps scouts, or cheap commanders), they with fire 130 arrows in the time your 95 crossbowmen will fire 95. Many more of our shots will land on your Groups of crossbowmen and hit someone, than your bolts will hit our single archers standing in the open, and 80% less if we use anti-missile cloaks.