[PvK]

As usual, hit them as soon (during a battle) as possible, and develop something that doesn't get banished, as soon as possible.

Large numbers of skeletal horse in the front and front flanks are pretty dangerous since they are so fast and have good attacks, even if they die quickly.

Use the national unholy protection spells, since they will help at least a bit - against a large number of attacks, so the total effect is worthwhile.

PvK