healing is very good in beginning of game
when u have low numbers it's easy to heal a tank
furthermore light of life can be very good if troops are camped and the undea will run away
it can do alot of damage when u have order at 3 and the skill there after(which increase healing res and such)
like 1k damage on 3-4 stacks+healing your own
book of evil is a great spell
cast it next too his casters
and enemy stacks try to kill it
same goes for phoenix