Hey all. New to the forums.
I play against my brother mostly, who rocks the Priestess while I play Warlock. We haven't been playing too long, so grain of salt and all that, but I have noticed that the Priestess can't simply summon cleric after cleric early on successfully with the temple, or theyll just get slaughtered. A better idea is definitely what Pixel hinted at, which is setting up some defensive units early on, and maybe a wall too.
A Knight of Westlock and the Priestess with her staff and/or Deflection Bracers guarding the zone is pretty potent and relatively efficient...both have a good defense that protects against range attacks, and both punish attacks within their zone heavily; the Knight with his defense and 5 dice counterstrike and the Priestess with her ability to Daze a unit into its NEXT action phase (I believe that's how it works if a unit gets dazed AFTER activating), and swing back for 4 dice.
This goes doubly if the Knight is still on guard for the next action phase...he can effectively put TEN dice on a unit that is dumb enough to attack in his zone. Pretty much means I have to take him down at range and hope for crits, since his armor is pretty high, or feed him an imp so my bloodreaper Dark Pact Slayer can do some real damage to him. There's other ways to deal with it, like Knockdown or Force Push-ing him out of the zone, but that's one less attack or spell I have towards killing the valuable targets in the zone, so he's already achieved his goal...and then still swings for a ton.
Yet another reason why I like the Fire school in combination with demons. All fire spells except Fireball are unavoidable, so defenses won't help, and demon's fire immunity/resistance helps keep the pressure up in a particular zone without the need to retreat them. Still a tough fight, but very balanced.