I also just used call of the wind (to summon up some throw away troops) and recieved dryads. Even with only one turn of sleep those girls locked down that Goblin shaman nicely.
Tirexes also supposedly reduce all surrounding enemies defense by 30% (the tyrant ability) but I don't know if it's working... If it does they're level 5 killers. I use them as my second tank, Royal griffons as my lambs and the Tirexes to deal with anything that decides to go for my archers, like those pesky dragons and demon lords. Slap a stone skin on them and they chew through mobs. Of course max moral really does help