A highly effective strategy I found for Thomas Torkve.
Located in the underground cave on Elon called 'River of Life' he's always got an army of a lot of Paladins and Inquisitors.
As far as I've seen he never casts any offensive damage magic. I always saw him cast Divine Armor on his Paladins and sometimes a Battle Cry. Knowing this is really helpful for building a good strategy against him.
If enough of his stacks are damaged in the first round he'll have most of his Paladins & Inquisitors casting resurrection magic.
Flooding him with summoned units using Druids, Royal Griffins & Demonologists worked well for me. Royal Thorns, Dryads & Demons should work well too but i haven't tried. Despite the +150% power of Paladins & Inquisitors against demon class units I didn't find this to be any trouble.
Phantoming Royal Griffins and flooding Angelic Guards works really well. Angelic Guards have 50% resistance to physical attack which the Paladins are doing and 25% to magic which the Inquisitors are doing. Royal Griffins have 50% resistance to magic so have them take out the Inquisitors. Royal Griffins on the Inquisitors will prevent them from range attacking your mages.
Even though the Paladins still take out quite a few Angelic Guards per hit they can't keep up with the flood if Mana Accelerator is used to guarantee a Royal Griffin phantom / Angelic Guard summon used every round.
Giants added to this worked well for me too. Phantoming Giants kept the Paladins quite busy and the Earthquakes were nice.
With Druids and Demonologist summons reloading every few rounds and phantom Royal Griffins summoning Angelic Guards the Inquisitors die quite early, the paladins become totally surrounded on all sides with reinforcements building up faster than they can eliminate them. Mages attacking with range on top of this. Thomas Tvorke is very easy. Granted I played him after I had gotten quite strong, I think this should work even when weaker.
