Excellent campaign! It was quite easy until I reached the 4th mission. I can't seem to win the final battle.
Added after 15 hours 0 minutes
I completed the 4th mission, but I'm having trouble with the 5th. I defeated one guardian, and I tried various unit combinations, but the only way I could do it was by losing all my mummies. I took out the Cyclops with Divine Might.
I completed the campaign! I really enjoyed the campaign; the gameplay and story elements are excellent. Usually, if something didn't work out, it was only because of my inattention. I managed to kill the key guardians in 2-4 attempts, and Elrath on the first try. Divine Might, 5 times for 4k damage – and that's it.