In the second week, I spent time capturing the pink compass for a double resource bonus.
In the third week, there was a blockade of 100+ Medusas in the center of the road, guarding Pandora and the Hive; Pandora gave me all level 4 creatures. Solmyr was without earth magic (I made a mistake with his build, as I decided to take ranged attack early on, but it didn't pay off). I had Labeta with earth magic and erudition, and I retrained her in all magic skills.
In the fourth week, after I drove the opponent's forces out of the center, he summoned Craig, with combat stats twice as high, slightly higher magic stats, an army of 14 Archons, few ducks, and native creatures. The key moment was Labeta attacking him with a small number of creatures to trigger his spell, he split the stacks of Archons into two stacks of 7, and I was able to take 4 Archons. At the moment when I had 2 units left, his two stacks couldn't reach me in one turn to attack, but both were affected by the spell. In the front battle, he had enough creatures so that I couldn't move in the second round.