Legacy of Shantiri

How to beat it. I managed to complete the first part, but I can't figure out this one. At the beginning, I got a "Rassay" creature, and I upgraded "Darkness" so that "Rassay" could give bonuses to everyone. Then, Orcs came, and they removed the bonuses with a "Tent" and easily defeated me. Also, I don't understand how to level up a Mage in the Orc town. The Orcs have zero stat increases, and before this, I managed to rebuild 3 creature dwellings, but I couldn't find where to upgrade them. In general, I'm lost. Maybe you can suggest what I'm doing wrong?