After defeating saxons near castle Colle, you have moved to mountains Minaros, where the evil kings live and where the leader of saxon armies has made agreement with kings to attack you.
They also build fortresses and have constructed gatehouses too.
1. Build walls around your castle as fast as possible
2. Produce buildings and army quickly. as you will get attacked frequently
3. against demons use spearman and produce a lot of archers.
4. Save your game after each accomplishment.
5. for capturing 2 stone circles you will be free from invasions, and for killing all dragon nests you will get rewards.
6. After all its all intuitive.