Good method to complete game is play easy difficulty as Americans.
Start by getting peasants and swordsman to 10 and 4 respectively. Get some chicken farms and forester's huts to get food up so you have the units.
Then upgrade town hall and get a stable and cowshed. Now max peasants again and get 3 knights.
Now buy town hall, minotaur's maze and hydra's pond in the order of which ever is cheapest. When you purchase one also buy the max of that unit before buying the next building upgrade.
After every fight make sure to get back all your units before ending year again.
In terms of beliefs I suggest maxing the purple line (legends of the miners) then getting the turquoise line (equality church).
You get a scroll of shrinking which I recommend using year 40 against the 4 hydras if you use at all.
In terms of fighting the dens, just do them when you are confident your army can defeat them, they are a side part to the game and aren't necessary.
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