The idea is to deploy large forts to deny enemy maneuvering space. Tear down the facilities and build forts.
Beware your population spam. Notice how I unintentionally neglected to ensure that it stayed under 80. Send units to their doom and use gens to block as needed.
It'll be good to deploy a light machine gun unit with an inf gen.
The north's priority is are the enemy arty and the south is the heavy machine gun gen. Use all bombers on the heavy machine gunner.
Knocking out all 3 forts or the central fort triggers the arrival of reinforcements, but you'll not have time or manpower to attack it in strength. If you seal off the northern and southern passes, you may concentrate on the central fort. Ignore crossing the mountains for it is a waste of time, resources and men.
Do as I recommend, but not as I did.
Gens used: Carol I, Grant, Jackson, Straßenberg, Selivanov (the free arty gen), Ivanov and Besseler.
