For every 10 units in your army, hire: 3 Templar Knights. 1 Sergeant at Arms. 4 Archers / Crossbowmen / Mix. 2 Siege Machines. For instance, if you have an army consisting of 100 units, the most optimal composition would be: 30 Templar Knights, 10 Sergeant at Arms, 40 Ranged units and 20 siege units.