In May, around midsummer, the days became progressively drier.
The armies of Yin Country set out from Xiqi, heading straight towards the Five Passes.
The Five Passes, from west to east, were Sishui Pass, Boundary Marker Pass, Cloud Piercing Pass, Tong Pass, and Lintong Pass, which controlled the traffic between Xiqi and the Wang Ji region. Together with Dragon Severing Ridge and Azure Dragon Pass, which lay between Xiqi and Nan City, Yin Country controlled the lifelines of Xiqi's connections with the outside world.
Once these critical passes were locked down, Yin Country could completely seal off Xiqi, thereby suffocating the enemy's economy, politics, military, and all other major arteries.
War is a matter of comprehensive national power. By merely remaining stationary, Yin Country could starve Xiqi to death.
