In the Black Stone Domain, if the average cultivator at the peak of the Rule Integration Realm makes up the most important part of the combat strength of various races, then the peak of the Rule Integration Realm is like the sky for many smaller clans.
Of course, it's not so exaggerated for the Evil Clans, who have Open Heaven Realm elders. The death of a cultivator at the peak of the Rule Integration Realm wouldn't cause the heavens to fall and the earth to split for the Evil Clans, but it would certainly cause significant damage.
Originally, the Evil Clans had fourteen cultivators at the peak of the Rule Integration Realm with varying cultivation levels. One died in Sky Sea City, and now with Kou Fen dead, only twelve remain.
Before the incident in Sky Sea City, the human race already had more cultivators in the Emperor Realm than the Evil Clans, and even those humans who commanded more than two secondary rules in the Emperor Realm began to exceed the number in the Evil Clans.