To this end, the three great Sanctuaries began to deliberately lure Evil Gods, devising ways to kill them and then seize their controlled territories.
As a result, during this process, the three great Sanctuaries discovered... Evil Gods that controlled more territories were more powerful and more cunning.
Now the Sanctuaries were unable to deal with overly powerful Evil Gods, preventing further expansion.
So... the three great Sanctuaries began to look for allies in the Cataclysm world, established new Sanctuaries, and launched attacks on the "Boundless Heart Sea" region, in hopes of winning this apocalypse!
That's also why more and more Sanctuaries kept appearing, blooming like flowers in various regions of the world—because the closer to the center of the world, the more territories controlled by Evil Gods, the more powerful they became.
With the current strength of humanity, they simply couldn't deal with them.