In the Doomsday World, Zheng Yi carefully studied the human bodies here and finally came to a conclusion.
That is, the people of the Doomsday World are innately lacking Spirit Roots, meaning they cannot cultivate using the Cultivation Methods of the Great Yi City Immortal Realm.
However, their bodies do possess their own unique attributes and evolutionary traits, where through powerful external stimulation, such as consuming Zombie Crystal Cores, they might gain inexplicable strong superpowers, becoming Superpower Users.
Although Zheng Yi hasn't studied what kind of cultivation system Ghost Masters follow, it is very likely similar to Superpower Users, but their evolutionary paths have diverged.
This could be attributed to the differential rules and energy levels of the world.
Even though Zheng Yi has consumed numerous Zombie Crystal Cores, there isn't a slightest sign of awakening any superpowers.
