The Demon Tomb is a sealed location beneath the world.
It is a vast underground world that spans the entire planet, once a part of the Land of Calamity, filled with countless Demons, impossible to fully exterminate.
There are even a large number of Divine-level Demons.
A hundred years ago, human Awakeners made a huge sacrifice to protect the populace of the entire planet, sealing the underground world where the Demon Tomb is located and closing off the barrier between it and the Land of Calamity.
Since it is a seal, there must be entrances to the seal.
There are two entrances to the Demon Tomb, one located at the Heavenly Ghost Pass in the Beiyin Domain, and the other beneath the ground of Jiuzhou Imperial City.
Because the Demon Tomb was sealed, humanity, long oppressed and ravaged by Demons, blew the horn of counterattack, driving the remaining Demons into retreat.
