A grotto-heaven was a pocket world that existed independently within the larger world.

Not only could mortals survive within a grotto-heaven, high-tier grotto-heavens boasted unique environments that allowed mortals to cultivate certain types of cultivation methods quicker or develop specific abilities.

The earliest grotto-heavens were all naturally occurring pocket worlds. Human Immortal Lords speculated that many natural grotto-heavens were formed from the remains of ancient gods and demons after their deaths.

In this world, the history of non-human races far predated that of the human race. The Northern Liao alone had a recorded history spanning three million years, while the Shamans were even older. It was said that the oldest races could be traced back tens of millions of years.

During the Distant Antiquity Era, the powerful beings of these non-human races revered the concept of returning to heaven and earth. Upon their deaths, their bodies would slowly disintegrate and become part of heaven and earth once more.

However, some ancient warriors were so powerful that upon their deaths, their bodies warped the environment around them...