Crush the human race, in their peak of power and momentum, in one fell swoop, leaving the human path's luck weakened and unable to recover!
Following various changes, today, the Western Wilderness has become demon territory, but within this domain, many mortals of the human race still exist.
Mortals possess strong reproductive abilities.
Some Demon Kings claim mountains as their territory, demanding tributes from mortals in exchange for protection.
Some Demon Kings establish kingdoms, where they raise mortals like livestock.
Some Demon Kings rule over the five lakes, and passing mortals must pay tributes to them.
...
In the tens of thousands of years since, there have also been Supreme Humans of the Path, but their desire to reclaim the Western Wilderness and rescue their kin has been met with heart-willing but power-lacking efforts.
To achieve this, only by ascending as one of the strongest in the absolute peak of the Human Realm can one possibly succeed.