Because the rewards for slaying these demons are too many.
Previously, when Jack Clark participated in the Plane war, slaying thousands of demonized followers from the Abyss Demons of the Sixth-level Heaven only amounted to one Origin, converting into ten Origin Points.
Slaying one Abyss Great Demon King grants thirty Origins, which can be converted into more than 300 Origin Points.
And now, just by wiping out over four hundred Labyrinth Demons, equivalent to the Fifth Tier, from the underground dungeon maze, the rewards from this world are already comparable to one Origin.
It's tens to hundreds of times more than slaying the same demon creatures from the Supreme Abyss Plane.
That is to say, if Jack Clark slays a demon king with Mythical-level strength, he can directly receive rewards of hundreds of Origins, and slaying one with the strength of a Titan would earn at least thousands.
This reward is already comparable to slaying a True Spirit Ancient God of the Abyss Plane.
