This is the story of a crazy lich who possesses an internal game system and brings catastrophe to the entire world. “Let’s look at the daily quests today… it’s the damned choose one-of-two-options-type again. Destroy a town with a population of 30,000 people or above; reward: 10,000 evil points. Steal lollipops from 3 children; reward: 1 evil point. If neither of the quests is completed, then 2 points will be deducted.” “Tsk! You think I’m stupid? If I really destroyed a town, a crusade of Myth-ranked Holy Knights would definitely come hunting me down. Even if I earned the points, there wouldn’t be any life left in me to spend them. I better just go be a kindly lollipop bandit.” I’ve already had enough of being a notorious lich. Who says a lich can’t be a good person? I’m definitely going to beat this damned system and be an upright and dignified good man.
The beginning of the demon wave was a historical event, as well as a critically important event in the Holy War's timeline.
The demon wave's arrival signified that the Chaos Abyss had successfully connected to the mortal plane. It would be very difficult for any Chaos Abyss resident to come to the mortal plane when it wasn't a time of Holy War, and the Chaos Abyss resident would also be quite weakened and easily kicked out of the mortal plane. But now, not only was establishing portals easier, even powerful demons would no longer be restricted by dimensional laws in the mortal plane now.
However, there would always be demerits together with benefits. Previously, due to dimensional laws' restrictions which forcefully suppressed those from the Chaos Abyss, the Demon Lords were only able to send out incarnations, clones, descendants, and so on. Even if they suffered some losses in the mortal plane, it wouldn't mean their actual death.