Shen Hao had once asked the Analysis Department of the Global United Front to calculate how many undead would be needed to destroy current human civilization.
If based on the lowest Level, Level 7, a number exceeding 1.3 billion would put human civilization at risk of extinction.
Of course, that was the result from ten days ago.
Human civilization had experienced unprecedented rapid development in these short ten days. Not to mention, the completion of five thousand Underground Cities alone brought significant power. Moreover, the addition of several powerful species and the support of the Sky Spirit Civilization as an ally meant that their strength changed every day.
However, no matter how much they grew, when the number of undead reached three billion, four billion, or even over ten billion.
Human civilization would still face a fatal threat.
What's worse, this scenario was possible.
