Tang Zhen was directing the construction of the rebirth altar in an empty Valley.
When he heard that someone was going to auction the foundation stone of the tower in the auction house, and it was a top-grade foundation stone that could produce a protective shield, he immediately put down the work at hand and drove to the commercial area.
Although the Holy Dragon City had the weapons from the original world to defend the city and had astonishing destructive power, it still had a lot of disadvantages.
If the flying monsters were fast enough, they could definitely charge into the Holy Dragon Valley with ease.
The last time the four-legged flying dragons attacked the city, they had successfully charged into the Holy Dragon Valley.
Back then, if they had a defensive barrier with no blind spots, those four-legged flying dragons would not have been able to charge in even if they died of exhaustion.