After all, cultivation was a long process. Three years was equivalent to the snap of a finger for cultivators.
In the past three years, the cultivators' realms have not improved much. After all, even Su Yun, who was a Dao Ancestor, needed a few years to cultivate in seclusion, let alone others. Hence, if they wanted to survive this crisis, Great Xia could only rely on technology.
The mecha research and development department was iterating the Door God series of mechas day and night because three years later, when the alien civilization arrived, the Nantianmen Plan would become the first line of defense on Earth.
The weapons development department was constantly perfecting the existing weapons systems such as the Xuanwu Fighter, the Luan Fighter, and so on to ensure that everyone could unleash their top combat strength at that time and do their best to have the advantage in this inevitable crisis.