If the alien species attacks the planet Divine Ancient Continent, then because Ni Yang's true form is present here, it might be possible to spend a great amount of Essence to fight with it, or even to kill it.
However, Guleng Star is not Divine Ancient Continent; Ni Yang isn't here. Once that Level 7 Calamity Monster appears, the only fate awaiting everyone is destruction.
Given this hidden danger, Zhang Xiaoman couldn't just leave without any preparation. You must know that this time marking the fourth star pattern is not just about three years. Besides the time needed for imprinting the star pattern, he also needs to factor in the time for nourishing it. Even with Ni Yang's Divine Skills speeding things up, it would take more than four years.
Therefore, to ensure the safety of Guleng Star, he and Su Changqing among others devised a plan: relocating the survivors of Guleng Star.
