While Dong Tianyu was working hard outside, his family had also managed to settle down in the Refuge Center.
Looking at the survival points that no matter how they absorbed or decomposed wouldn't decrease, Dong Tianyu knew that he hadn't found some necessary upgrade elements. He guessed that these upgrades might need some mysterious items which couldn't be obtained in the outside world, so they had to be compensated by using survival points.
Fortunately, after the reduction, it only required 500 survival points. By absorbing four points a day, until now, enough survival points have accumulated for the upgrade.
With Dong Tianyu choosing to upgrade the Refuge Center level, an invisible wave, like throwing a stone into a pond, spread from the center to the outer edge of the cave mansion, after the collision with the edge, it rebounded back to the center.
