C31 The Law of Gravity

Ling Tian took the letter that his grandfather left in his heart, analyzing each and every sentence, coupled with the knowledge from his two lifetimes... As time passed, he slowly formed his own experiences. This seemed easy, but it was difficult to do. It took him twenty days to do it. Right now, Ling Tian was combining his experience with actual practice. Thus, the changes now should be done