in chapter 20, Ren Woxing and Linghu Chong were competing sword stances. Ren Woxing let out a mighty roar which knocked out Linghu Chong unconscious. Is this because Linghu didn't have much internal energy (did Ren Woxing realize this?)? Who else would have been knocked out by this loud roar? Would it have worked on people with comparable internal energy?
Seems like a nice, unexpected trick in duels.