"This is the martial art Old Empty cultivated," Lin Feng's gaze flickered. It seemed that Old Empty had refined the first move, "Slaying Shadow," and combined it with his unique shadow Wuhen, making it truly powerful.,Lin Feng went through the other martial arts on the bookshelf, but could not find one that was more suitable for him than the Cross Shadow Killing Technique. Eventually, he gathered all the martial arts on the bookshelf and placed them inside the stone ring.,Lin Feng subtly shook his head. Old Northern didn't mention this huge door to him, and it was clear that Old Northern as well as the predecessors from Cloud Sea Sect never opened this door before.。