Though he was only forced to take half a step back, Wu Sha’s expression gradually turned somewhat worried. In the brief exchange earlier, he had distinctly felt an extremely cold Yin presence within the other party’s Yuan Power. That thread of cold Yin had penetrated into his body, corroding it from within. If he had not already assimilated Yang Energy in his body, Wu Sha would have been caught unprepared and end up slightly disadvantaged.