A battle strength comparable to that of an immortal king

For an Immortal Emperor, achieving this was not difficult at all. 

Lu Xuan didn't resist in any way. Even with his current cultivation base, he had no chance of winning against an Immortal Emperor.

"Just now, I stopped you from killing Nangong Wuyin. Are you not going to blame me?" The Moon Empress raised her eyebrows and said indifferently.

"He was already defeated by me, to begin with. Whether I kill him or not is another matter!" Lu Xuan replied. To him, killing Nangong Wuyin would naturally cripple a great enemy in the future. But there were also reasons as to why he didn't kill him.

He no longer took Nangong Wuyin seriously after he was defeated. Just as Lu Xuan said, killing him or not killing him was another matter.

In his previous life, he could kill Nangong Wuyin under extreme conditions, let alone this life. After he surpassed Nangong Wuyin, he no longer had the chance to catch up to Lu Xuan.