The relationship between the fake Celestial Master Zuo was interdependent with Fairy Queen Li. The fake Celestial Master Zuo was perverse and had done all sorts of outrageous things. He had tried many ways to annihilate the followers of the real Celestial Master Zuo and promoted his own followers.
Secondly, he should have practiced some evil power which required human's resentment as the base. He had been quite successful at his practice and had now reached a spiritual power of at least level ten.
Thirdly, Mu Feng and the other three messengers were probably still alive and were currently being controlled by something or someone. However, they had been turned into puppets for the fake Celestial Master Zuo and would do whatever he ordered. Their behaviors were no different from usual, so Li Mengxia and the rest did not suspect them at the beginning and handed their jade tablets over to them. They almost obeyed their command to kill people.