After Yang Guowei returned to his clan, he did not reveal the truth about leaving for the upper dimension. He was unsure about his future, so he did not want to give his clan any false hope. So, he only told them about the mini-Heaven Will Battle and that he would do a secret task for the Heavenly Emperor.
Afterward, he prepared for the battle. During the previous one, he did not even have an opportunity to perform and show the world what he was capable of. He also hopes to change people's opinion of him after associating with these traitors for so long.
Someone had a similar reaction to Yang Guowei–Jingwu Hua. After returning to her clan, she did not say much about the deal. After the issue with the Emperor Bone, she had never truly trusted these people.
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