Elder Tiegu was very concerned about the Speculator that was seized back and added over a dozen seals to it.
Initially, he merely decided to join forces with the Wanhuan Sect people to abduct Feng Jun, not caring much about the Speculator.
However, Feng Jun escaped, and they heavily injured Wan Qing, making this battle quite a loss, as setting up formations costs Spirit Stones.
Still, none of that is important; silencing witnesses is the real deal. True Immortal Jiu Cai and his Nascent Soul Initial Stage disciple knew each other and didn't guard against each other's bloodthirsty instincts, resulting in their complete obliteration.
To put it bluntly, True Immortal Jiu Cai was also too self-confident, losing due to his arrogance. He should have been on good terms with the Lingmu Sect during his development in the Yi Yun continent, but aside from planning normal growth, he entertained ideas of killing and stealing treasures, so he aligned himself with Lingmu Sect instead.
