Although Duan Lingtian had previously intended to kill Yun Qingpeng, the latter's subsequent display of a "desire to survive" made him feel that keeping him alive might be more useful than killing him.
Even if the other party's hostility toward Yun Qingyan was just an act, he would only be killing one fewer lower-level Divine Venerable. The reward granted by the Rules for the death of a lower-level Divine Venerable was limited, and even if he were to harvest a supreme treasure, he was not currently in need of ordinary ones.
As long as Yun Qingpeng had even a one-percent willingness to help him kill Yun Qingyan, he would spare him. Even if the hope of Yun Qingpeng actually helping him was as slim as one in ten thousand, he would still let him go. To Duan Lingtian, the life or death of Yun Qingpeng was inconsequential.
Chapter 3942