Wang Lu never really plotted for the lives of the two children. The blood sacrifice to control the Eternal Tree was actually a scheme from the very beginning.
A scheme to drive Zhan Ziye to death.
There was nothing wrong with Zhan Ziye's Eternal Tree strategy. He could indeed connect Sacred Leaf with the Eternal Tree through the spell derived from supreme wisdom. Unfortunately, Shaman went to the afterlife along with A Ye, which completely ruined his whole plan.
Without the powerful Sacred Leaf Shaman, her young heir alone was far from enough to support the spell. The only way seemed to be like what Wang Lu said, to blood sacrifice one person so that the other could accomplish it. However, previously, just as Wang Lu mentioned this plan, Zhan Ziye had furiously interrupted him.
However, in turn, what if there was no Wang Lu to tell the plan?
With Zhan Ziye's IQ, could he really not think of this method?