Wu Juechen naturally listened to Li Dai above all else; whatever she said went. So when she told him not to kill, he indeed spared the realm guardian's life.
Had the realm guardian fought using other methods, he might not have been defeated so quickly. But when it came to divine souls, Li Dai and Wu Juechen were not inferior in the slightest, and were even imperceptibly stronger than this realm guardian.
From what the realm guardian had said, Li Dai could sense that he was not lying. He seemed to have misunderstood her and Wu Juechen's identities, and didn't dare to lie at all, spilling everything—what should have been said and what shouldn't, everything he knew, he said it all.
Chapter 1078