The Lord of the Universe's sudden arrival and the things he said had truly shocked and unnerved Chi Xue and the others. They were especially rattled when they heard he had already subdued Ling Tian. But Divine Emperor was clever, and he quickly calmed down and realized the Lord of the Universe was lying. He came to that conclusion because he trusted Ling Tian's strength and wits. They had great confidence in Ling Tian's earlier analysis, and even greater confidence in his strength. At the very least, they didn't believe the Lord of the Universe could subdue Ling Tian without anyone noticing—especially since the two clones Ling Tian had left behind were still perfectly safe.
From these clues, Chi Xue and the others quickly figured out the Lord of the Universe was lying. They then concluded that the Lord of the Universe was currently unable to do anything to them. If he could capture or kill them, he would have acted already instead of being so long-winded. After all, in their experience, the Lord of the Universe usually attacked without warning rather than threatening them with words. Besides, they believed Ling Tian had already taken all the Saint-grade Heavenly Treasures with him to meet the Lord of the Universe, so they had no need to go meet him themselves.
From all this, Chi Xue and the others judged that the Lord of the Universe's power was limited. At the very least, at this distance he had no confidence he could take them down. Once they realized that, they breathed a little easier. If the Lord of the Universe wasn't absurdly powerful, then they had some chance of defeating him. At the very least, they and Ling Tian could still work together from within and without and possibly beat him.
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