Things were indeed as the World-Ending Thunder Dragon had said. The reason Chi Xue and the others hadn't extremely compressed their Small Worlds wasn't that they couldn't do it, but that there was no need to take such a risk. Especially outside the universe, even if they faced the Lord of the Universe and used self-detonation, they couldn't pose much of a threat to him. What was more, constantly maintaining their Small Worlds in an extremely compressed state would require them to divert a considerable part of their attention. That would prevent them from fighting the Lord of the Universe with all their strength, and would instead weaken their combat prowess.
Hua Min'er and the others were different, though. They might not take part in the battle against the Lord of the Universe, so they didn't need to worry that splitting their focus to control their extremely compressed Small Worlds would weaken them. More importantly, they were inside the Lord of the Universe's universe. If they self-detonated, they would certainly cause him considerable trouble, especially after he had fought Ling Tian in a fierce battle and was sure to be greatly weakened. Using this method then would naturally pose an even greater threat to him.
Ling Tian had thought of this too, but he didn't make a decision right away. It wasn't that he thought Hua Min'er and the others couldn't master this secret art. More than anything, he was worried that if they saw him fall, their emotions would become unstable and they would choose to self-detonate, which would only put them in danger.
"Heh, you don't need to worry that your friends and family won't be able to master the extremely compressed Small World. After all, their Small Worlds are much smaller than Chi Xue and the others',