It turned out that the sky had two different types of cultivators. Heaven and Earth differentiated among existences that they could throw away and others that they had to keep at all costs.
Noah and King Elbas initially found it hard to believe that revelation. They didn't care that the sky sent lightning bolts. It made no sense for Heaven and Earth to have a privileged group of cultivators when they owned those laws.
However, the explanation for that feature turned out to be simpler than they expected. Heaven and Earth weren't omniscient, and they couldn't instantly understand everything about laws. Some existences could escape their immense knowledge.
Noah and King Elbas had seen that many times already. The members of their group were perfect examples of experts that Heaven and Earth couldn't understand. The rulers wanted to absorb them for that very reason, and they were even willing to reserve special treatment for some of them.