Every physical part or object in the region was the same. They acted akin to viruses, ones that looked no different from a regular part of the land. Though at the very moment they came into contact with Godly Energy, they become sentient, absorbing the Godly Energy as they grew in size.
Then, they would turn into monstrosities that attacked any and every source of Godly Energy. In this case, the sources were the cultivators. After all, there was not even an ounce of Godly Energy in the region. It was completely devoid of it.
Therefore, any hint of Godly Energy would seem like the sun in the middle of the night. Therefore, if Krune wished to remain alive, he couldn't use any Godly Energy.
Even the barest minimum of action would emit some Godly Energy. A regular cultivator wouldn't even realize it. After all, there was usually a considerable concentration of Godly Energy in the God Realm, at least equivalent to a Rank One God Stone in quality.