After the era of energy cultivation began, every ancient treant got an idea about the internal energy system, and each of them made a replica for himself that was useful to him and distributed it to his descendants and followers.
While the ordinary Treants were happy with the new cultivation system and went to wreak havoc on the human gatherings, the ancient Treants took their time to study this new field further and used the opportunity to strengthen their souls and confirm all the information they had researched over the past hundreds of thousands of years.
Soon, each of them discovered a large number of heavenly laws, and each of them created techniques and methods by which they could rule the nature around them in one way or another.