Cang Erzi infiltrated the opposing forces, which gave Li Yi a bit of confidence in the subsequent war. At least in times of crisis, Cang Erzi would definitely lend a hand, ensuring they wouldn't end up losing everything.
However, the matter with Wu the Taoist made Li Yi realize that he needed to tighten control over these Tri-Floral Realm cultivators. He could no longer let them act freely, even though with the Sacrifice Spell, betrayal was impossible, but he couldn't let them slack off either.
He had brought them out from the End of Dharma World, allowing them to regain life, and in return, they must serve him.
Essentially, it was a transaction.
If these cultivation experts came to Earth, regained their strength, and then refused to serve, it would violate their original agreement. Li Yi wouldn't mind grabbing one or two for public punishment as an example to others.
