Chapitre 660: Chapter 243 Loyal Ji: Composing a Loyalty Anthem for Cultivation Path Ancestor_2

From all this, the conclusion is not hard to draw:

Supreme Unity is not cheap as cabbage; even for the Cultivation Path Ancestor, Supreme Unity is a strategic resource.

The Cultivation Path Ancestor can't casually simulate a bunch of Supreme Unity, not even one, but rather needs endless ages and massive resources to cultivate them, just like now.

This "illusion realm" he is in seems more like cultivating Supreme Unity, rather than simulating them.

Therefore, whichever Supreme Unity he chooses to replace, he can only gain less than half of their power, but he has to bear their identity and cause and effect, and participate in the Witch-Demon War under their identity.

For example, if he chooses Di Jun or Tai Yi from the Demon Race Four Emperors, facing the Twelve Ancestor Witches would spell instant death. Di Jun and Tai Yi had originally perished in the Witch-Demon War, changing to a weakened version of him would mean certain death.