He was able to associate this with the strategy of retreating to advance, and used the Weaving Technique to "pollute" the Divine Array, thereby tainting Beibei's Sword Will.
Look at this!
Beibei struck down the Four Great Fierce Beasts with a single sword strike but fell into the trap himself.
The Fourth Sword's Heavenly Unravel Imagery was far from "dead." Instead, it hid within that strand of the "ultimate" demonic aura, infiltrating the very essence of the Supreme Emperor Sword.
After Heavenly Unravel, the Supreme Emperor Sword emphasized regaining a physical entity, imprisoning and slaying with the greatsword.
After the Heavenly Unravel of the Fourth Sword, priority was given to the void form, while also accommodating beast form attacks.
As the saying goes, you can't have your cake and eat it too. This latter method sacrifices a great deal of straightforward offensive attributes.
But at the same time, it added a smidge of trickery to its capabilities.