Transmigration was a supreme law. It controlled life and death, Yin and Yang. Ordinary people could not reverse it or even touch it, otherwise they would suffer the cruelest punishment.
Of course, even Bu Fang could not revive a person from the Transmigration. It would be extremely difficult to resurrect an ordinary person who didn't have a cultivation base, not to mention Tian Cang, a top Perfected Great Saint.
The stronger a person's strength, the deeper his entanglements with the Transmigration were, and the difficulty of resurrecting him was multiplied. After all, when it comes to Transmigration, simple things become complicated.
So, all Bu Fang could do was to deceive the Transmigration.
In fact, everything was still working in accordance with the normal Laws of Transmigration, but he could exploit the loopholes in the laws so that Tian Cang's soul could stay in this world longer. That was why he used the Senseless Lotus coupled with the Time and Imprisoned Gourmet Arrays.