Fei Di Lan is Fei Di Lan, the Zombie King is the Zombie King, two individuals, two concepts, you cannot mix them up.
A long time ago, when Fei Di Lan was not a demon cultivator, he was unable to break through his realm, his lifespan was running out, and he was exploring relics, looking for the opportunities left by predecessors underground.
His efforts paid off, and he found a Demon Cottage.
The unknown demonic cultivator, like Fei Di Lan, was troubled by his lifespan and unwilling to sit still, he used his own demon skill as a foundation to create a secret method for soul transfer.
The process consists of three steps.
The first step is to refine a zombie as a vessel;
The second step is to replace the zombie's heart with a magical artifact that can contain the spirit;
The third step is to place the magical artifact into the body.