The Mirror Knight had killed him one today and if the anchor hadn’t made sure that his soul stayed in Creation, that it didn’t disperse, then the Severance’s cut would have been the end of him. Return wasn’t an absolute, because no matter how powerful a story there was always a weakness. And I’d learned his, I realized, entirely by accident. Years ago, in a fight that had nothing to do with him at all.

...

The Dead King, then had removed his soul when he became undead through the ritual that destroyed Sephirah when he effectively died.

So if his death was undone, it’d come back.

...

Hanno of Arward’s hand touch the Dead King’s forehead, that rough workman’s palm covering it.

“Undo,” the White Knight said.

And as Creation screamed, life roared back into the Dead King’s corpse. Millennia of weight fought the White Knight’s fresh aspect, an oak tree to a dandelion, but a finger had already been laid on the balance. I had Sentenced Neshamah to die, and for that he must first live. So colour flushed back into his cheeks, those pale brown eyes widening as his magic rose again.

- Book 7, Chapter 67: And Justice For All (Redux)