"Undead Origin"?
Wasn't it supposed to be the "Undead Energy Core"?
"What's going on?"
Gu Xi asked with a puzzled look.
"My lord, I just asked. The 'Undead Energy Core' was originally a fragment of 'Undead Origin.'
And 'Undead Origin' was the first textbook for necromancers.
Because it had taught too many necromancers and carried the hopes of countless necromancers, it had a chance to advance to Red Quality.
But it was destroyed during the advancement attempt, leaving nothing behind.
Even its details were erased from the world.
Only the book itself still remembered what it was.
However, according to the 'Undead Energy Core,' to restore it to Orange Quality, we need to gather a total of twenty-one books, including 'Undead Scourge Thought Analysis,' 'Underworld and Netherworld,' and so on.
Only by recombining them would there be a chance of doing so.
If we use the skill of 'Three Hundred Children's Songs' now, we'll be skipping that step.
We'll directly obtain the legendary 'Undead Origin.'"
"Wait, wasn't this book copied by Eve? If it can be found in the library, gathering twenty-one books shouldn't be difficult, right?" Gu Xi interrupted Yan Ruyu.
"It's very difficult, because no one knows about the book 'Undead Origin,' much less its combination formula.
Moreover, some of the books used in the combination have undergone years of revisions, and even their titles have changed.
Without enough luck, it's impossible to find all of them."
Yan Ruyu explained further to Gu Xi.
Only then did Gu Xi understand the reasoning behind it. He asked another question.
"Which is stronger, 'Undead Origin' or the 'Undead Encyclopedia'?"
"Put it this way: the 'Undead Encyclopedia' was developed and expanded from books such as 'Undead City and Necromancer,' 'Undead and Undying,' 'Toxic Undead,' and so on."
At that point, Gu