The giant flame lizard, the Elder Salamander Prince Zenon, was a spirit on the same level as Sinea, evidenced by his level and his naming convention. As spirits, they were the peak of their respective elements and were incredibly rare.
[Since spirits don't naturally grow on their own, contractors are indispensable. These factors... stimuli, experiences, will, all have an effect on a spirit's growth.]
"Then what about you, Sinea?"
[Me? Well... you and I are pretty much already contracted, Paul Zero.]
Lee Shin Woo asked, and for some reason, Sinea blushed and seemed embarrassed. That was enough for him to figure out what was going on. When he gave her the spirit stone in the past, she awakened as a Dryad Princess and a contract of sorts was formed between them.
[...It seems like you have met a good contractor. How enviable.]
Zenon breathed out a tiny bit of flame, and gazed at Sinea. It didn't seem like he was being sarcastic; it looked like he was genuinely jealous of Sinea.
The reason was easily explainable. Sinea just said it. A contractor was essential for a spirit to reach level 7. Zenon must've had a contractor in the past as well. Of course, it didn't really matter at this point.
Lee Shin Woo gazed at the injured flame lizard, and spoke his mind.
"You're name is Zenon, right? I'd like you to tell me about the Spirits' Spring, as well as how you got here. ...How you lost your contractor, and what happened to the other spirits. Could you tell me?"
[You said you came from the Underground Empire? If that's the case, then you should already have a grasp on the situation; do you really need to hear it from me? Are you trying to make me suffer?]
"You see, I wanted proof. I've been looking for proof ever since I came up to the surface."
That's right. The purpose of his dual identities, Lawrence and Kay, was to find proof of what had happened. He'd never thought of himself as hero material and he certainly didn't intend to meet God's expectations, but... he felt like it was his obligation to figure out what had happened to divide the underground and the surface.
In order to appease the souls of the countless undead he'd slain thus far, as well as the other heroes who have fought on the same battlefield with him, albeit briefly.
[Is that so... Fine. I ran away that day; perhaps this is the reason I survived. Follow me. I'll guide you.]
The salamander turned his body. Lee Shin Woo, Jin, and Sinea glanced at each other and followed him. However, the inside of the cave didn't match his original expectations of the Spirits' Spring.
It was known as the paradise of spirits, or the origin of spirits... a bright place filled to the brim with magic, and a place overflowing with the aroma of spirits. A place that all spirits yearned for as if it were their hometown... That's what he'd thought it was, at least.
"...A shelter?"
"Hey."
[Indeed.]
Jin blurted out and Lee Shin Woo quickly retorted. However, Zenon looked nonchalant and nodded his head.
[Of course, it wasn't like this in the beginning. It was formed from the collective will of the spirits and was a resting place for all spirits. A place that welcomed all spirits, which was akin to a spirit's hometown. However, that was all in the past. Ever since 'that day', it's become a shelter for all the escaped spirits. ...Perhaps it would be more accurate to call it a place of exile.]
There were several spirits that dwelled within the Spirits' Spring aside from Zenon. All of the said spirits were wounded, with wounds big or small, but their mental scars were worse than their physical ones. Although their minds should be sound, their eyes were lifeless, and merely leaned upon the trees, the spring, or the walls.
What's the point of a beautiful interior when its inhabitants were exhausted? Wherever he looked, the scattered spirits looked as though they were dead, and he didn't really know what to think. Sinea was currently looking for any Dryads that might be inside.
"You can't heal your wounds... No, you've chosen not to heal them."
[Spirits are living beings composed entirely of mana and a soul. If we lack in either, then we don't heal.]
"...How sad."
But aside from the inhabitants, the Spirits' Spring did indeed meet his expectations. He could feel the overflowing spiritual power (of various elements) everywhere and enjoyed the mysterious, natural objects that were formed from rock, water, and flames.
There were several objects akin to Sinea's spirit stone rolling around. But they were, of course, much smaller than the one he'd given her at the time.
'And the spirits... They're, on average, level 4. About 20% of them are level 5. There're about 10,000 of them total. While it may seem like a lot, this is a place where all the spirits on the surface (where they're abundant) gather, so it's actually really low. Which means that several of them died or were chased off to the Underground Empire.'
He saw a few level 6 spirits as well, but nothing more. Moreover, the higher leveled spirits seemed more mentally scarred, as the higher their level, the clearer their mind was. Sinea looked as though she would cry since she could empathize with them more, being a spirit herself.
[Paul Zero.]
"Yeah, I'm right here."
[You can't leave my side.]
"Yeah, okay."
Sinea clung to him even tighter. He looked around the Spirits' Spring; the mood had become as depressing as a graveyard. Zenon called for Lee Shin Woo, who was astounded by the size of the Spirits' Spring.
[Now, let's talk.]
"Are you done testing me now?"
[I don't follow human conventions. I just didn't know how to deal with someone as powerful as you. A spirit follows you around, despite not being formally contracted to you, and you can even assume a spirit's form.]
As expected, Zenon was extremely straight forward, perhaps because he was spirit. Considering how frank he was, Lee Shin Woo realized how impossible it would be for him to imitate a human being.
[You first wanted to know about the Spirits' Spring, right?]
"Yeah."
Lee Shin Woo followed Zenon and sat down. Sinea clung to his back, and Jin bent his legs and sat down as well. Zenon breathed out some flames into the air and began his story.
[Apparently, the Spirits' Spring was created partly as a joke. There are times when a spirit wishes to relax and be free of its contractor, so all the spirits worked together and created a small world that the humans couldn't enter. It was also used as a shelter for spirits that didn't have a contractor and were thus in danger, or those who had lost their contractor.]
However, the Spirits' Spring was meant to be a resting place. The spirits created the Spirits' Spring through the common human perception of the spirit world and was set up so that spirits could easily find it, while outsiders couldn't.
Moreover, the Spirits' Spring was kept a secret, even from the spirits' contractors. That's how this 'secret garden' was formed.
[That's why. The reason why this many spirits were able to survive on that day...]
Elementalists were those chosen by spirits. One could become a magician through training, but being an Elementalist depended on luck and talent, so it was a highly coveted position.
The Magic Empire, which was ruled under logic and reason, didn't welcome their existence. No, it was closer to say that they 'hated' the spirits. Those emotions were like a ticking time bomb, and when those explosive feelings burst...
[They waited patiently for their chance. The day we were banished, they declared war on us (spirits and contractors), and voided our rights. They wanted to completely erase the spirits' existence on the surface.]
"Keuk."
At that moment, the Spirits' Spring momentarily seethed. The temperature of the ground had instantaneously increased by at least 10 degrees.
All the spirits raised their lifeless eyes and stared at Lee Shin Woo. Although he hadn't gotten any more details, he could feel the images of that day rushing through his head. They were probably memories of all the spirits living in the Spirits' Spring.
'A normal person would probably faint from these memories.'
That day, the spirits and Elementalists had lost their lives to both magic and the sword. There were those who had been banished underground, as well as those who attempted to escape the surface. There were spirits who lost their contractors and retreated to the Spirits' Spring, as well as spirits who attempted to escape underground while protecting their contractors.
The events of that day occurred hundreds of years ago, yet the surviving spirits remembered it clearly, as though it were just yesterday. This was their eternal punishment for surviving while their contractors had not.
"...Then tell me more about the day of your banishment."
[There were two princes with power (magic) that could rival the Emperor. The Crown Prince was weaker than the two, but with the help of the Royal Magician Leader, who hated Elementalists, and the Imperial Army, he managed to banish them underground.]
Originally, the Magic Empire had created giant facilities underground and left the monsters that were difficult to handle down there. However, the Crown Prince wanted to trap the 2 Princes and their forces there as well, as they were a threat to his power.
This included the Demi-Humans (who weren't accepted by the Empire), the criminals from various species, the monsters that posed a danger to the Empire, and the spirits and Elementalists. In exchange for all of them gathering together and leaving, they would be allowed to live.
It was a success. They resisted fiercely but were eventually chased underground... and were unable to leave.
"...Tell me more about how they were trapped."
[It's a type of prohibition magic. 100 light magicians and 100 dark magicians were gathered, and by sacrificing both their souls and their magic, they created a chaos element magic barrier. A barrier that separated the surface and the underground.]
"A chaos element barrier."
He finally knew what happened. His (non-existent) heart pounded in his chest. Yeah. He already knew about the barrier.
The Underground Empire hadn't fallen due to the presence of the undead. Rather, the barrier had already existed when they were banished underground!
[It's as you think. It's a barrier that doesn't allow any living beings from escaping.]
"...Huh?"
It was Jin, not Lee Shin Woo who asked. Jin's goblin fire looked slightly forlorn.
"It stops all living beings from escaping... Not the other way around?"
"He just told us. The two princes' forces were banished underground before the undead curse even existed."
"Then... Huh?"
"Yeah."
Did he finally figure it out? Jin's goblin fire curled up. Lee Shin Woo marveled at how well he could express himself with his goblin fire alone and was now sure... and said what was on his mind.
"The Emperor wasn't seeking immortality. ...He just wanted to get through the barrier and return to the surface."
Jissehanu, the Undead Emperor, hadn't failed.
He had succeeded.
That's how they had all become undead.