A couple of months passed, and the Big Brain Slug shared a couple more secrets.
The short excursion had paid off quite well.
The Zephyx production of the city forces had increased by around 5% just because of the Big Brain Slug itself, and with its additional secrets, the city earned even more.
By now, reaching the new goal for Aegis' tribute was no longer difficult, and the city had a lot of leftover capital to reinvest.
The number of Extractors also steadily kept increasing since the smaller Manufacturers needed more people to search for Specters.
About 10% of all the people living in the city were Extractors, which came to about 1,200 Extractors.
There were about 400 Newbies, 500 Johns, 200 Veterans, 70 Experts, and 30 Specialists.
Additionally, the number of Specters Crimson City contained kept increasing with time.
Crimson City was gaining far more Specters than it was losing.
Aegis' tribute adapted to the power and number of Specters contained in a city.
Naturally, as the city gained more Specters, it also had to pay a higher tribute.
The reason why the Big Brain Slug increased the city's income by that much was that 90% of the Zephyx it produced went directly to Aegis.
The more Specters the city itself owned, the easier it was to pay the tribute.
After all, Manufacturers only gave between 30% to 40% of their Zephyx to Aegis, while the city gave 90%.
In the last couple of months, Nick hadn't left the city.
Originally, he wanted to investigate the cave system some more, but with the Big Brain Slug, he didn't need to do that.
He just needed to wait for the Big Brain Slug to talk about the cave system some more.
And eventually, it did.
After handing over a couple of Hatchlings and Adolescents, the Big Brain Slug was willing to talk about important secrets.
Nick went to the Big Brain Slug and listened to its secrets, and when he came out again, he knew that capturing it had benefited humanity greatly.
A quick argument with Aria later, Nick traveled to the cave system.
Naturally, Aria wanted to come with him, but as always, Nick refused.
The main reason was that Nick's destination was surrounded by darkness, and he didn't want Aria to know that he was immune to the Nightmare's influence.
When Nick arrived at the cave system, he searched around for the cave the Big Brain Slug mentioned.
It took a while, but Nick found it eventually.
After looking through his surroundings, Nick entered the cave and traveled down.
The darkness became more and more pervasive the further Nick went, but he could still see everything as if it were bright as day… or night… that kind of didn't matter since the Sun always shone.
The cave system was rather complex, and Nick had to take a couple of detours through tight cracks.
Theoretically, Nick could just dig through the stone with his hands, but if he caused the cave to collapse, it would be difficult to find his target.
It took Nick almost two hours to get to the place the Big Brain Slug talked about since he got lost a couple of times.
But now, he was here.
Nick looked with narrowed eyes at the thing in front of him.
A metallic door.
A ruin!
The Big Brain Slug had told Nick that there was a human ruin inside the cave system, but it didn't know what was inside.
Initially, Nick didn't believe the Big Brain Slug.
After all, why wouldn't it want to look through the ruin?
However, its answer was as simple as it was logical.
"There are no humans there."
Well, Specters only wanted to grow stronger, and they needed humans for that.
There was simply no reason for the slug to look.
As Nick looked at the door, he furrowed his brows.
'This one is in a worse condition than the last one I found,' Nick thought as he looked at the crooked doors.
The doors stood at a 60° angle, and Nick was relatively certain that the builders of this place hadn't intended the doors to be angled to the side.
'I'm about five kilometers deep, and I don't think someone would want to build something this deep underground. Just getting here is a pain in the ass.'
'Most likely, this building used to be higher up, but due to something, it fell through the ground and ended up here. Earthquakes, maybe.'
Nick approached the door and touched it.
'Zephyx,' Nick thought as his hand caressed the cold metal. 'Not a ruin of the Ancient Ones.'
'This is a ruin of one of the other past civilizations.'
Over the past decade, Nick had learned a lot about the past civilizations.
Not only had Julian talked a lot about them, but Nick had also gained access to a lot of secret information after joining Aegis.
It was important that Governors knew about the past civilizations so that they could give accurate information to Aegis in case they found something.
According to Aegis, over 20,000 years had passed since the Ancient Ones had vanished.
It was important to note that 20,000 years was the lower end of the estimate.
Higher estimates went as high as 150,000 years.
As Nick touched the wall, he put more pressure on it.
The wall started to bend and crack under Nick's increasing power.
'Not very durable,' Nick thought as he reduced his power. 'There is Zephyx in the walls, but the walls are not nearly as advanced as the walls of the Ancient Ones. Nevertheless, they contain Zephyx, but the fusion of Zephyx and materials seems crude. It's almost like they just dumped steel in Zephyx and called it a day.'
'Additionally, a lot of time must have passed for this building to sink this low into the ground.'
'Most likely, this belongs to the Recovering Ones.'
According to Aegis, there had been five civilizations in this world. There was a possibility that there had been more, but there wasn't enough evidence to support that hypothesis.
The people of the first civilization were called the Ancient Ones, and their technology had been unmatched.
Weapons that could destroy continents.
The power to harvest the energies of other worlds.
Their power had been terrifying.
But then, they all vanished, and some time later, a new civilization appeared.
According to the ruins, the second civilization tried to recover the knowledge of the Ancient Ones while slowly learning about Zephyx.
Sadly, their development speed was slow.
The oldest and newest ruins made by that civilization that had been found seemed to have a bigger difference in age than the oldest and newest ruins of the Ancient Ones.
Yet, the technological level wasn't very great.
Even near the end.
While their manipulation of Zephyx had increased by a lot, their technological level had been worse than the technology Aegis had access to currently.
In fact, Aegis could also produce much better materials out of Zephyx than the Recovering Ones.
The current civilization was much stronger than the civilization of the Recovering Ones.
Nevertheless, the Recovering Ones also vanished one day, and a new civilization appeared.
The Enlightened Ones.
They were called as such due to their rapid speed of development.
The oldest and newest ruins from that civilization were far closer in age than the oldest and newest from the Ancient Ones.
Additionally, they had attained impressive levels of technology that far outclassed all the technology Aegis had access to.
On top of that, their mastery over Zephyx had also reached a very high level.
Their mastery over Zephyx was about equal to Aegis' mastery over Zephyx.
Sadly, the Enlightened Ones also vanished at some point.
The fourth civilization was called the Suffering Ones.
The reason for that name was the incredible rarity of ruins from them, and the few of them that were found were crude, small, and isolated.
The ruins spoke of isolation from each other.
Either there had been almost no humans during that time, or they had all been forced to live in isolation from each other.
The Suffering Ones had only been marginally more advanced than the Recovering Ones.
Yet, just like the other civilizations, the Suffering Ones also vanished.
And the next civilization…
Was the current one.
The current civilization, when compared to the past, was pretty advanced but not the best.
The Enlightened Ones had been more advanced in total, while the Ancient Ones had been far more advanced in terms of technology.
Due to the crudeness of the wall and the low level of Zephyx, Nick believed that it could have only been created by the Recovering Ones or the Suffering Ones.
However, if it were made by the Suffering Ones, it couldn't have sunk this far into the ground.
Nick didn't think that enough time could have passed since then.
'A ruin from the Recovering Ones, huh?' Nick thought.
'I wonder what I will find inside.'
Then, Nick approached the door.