What made this power system the most popular wasn't even related to the "core" thing.
Rather, it was about the fact that this power system could include, or adapt to, anything.
It's to the point that, if one wanted, it could be as straightforward as they liked… or as complex as they could possibly imagine.
If someone just wanted to become a pure warrior, focusing on brute strength and destructive power, they could.
If they wanted to wield flames with explosive techniques, or manipulate others with illusions and hypnosis, or even tap into things like time, space, or gravity…
This power system could do it.
As long as it fell under the attribute they trained in, or attributes, since some techniques could have multiple ones… then, it's possible.
One just needed to choose an attribute or a bunch of them early on and stick to it.
Because once someone set off on a path, changing their mind later meant starting over from zero.
And while that shouldn't be entirely impossible to fix, there was no need to go through that hassle later, if possible.
It was still better to select an attribute and concentrate on it from the beginning. After all, people didn't have his idle system backing them up.
Christian explained all of this, and went into even more detail, wanting to make sure both his sister and Eva fully understood.
"So, for this power system, since I'll personally create a technique for you, you will get to decide everything. Just tell me what you have in your mind, and I will design a technique for you." He said, while looking at his sister as he finished… at her excited and fascinated eyes.
He thought that after hearing this much, and from her reaction, she was probably already too hooked. As really, after he got to understand this much about this power system… and how amazing it could be, Christian also started to look down on his current Breath of the Shadow Blade technique, and wanted to change it.
Even then, he still didn't change it… because the idea for the technique he had in mind for himself, it was so overpowered, that he was certain he would need a long amount of time to create it, and more so, of researching materials.
His current digital library… his knowledge bank, despite how many essence techniques from many different power systems it held, they were all too low-leveled after all. So they were not that helpful.
"Then, what about the other Power Systems? If there are still people using them, then they should have something this one doesn't, right?" Annabelle, who had been silent and thinking, suddenly said.
"… Well, how should I explain it? While there are actually many power systems out there, not many of them have the same classification, the same standing as this one," Christian, while trying to sort his thoughts, started.
"And if I break things further down, to what I defined as main power systems, then there are actually just two more. With the many others being just derived from these three."
… Of course, this didn't mean there weren't any exceptions.
"… Naturally, there are some unique power systems, that are not in the same category too."
"As really, they are just… too unique."
Arriving at this point, and seeing his sister and Eva's curious eyes, Christian, while chuckling to himself at their cute reaction, started explaining.
He needed to spend more than three hours explaining things to them, even when there were some power systems he brushed over entirely.
One would wonder… where did all this information come from? Was it really all online? In some confidential database of some countries?
Naturally no, it was not that simple.
While some pieces of information was actually uploaded online, in the end, most of it was unimportant. The really important parts were just that much harder to come by.
… But, after his skills advanced this much.
With his current ability standing at the forefront of humanity in regard to things like programming, encryption, and system manipulation… so, things changed.
Christian had already started to investigate all the people around the world, and while he began with suspicious individuals, he was still extending his reach… for what?
To mark anyone who had come in contact with essence.
To mark anyone who was possibly from another world, and who was actually also using a phone, or any device with the access to internet, just like any other native person.
… And then, he would eavesdrop on everything!
Naturally not he himself, but some programs he created, with Iris also monitoring things, then filtering and sorting everything.
Finally, the information would come to him.
Many kinds of information here were ones he got through overhearing bits and pieces from these kind of individuals!
… Was he not transgressing others' privacy with his actions too much?
Well, he was… but did he care? Most importantly, when it really came down to it, he didn't know any of them, and never even bothered about a single detail. As the only thing that would come to him, was details related to essence.
… So, was he this overpowered when it came to information gathering now?
Unfortunately, it's not that convenient… it's not to that extent… yet!
As for the really strong people, he is also unable to eavesdrop on them at all.
Any kind of device, when it comes into proximity with them, will stop working after all. So, he is still limited in how far he could extend his reach.
Still… it wasn't all bad.
That very limitation ended up helping him achieve one of his goals, after all.
Because due to this point, Christian was now able to mark some high-risk individuals, ones that, no matter what, he shouldn't come into contact with.
After all, if he couldn't use devices near them… then he could just use distant ones.
Even then, he didn't dare go too far. They were dangerous, after all.