Explaining the rating system leads to how it's observed, and one shant look further than a pivotal and extremely important thing, which is that EVERY Traveler obtains a TD or Traveler's display.
If you've ever played a video game or read a novel, then you pretty much can guess where im going with this. That's right; basically, every Traveler obtains a system.
Mind you, unlike in popular fiction and games, there is no system AI, and it's, for the most part, impossible to interact with your TD apart from issuing a few commands, as it's essentially a floating ethereal window that only you can observe without special artifacts.
In short, all a TD represents is a means to track an individual or Summon's progress, nothing more, nothing less.
Still, that doesn't stop people from worshiping it or creating hokey stories about its inception.
Apart from opening and closing it with mental commands, the information contained in the window is what makes it a vital tool for every single Traveler.
Although the Ash-Blond Lad didn't have access to his TD since he had yet to go to Genovia for the first time, he'd seen mock-ups of what they looked like an untold number of times, so he knew what to look forward to.
Here, I'll show you one of the references the Lad was shown in class the other day; in it, his class was asked to Calculate the Example's Current Rank.
EXAMPLE
______________________
Jeremy Stephans
Age: 18
Potential Quad-Star/C+ Grade.
Rank:?
______________________
Attribute Grade: ★✬
Attribute: Blink
______________________
Statistics
Attack: E+
Defence: D
Speed: E
Energia: D+
First things first, let's start at the top, name, and age; easy, simple, clear cut, but next is where the most important bit of information you have stored in your body is quantified: Potential.
This is the make-or-break statistic, as it not only references the peak of your Attribute power but also how high you can reach Rankwise before you are stuck and can't progress further.
In the case of the example, his Attribute has a Quad-Star cap, meaning four stars, and C+ is the highest he can reach naturally…don't worry; I'll get into that later.
Up next is the Traveler's current rank, which, as you can see, was left blank because the class was supposed to solve it, but moving along, we can observe not only the Traveler's current Attribute Grade but also what this Special Skill is, which as you can see is called blink.
Basically, it's a short-range teleportation skill.
Lastly, there are four stats that everyone lives and dies by: attack, defense, speed, and Energia. The first three are pretty self-explanatory.
However, Energia is something many can't wait to experience. Mind you, if you've played PLENTY of video games, read hundreds of novels, and watched an ungodly amount of television, then It should be easy to recognize that…Energia is Mana, Magic Power, Ki, Qi, or whatever you want to call it.
It's something that is present on Terra but in a MUCH smaller amount than it is on Genovia.
Although Energia is present in the Air and in basically everything on Terra, that doesn't mean Mundanes are able to wield it in any way.
What I'm saying is that only the Travelers and all the natives of Genovia are able to wield Energia, using it to empower themselves and their combat moves or attacks; as such, it also strengthens their bodies to a "super-human" extent.
One thing to keep in mind is there is a finite amount of Energia here on Terra that has been deposited over time by the opening of Flumes all over the world. In contrast, it is commonly thought to be infinite on Genovia.
Think of it like this: Genovia is the ocean, the Flumes are estuaries, and Terra is a giant lake fed by the Flumes.
If, for some reason, we were ever cut off from Genovia entirely, it would take some time, but all of the ambient Energia on Terra would eventually disperse.
Since Energia is not native to Terra, this is also the primary reason why Mundane Terrians are unable to survive the flumes. Their bodies, while able to handle minute amounts of Energia, much like with any other type of radiation or energy, will break down in seconds once subjected to the massive flow of the magical essence upon entering them.
SOOO, back to the example TD, although the System automatically calculates your rank, that doesn't mean you can't plan out your Ranking progression; in fact, it's quite easy.
Long ago, several scholars figured out a simple equation and made a table that can be used to calculate rank.
All you have to do is take the numerical value assigned to each letter, add them together, and divide them by four; it's pretty simple, right? Here's the chart.
(Example Ranks: Atk: E+, Def: D, Spd: E, ENA: D+)
R | - | Base| + |
G | 0.5 | 1.0 | 1.25 |
F | 1.5 | 2.0 | 2.25 |
E | 2.5 | 3.0 | 3.25 |
D | 3.5 | 4.0 | 4.25 |
C | 4.5 | 5.0 | 5.25 |
B | 5.5 | 6.0 | 6.25 |
A | 6.5 | 7.0 | 7.25 |
Using the chart, you get the following values: 3.25, 4, 3, and 4.25, which adds up to 14.5; from there, you divide by four since there are four stats and BOOM, the Examples Rank is 3.62 or D-. (If it falls between numerical values, you round it down.)
I can't tell you why or how those scholars came up with the numbers or how to decipher them, but that table has been taught for thousands of years and is the Gold Standard when it comes to calculating Ranks.
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Looking down at his feet, the Ash-Blond Lad shuffled forward while running through the many plans he had spent his short life developing in the event that he awakened into a Traveler.
'Shelter and flume first, then I can worry about my Ratings; although nothing can enter my territory for the first month, that doesn't mean the terrain I land on is stable or safe.' The Lad's eyes flicked up momentarily, and he noticed that his time to enter the Flume was Rapidly approaching.