Shadow World

s were a kind of parallel worlds and the most dangerous phenomenon mankind has ever seen that occur each year. Like an infinitely long corridor with countless rooms on each side; there are countless worlds, each with their own bizarre set of rules.

The s are divided into 10 levels, and depending on the ranking, the number of deaths in a can be estimated.

Without a doubt, however, the most dangerous characteristic of a is its potential for an ‘Encroachment’ event to occur. Encroached land is smothered in a thick, black fog, and it becomes impossible to know what’s happening inside. Only one thing is certain: no living being has ever entered encroached land and returned alive. It is simply a place where life cannot exist.

Clearing the
‘Clearing’ the prevents it from encroaching upon our reality. If the event of a given is based off of a past war in our world—the ‘background’—and the victory of that war consisted in demoralizing the enemy, then the ‘clearing’ would involve defeating the enemy in the exact same manner—this would be the ’s ‘objective.’ Every  has its own background and objective, and completing that objective ‘clears’ the.

The goal, then, is to clear all the s that appear. And the two rival organizations, Western Kingdoms and Havrion Academy, stand at the forefront of this movement.

Class 1
Class 1 are the strongest and most dangerous s.

The Shadow Labyrinth that occurred in the Year 3616 was a Class 1 Shadow World. It took 150 million people and 10 years to be cleared. If another of this scale were to appear again, it would definitely be the end of the world.

Class 2
Until the Year 3613, there were no reported incidents of Class 2 or higher s.

Class 3
Class 3, for all intents and purposes, was the highest difficulty.

Class 5
From Class 5 and above, those who entered the s will be exposed to war and murder. Death is a very real possibility.

For a 1st year Single Ranker, it’s normal to enter a Class 5.

Class 6
Class 6 and below s are fairly easy that just about anybody can clear them.

Class 10
Class 10 are the weakest and least dangerous s.