The World of (Un)Holy Crusades

The world in which the (Un)Holy Crusades take place is occasionally referred to as "the Five Realms," but has no proper name, because there are no other worlds aside from that one for all its inhabitants know, therefore it does not need a name to distinguish itself. The world exists as five giant, parallel round discs of approximately the same size stacked on top of each other, all levitating within an endless white void through unknown means. These discs are referred to as "realms," and it is nearly impossible to traverse from one realm to the next without the use of magic.

The Five Realms
Each of the five realms are almost completely different in appearance and environment, but all of them are exactly 8000 miles in diameter, with the only exception being the "bottom-most" realm, the Realm of Chaos, which is 8666 miles in diameter.

The Realm of Thoughts
The Realm of Thoughts is the top-most realm in the world, and thus it is directly exposed to the infinite void around it with no visible sky or day-night cycle. This realm is completely barren, and its top surface is made entirely of a smooth, dark stone-like material. There is no air, water, or life to speak of in the Realm of Thoughts, making it impossible to survive outside of a few select structures that inexplicably exist on its surface. This realm also has a bizarre, possibly magical effect where only those who have physically been there or personally witnessed it with their own senses can remember its properties and appearance. For example, if someone tried to describe the Realm of Thoughts to another person who had not been there, then the latter would forget what was said immediately after hearing it.

The Realm of Thoughts is only accessible through Checkpoints.

The Realm of Order
The Realm of Order is the "second realm," immediately below the Realm of Thoughts. It is known to be the most secured realm out of all five, being almost completely impenetrable unless deliberately led into it by the Sovereign's Sentries. The Realm of Order serves as an afterlife for the souls of all those who tried their best to adhere to the Church's laws and praised the Sovereign earnestly in their lifetimes. The entire realm takes the form of a giant, palace-like building full of guest rooms, theaters, arenas, pools/baths, and banquet halls, where its chosen inhabitants can live out the rest of (presumably) eternity in luxury amongst like-minded peers, their every conceivable need served and fulfilled by the Sovereign's Sentries.

There is breathable air in this realm, and edible food/potable water would continuously refresh in its banquet halls, but there are no living things aside from the souls of its inhabitants, and the mechanical Sentries.

The Sovereign Himself resides in this realm, but even its inhabitants have never seen Him appear in person. This realm is also accessible via magic, but anyone caught doing so will be treated as an intruder and attacked by the Sovereign's Sentries.

The Realm of Materials
The Realm of Materials, or the Material/Mortal Realm, is the "third realm" directly below the Realm of Order, containing the mortal kingdoms of Astrea and Miasmial. This realm is almost identical to the real world, featuring a massive ocean covering its surface, two giant land-masses that make up the kingdoms (each with its own diverse climates and biomes), and various forms of living organisms.

Magnetic fields also exist on this realm for inexplicable reasons, and "north" is recognized as its center, while "south" is recognized as its edge. West and east are completely arbitrary.

Despite its lack of rotation around celestial bodies, there is a day-night cycle in the Realm of Materials, facilitated by a massive, shining orb attached to the bottom of the Realm of Order. This orb will gradually dim its light over the course of 24 hours, and reveal smaller, similar lights known as "stars" at its dimmest. Due to its dramatic shift in brightness throughout the day, the orb was originally thought to be two separate entities (the Sun and the Moon) in ancient times, and still referred to as such in the present (depending on whether it's day or night time) because no one could agree on a better name for it.

The atmosphere in the Realm of Materials is also breathable, and refreshes itself/creates wind and weather/facilitates the changing of seasons through no discernible mechanism. The water/ocean in this realm also stops at the edge of it instead of leaking towards, blocked by a giant, invisible wall that freezes anything it touches in ice. The "equator" of this realm does still exist as a circular line exactly halfway between the realm's edge and center, and is still warmer than other parts of the realm, but this once again seems to be a completely arbitrary feature with no logical mechanisms behind it.

In other words, almost all laws of physics and common phenomena observable in the real world can be found in the Realm of Materials, but unlike the real world, many of the mechanics and scientific properties that power their existence is missing.

This realm is accessible through magic, and not everyone living in it is aware of the existence of all the other realms, seeing as the Realm of Thoughts and Dreams are highly difficult to explore and describe.

The Realm of Dreams
The Realm of Dreams is a surreal, psychedelic place below the Realm of Materials, which the souls of mortals are transported to while their bodies are asleep. This realm resembles the Realm of Materials, but contains its own unique flora and fauna, some of which would not be able to naturally exist in the Realm of Materials, such as rubber trees that are actually entirely made of rubber. Not much is known about this realm, because it has a memory-erasing effect similar to the Realm of Thoughts, where most people's ability to remember what took place in this realm during their stay after they leave is inconsistent at best and nonexistent at worst. This realm is inhabited by fairies and related creatures, and has no kingdoms like the Realm of Materials. Rather, fairies seem to organize themselves into different types of micro-communities, some of which are beyond mortal understanding.

This realm is accessible through magic, but magic functions differently while within this realm, so it would be far more difficult to leave it through magic.

The Realm of Chaos
The Realm of Chaos is bottom-most realm beneath the Realm of Dreams, and serves as the afterlife for souls who did not obey the Church's laws or praise the Sovereign. These souls are placed into a world consumed by eternal darkness and left to their own devices. The souls who enter the Realm of Chaos become demons, and gain magical abilities based on their personality traits and desires in life. These abilities are often the only means for demons to survive in this realm, because it lacks all natural resources, including light. Because of the environmental nature of this realm, demons are known to use magic to invade the Realm of Materials and steal its resources for their own use, seeing as they have no means to produce it in their own realm. The demonic invasion from 500 years ago completely destroyed Miasmia, and another one is progress in the present.

The Realm of Chaos is ruled by seven devils, who each represent a facet of negative mortal personality traits discouraged by the Sovereign, but not all demons obey their rules, with some choosing to go rogue despite its disadvantages.

This realm is accessible through magic.