For some clarifications about my universe, here are a few questions I can answer:
What exactly is STOYDE? How can we define this planet where humanity took refuge?
Stoyde is a purely fictional planet on which humanity was relocated after the invasion and destruction of Earth.
It is not a dying world, but rather a land where technology has reached a new level by merging with magic. To give a clear image, imagine our old world, but with far more advanced magical technology. Flying vehicles exist and magical science is everywhere, yet the planet remains balanced: there are still natural lands and spaces to breathe. It is not just a block of metal and concrete.
How does light work without a sun on this new planet?
This is one of the major characteristics of Stoyde: the sun does not exist. There is no solar star, and yet it is not always dark. Light comes directly from the sky itself. The sky generates this ambient brightness, and most people call it the light of the constellations.
The time cycle still exists, as night does indeed occur. Note also that it never rains on Stoyde.
Why is the term "Cleaners" used to describe the fighters?
They are called Cleaners because their role is to cleanse the Earth of the monsters that infect it. Following the invasion, these creatures gradually built strongholds: Dungeons. Although these dungeons exist in another layer of reality, they are still located on Earth. A Cleaner's job is to enter these strongholds and eliminate the threat at its source.
How is the territory organized in relation to monster danger levels?
Everything is segmented into danger zones corresponding to dungeon ranks. The lower zones range from rank F to rank E. The intermediate zones contain rank D to C dungeons. The higher zones contain rank B to A monsters. Finally, there is the Nightmare Zone, which is the territory of dimensional monsters of rank S.
Are there power items, and how does the economy work on Stoyde?
As for the economy, everything is based on Credits. This is the currency everyone uses. As for items, we use Artifacts. Like the zones, they are classified into categories to define their power: inferior, intermediate, superior, and finally legendary.