Scope
Mundus's Unique Selling point
There are two big concepts that I hope will hook people into the concept of this world.
The first is that the setting is a little more technologically advanced than your classic D&D setting. It lies in the midpoint between the more traditional fantasy of the Forgotten Realms and the more pulpy Sci-fi fantasy of Eberron. This is because I've always been drawn to the visuals of properties like Howl's Moving Castle, and Disney's Treasure Planet, and I've always wanted to create a setting that borrows from these aesthetics.
The second draw in my mind is how I've distinguished my world's outer planes, which also ties into the themes of the world itself. Rather than following the traditional D&D alignment chart (of Lawful Good, Chaotic Neutral, Lawful Evil, etc.) I thought the realms can be juxtapositions between the concepts of Order and Chaos without necessarily being tied to any one type of morality. This was in a way inspired by the idea of achieving balance and that too much of either can be dangerous. It also was a way for me to not feel constrained to the archetypes of the holy Angel and the foul Fiend, and allow me to create characters that can fit into the conventions of this setting without having to be a total deviation for what that type of being would stand for.
This also necessitated that rather than having some plane of pure order like mechanus, the Material Plane would end up being the plane of true neutrality in this world.