I’ve run four campaigns in an original interdimensional steam fantasy setting, the worlds of Mistrathe Manor.
Cosmology
Mistrathe Manor is located on a world that is part of an interdimensional network of many such worlds, no two exactly alike. Many of these worlds connect to others via Gates. There are also higher realms, as well as lower ones, each with its own properties, and these realms are in levels, from lowest to highest: Void, Substrata (underworld), Strata, Between, High Road, Heavens and Unity.
Lower realms (the Void, The Substrata and the Strata), don’t differentiate into individual worlds. Thus, there is only one Void, one Underworld, and one Strata, and you can travel within each environment.
The Void is a black emptiness, extending forever away from the Wall, mostly in vacuum. There are lost spirits wandering in the Void, as well as exiled beings. The Void is also where the most dangerous beings are imprisoned, in floating rocky prisons, far from the Wall.
The Wall is the boundary between the Void and the Substrata. This has no entry points, and can only be accessed by powerful essence beings pooling their energies to phase down into the Void. The Wall is almost completely without leaks, but there are a few tiny hidden unnoticed cracks where spirits can get through in either direction, if they know the way.
The Substrata is black and rocky, and riddled with tunnels, filled with mostly breathable air. The Underworld sometimes widens out into bigger caverns, some of these inhabited. The larger of these are also called Hells, and are usually where infernal essence beings are found. In places, the tunnels of the Underworld reach into the Between in places, bypassing the Substrata.
The Between is what we would recognize as reality, where individual worlds differentiate, in a way floating on top of the lower realms. All of these worlds are like the Earth we know, with the Moon and the Sun and the stars all recognizable, but the geography of each world is different.
The Between can be reached directly from the Strata, and vice versa, if you can manifest the ‘skin’, and pass through it in either direction. By moving through the Strata, you can get adjacent to another world, and pass through the skin into that world. Some places in the Between (usually deep caves) also connect to the Substrata. The Substrata and Strata do not connect to each other directly.
Creative Journey
In the mid 90s, I had just wrapped the first phase of a very successful and popular campaign using Wujcik’s Amber Diceless, originally from Phage (now only available from Diceless by Design). We were all Zelazny fans, and I may post an article about that campaign, The Chronicles of Onyx, about the children of Eric.
At about that time, I picked up copies of both Castle Falkenstein and Whispering Vault. Though I never ran either of those fantastic games, I was inspired by them, especially the former (still in print), and by our ongoing Amber campaign.
I started crafting a cosmology for a steam fantasy setting, and while it was pretty derivative at first, it also had a lot of cool things about it. Eventually, I named the setting after the headquarters of the characters, Mistrathe Manor. It was fun. It put a lot of time in, and players liked it.
Back then, Wayne had been branching out from our original crunchy home brew, and had a minimalistic narrative system dubbed the Short System. I adopted it for the game, as we wanted it to resemble Amber to some degree, and that system is very narrative, and counts on players to help generate a lot of the ideas. It worked well, and we played for about a year, alternating with the Amber sessions.
After we had reached a stopping point, my brother suggested I write fiction set in one of my games. I began a novel set in the worlds of Mistrathe Manor. I actually finished the first draft many years later, but writing is revision, and I ran into reviser’s block. Maybe I’ll return to it, but games are my passion, so they have priority.
A couple of years later, we ran another campaign in the setting, beginning the characters at a lower power level, still using the Short system.
About ten years later, I ran another group using an updated version of our crunchy Core rules. That only ran for about six adventures, but our group began another game of World in Flames about then, and it ate our brains for a year. Wayne continued to run his Winter World campaign using the Short system during that time, to keep our roleplaying itch scratched.
After that, more than ten years went by, and while I continued to design games, I didn’t GM anything.
Then, at the beginning of the pandemic, I decided to run a VTT campaign set in the worlds of MM (centered on a different world than that of the earlier campaigns). That was using the Short system again, and playing virtually over Roll20. We only had four players, because at least three of our group were dismissive of VTTs, but it was enough to develop quite a story, so that when we resumed in-person play, we just picked up that group and added some new characters. That campaign was a rousing success, running from 2021 to 2023, usually twice a month. It was during that time that Yarn began to form in my mind, as a middle ground between our two earlier home brews, while incorporating some modern ideas.
When we return to Mistrathe Manor, it will be using an updated version of the Yarn rules.