I've had an idea, I thought I'd share it and if you like you can add to it. It's not a fully fledged project like Urban Planescape, so feel free to shout out any idea you have.
Here is the deal:
Traveling through the planes is a colossal steam train, which is even more titanic inside, housing thousands of travelers and even native creatures. Some carriages are forests, some cities built on cities and others with different laws of nature!
The Locomotive is driven perhaps by an aspect of the God of Travel, or even the God of Travel in a purer form than worshipped elsewhere...it could even be Aoskar.
No other God has a realm with the train, but perhaps you might find an old or dead god hanging out in a café or bar.
The Locomotive travels the planes constantly, making the occasional stop to let off travelers or just to let some folks explore the land. The Driver can even be asked to travel somewhere...but where he goes is his own business.
The different carriages of the Locomotive could even be considered demi-planes in a sense, not infinite, but each is very large.
So far I have:
The Drivers Chamber, very beautiful marble arches and pathways with paintings of many past eras, places and people. Much like Sensate Stones the painting can be touched to get a feeling or a moment. Castles hang in the air, inside live many powerful and ancient creatures that have left the planes for solitude. Some even swear to have seen the night hag Ravel in one of these castles, but she was Mazed years ago...
Following the paths leads to the Driver, merrily pulling golden gears and spinning wheels.
The Engine Room, much like a rusty, smog filled Mechanus. Thousands of workers, from golems to more magically inclined dwarves make sure the Locomotive keeps thundering through the planes. The train is held togethor on ancient and loosely defined magics, and with Far Realm spirits constantly slithering through the vents its a full time job for the Crew.
The Crews Cave-Home, under the Engine Room are uncountable maze tunnels crammed with little grottos and cottages. Travelers are warned not go in their alone, many nature creatures that leave the crew unharmed might not do the same for others...
The Wild-Top, on the top of the train is a mix of strange beings and terrain, few things can live through plane-to-plane travel, the few that can live here. The terrain is different every few miles, sometimes every few steps; dust from the Grey Wastes floats in the air, confused lightening elementals jolt from one stop to another and even puddles of enchanted Bytopian water can be found up here. If you can climb the side to get there that is...
The Sleeping Car, people have been asking why there is sleeping car when every city in Divine Locomotive have their own sleeping chambers. Truth is no one know what sleeps in that dark car filled with stacked containers of black metal. Containers are definetly not cargo because when all Locomotive goes to sleep and things are silent, the deep breathing of sleepers can be heard from within.
What sleeps there, nobody knows; some say they are pasangers who wait the last stop of Divine Locomotive, at the end of the multiverse.
One thing is for sure, folk who wander alone too long in that area are never heard of again, so the area is avoided by all except conductors, and even they go there in pairs.
A general idea of the train, all I know for sure is the place is controlled from the front section, the middle sections will have more cities and lower level adventures, the back end having more dangers and beauties.
Lists of ideas for native creatures go here;
The Crew
Conductors - Calm justice dealers and pranksters, they share a likeness to angels mixed with devils, but come in much more muted colours
Marble Maids - Lawful awakened marble golems, but they move in a much more light fashion
Dvergar - Little magical Master-smith dwarves that can fix almost anything...for a traveler though, it'll cost
Wild Natives
Kentiways - Talking crows
Soot Children - Engine Room mephits
Gear Spirits - Can be found doing seemingly random things like turning off lights and rearranging chairs.
The Butterflies in the Walls - Ancient Far Realms creatures that bend the walls into shapes to frighten intruders. The creatures are in fact tiny.
Current DnD monsters that could appear
Blink Dogs, as guards and sniffer dogs
Goblins, living in hideouts in dark corners
Steam, Fire and Earth Elementals, byproducts of the Engine Room
Powerful NPC travels
Nilaihah, the Poet-Angel - A Solar said to operate in Heaven & Hell, he leaves the train when it gets to the Abyss, say's what he has to then jumps back on and waits to get off at one of the high planes.
Konth - Once the God of Konthing, Konthing as since stopped existing. He is usually found playing cards, which he says is very much like Konthing, but without all the Barrads and Snids.
I like Divine Lokomotive idea, so here is my idea. Hope you like it.
Sleeping Car:
People have been asking why there is sleeping car when every city in Divine Locomotive hawe their own sleeping chambers. Truth is no one know what sleeps in that dark car filed with stacked containers of black metal. Containers are definitly not cargo becaouse when all Locomotive goes to sleep and things are silent the deep breathing of sleepers can be heard from there.
What sleeps there, nobody knows: some say they are pasangers who wait the LAST stop of Divine Locomotive, on the end of the multiverse.
One thing is shure: folk who wander alone too long in that area is never heard of again, so area avoided by all except conductors, and even they go there in pairs.
One-eyed, one-horned, flying, purple people eater says: "Monsters are nature's way for keeping XPs fresh."