Short Princess of Mars update.
My taste for the design of the alien cities of Mars runs more towards the Al Williamson and Frank Frazetta aesthetics rather than much of the modern sci-fi that is being done these days. While I am amazed at how incredible futurist concept designs have become, especially with modern 3d tools. I still like that old time rock n' roll.
When it comes to designing something new, yet interesting and believable I always like to look to real world objects and see how I can use them for inspiration. In this case brass decor and other miscellaneous household objects come in a wide variety of shapes that I could imagine being alien cities. And it also reminds me of the sci-fi architecture in the art of Williamson and Frazetta.
Here are just a couple of pages from my sketchbook of ideas for Barsoomian city buildings. And then I took one of them and designed it further into an adventure map.
Here is a sideview of one of the buildings. Reminiscent of those sideviews in the original and Basic books that were so good at stirring up ideas for adventure locales. I'm considering whether the buildings should be keyed with descriptions, adventure hooks, creatures, tricks, and traps or left more open sandbox for the GM to customize. Probably a mixture of both.
The elevator shafts could be powered by some strange tech that the players will have to figure out how to activate. Or natives may know and just have to get it up and running in ruins, or solve the security code to active. In this building the shafts are put at opposite sides of each floor to encourage exploration.
I still need to work out the plan (top down) views of the levels. This task could turn into an overwhelming challenge with hundreds of designs and maps, so I will necessarily have to keep it reasonable in scope and only draw what is needed for the GM to be able to run the adventure. And this will set a template for the creative gamer to use the format to come up with their own great alien city adventure maps.