I tried steampunk Halloween. I ended up not having the vision to really make it work. However, my version wasn't too scary. Somethings I'd suggest are old rusty steam pipes, boilers and gears. Victorian elements added into the mix. I was going for more of a cartoonish kid friendly theme but I definitely think a dark and ominous haunt could be really cool. Something like those old death masks or other odd Victorian creepy stuff with the cool crimson, rust and deep purple color tones added to the mix.
Steam pipes I made
The steam boiler
Some gears on the clocktower
Here's this year's thread for the Steamtown Gotham stuff.
Since a lot of people are at home checking things on the internet I thought now would be a good to do some updates and post pics from Halloween 2019. Also I'll post progress pics and build stuff as we get closer to Halloween 2020! The addition of the green warehouse, also known as "Ace...
After trying to make the steampunk thing work for a couple years I ended up making it into a alternate universe Gotham theme with a mild steampunk vibe and called it Steamtown Gotham. One thing that was a bummer about the steampunk thing was that people really didn't know about steampunk. Especially the first few years. The people who knew about steampunk really dig it. But if you are successful in doing a really awesome scary version I think people would really be into it regardless if they know steampunk or not.
A scary steampunk would be really cool so I hope you make it work because I for one would love to see it done!