The idea is to have a small, shitty station on a large lavaland map, where the game mode is to build, expand, mine, and explore.
Here is a picture of one of d20s dorf mode maps, to give an idea.
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What is circled in red was the outline of the original starting station, and the rest was expanded upon, built by players, by hand.
The basics;
Dorf mode is a long, long mode; d20 dorf mode rounds usually were up for the entire weekend, although a part of that was just to see how long we could keep it going for. Dorf mode would also be on a larger lavaland map, bigger than 255x255, as multiple traversal z levels would not work out too well on a planet. There would be no normal player antags; no traitors, no changelings, no wizards, no nuke ops, no cultists, nothing. Dorf stations are too vulnerable early on to sabotage. Thus, there is no security, as almost all players are armed and ready to fight wildlife that gets close to the station. For here, with the more dangerous lavaland, I would imagine a security defense force would not be too far out of the question. More things were orderable via cargo, or could be found in loot rooms, to help build up the station, such as chemical dispensers and such.
Things that would need to be changed;
With lavaland, there are a few current issues. The first is megafauna; having someone be able to lure a drake or bubblegum or collosus to the station to cause major damage would not be that fun. I propose for this map, then, a area of the map is made to be a destroyed necropolis, which requires some long process to be able to gain access; all current megafauna would reside in there. This would keep people from luring them to an early, budding station, as well as stop people from trying to get their loot early on.
Tendrils are another problem. With a large map, or just with a lavaland based map in general, there would be a LOT of loot lying around from tendrils. Thus, I would propose for this map only, tendrils would spawn lesser/no loot, and can pop up during earth quake events. This gives people something to fight.
For this map, there may need to be modifications for jobs; d20 removed several of the lesser jobs, keeping only essentials, as well as removing security. As well, cargo would need some new crates exclusively for this map, for the purpose of building up the station.
The problems;
The big issue is time. Dorf mode was usually run once a month, for a weekend. It usually was just one round for that entire weekend. I know people will have an issue with rounds this long, both with how boring it may get, as well as scheduling it.
Another issue is rules; on d20, there was no pvp, as everyone had to work together, and it was all so vulnerable, especially early on. This means that there was not a need for security, nor were their antags, and people trying to grief or fuck with others were usually talked to by admins. These things, I would imagine a lot of people will have issues with.
Another problem is with the game mode itself. Not everyone likes to build. A lot of people will be turned off by this whole idea solely because it is based around building and expanding. A larger lavaland map, to give people something to explore and fight, would help, but other than that, I really do not have a solution for this.
I would like to hear peoples thoughts on this, to see if anyone is interested in it. I do not know how hosting this would work, but I would imagine that something could be done if there is enough interest in this.