Adapting Existing non-RPG Settings for your Home Game
A lot of us like to homebrew our settings, or play in official TTRPG settings built from the ground up to work with whatever system we choose to run. While I love a good TTRPG setting like Vaarn, Dark Sun, Dolmenwood, Cloud Empress, I’m not really talking about porting those over to other TTRPG systems, although running those settings with games they weren’t designed for is its own interesting topic.
What I am more interested in talking about today is taking a setting from another piece of media and the challenges of adapting it to run a game in there. It’s something that’s been on my mind since I wrapped Uncanny Earth, which was my homebrew MCC setting which stole its lore from X-Men comics, and right now I am playing in a Daggerheart campaign that takes place in Runeterra, from League of Legends.
Overall, I would actually really recommend doing this for your home game (provided you don’t intend to profit off of it), as I think it can be a great shortcut to providing a cultural touchstone for the table, and the GM doesn’t need to invent a whole bunch of lore or setting details. That said, there are some things to consider before jumping fully on board the hype train:
1) Does this setting already have a licensed TTRPG system or supplement?
Ok, so let’s go with an obvious one and say you really want to run a game in Middle Earth, but aren’t sure which system to go for. You’re in luck. Countless designers and publishers have already thought of this, both in the indie space and in the mainstream. If your table likes 5E and won’t play anything else, you have The Lord of the Rings 5E, published by Free League, which adapts the world’s most popular roleplaying system to match the themes and content of Middle Earth. But if you wanted something more bespoke you also have Free League’s The One Ring.
Those are both great options but what if you prefer rules-lite games, or a more OSR playstyle, then you also have the indie space to look to. While not officially licensed, DedZeppelin’s Wilderlands RPG is a neat Mark of the Odd game that aims to capture the original setting of The Hobbit, and evokes that specific tone in its mechanics.
But perhaps none of those options are quite right for you. Maybe you have a specific vision of matching a system with a setting that hasn’t been done yet. Maybe your ideal setting is not so well known to have official or unofficial adaptations already. What then?
2) Find a system that matches the themes of your setting
To continue with the example of Middle Earth, it might not be the best choice ever to run that setting using Lancer if you wanted to retain the themes that setting is evoking. I know that’s a very extreme example, but it is illustrative of a broader point: systems reinforce theme and tone.
For example, while I could feasibly run a Shadowdark game set in Middle Earth, the structure of that system will push the themes of survival and dungeon crawling to the forefront. That may absolutely be what you are going for though! And some settings allow for that verisimilitude. It may not be entirely true to Tolkien's version of the setting, but it’s not like the setting will fight against what the system is going for. But it is worth noting that the game’s mechanics will change the tone, even if slightly.
I wouldn’t run a Cairn game in Azeroth (World of Warcraft’s setting) for example, because that’s a high-fantasy, high magic setting where characters are big-damn-heroes. Tonally there would be a disconnect. However, I could imagine someone running the setting using Draw Steel, or Daggerheart even, since those games support that kind of fiction really well. Still, there will be patches to smooth over in that transition.
3) Adjustments will always need to be made
Because we are dealing with settings that were never designed for the TTRPGs we want to run them in, we will always need to make some adjustments to the game system of choice, or perhaps even the setting.
This requires knowledge of both the system and the setting to really get the right balance going, but I wouldn’t be too concerned with that when just starting out. The parts that need adjusting will really come through during play more so than just ideating. Still there are some easy catches.
If a setting calls for a more heroic tone than your system of choice, it might not be the right move to abandon that system altogether. At the end of the day your familiarity with your chosen system is probably giving you the confidence to even run the setting this way. Or maybe you are just really hyped about the system in general. Both are valid reasons. Luckily, making characters feel more heroic isn’t that complicated in the grand scheme of things. Maybe you just need to bump up everyone’s HP, or perhaps you could include meta-currencies like Hero Points, which allow for re-rolls. Maybe it’s character death that needs reworking.
Whatever it may be, my advice would be to scour the broader ecosystem and discussion around your system of choice to see if anyone has already figured this out. With things like more heroic characters, you are likely already going to find a fix. Firearm rules are much the same, since they come up a lot in adventure gaming. Generally someone has already explored the idea of using the system in a genre it was not intended for. Maybe the game’s designers have those rules published somewhere already, as was the case when I stole Fleeting Luck from DCC Lankhmar for use in my MCC campaign to make the PCs feel more heroic.
For a more advanced approach, it’s worth looking at how other systems handle the thing you are looking for. This may take a bit more tinkering if you are adopting a mechanic from a completely separate system, but many systems do have modular gameplay mechanics that are easy to plug into any game. Even if you aren’t a fan of your setting’s official supplement/TTRPG it may be worth to read it anyways to see how they handled a specific setting problem. Even without that, looking at other games that operate in the genre you are going for will be a huge help.
4) Don’t be afraid of contradictions
My final piece of advice would be to accept that you won’t find that perfect combination, and that the contradictions or points of friction might actually lead to a more special experience. In my own MCC game, I knew that the system I was using was not designed for heroic/cinematic combat that is so integral to the superhero genre, but that’s actually what had me excited about running it in the first place. I wanted to have a different take on this setting. One where the main characters were powerful, but not particularly heroic. It’s something I embraced as the campaign took shape, because the system was pushing the game in that direction. Rather than fight it, it’s worth embracing it.
If you are having fun with the system. It’s worth changing the fiction. At your table, you own this setting, not the IP holders, so anything goes. Maybe in your version of Azeroth, the players aren’t the big heroes, but rather the normal folk who live in their shadow and clean up their messes. Maybe your Mothership campaign set in the Star Wars universe is focused on the horrors of living in a galaxy far far away. Maybe your Middle Earth has mechs in it because you freaking love Lancer AND The Lord of the Rings, and you have a VISION. That’s the most important piece of the puzzle here.
So if you find that you are enjoying the way your game is shaping up, but you aren’t exactly keeping with the lore or the canon, don’t sweat it. It’s not your problem. Just keep running your game, because you are inevitably going to create something new and more interesting than what has been done before.