What legal issues will I have with copying themes and ideas from existing RPG's?

Question

So I've ben building a tabletop RPG for quite a few years, gone through all the mechanics, we have a timeline laid out for doing a TON of playtesting (individually, local friends, local game stores, maybe even online) as well as how we'll probably release it (rules are free, books are not, expansions to extend specific settings, skill arenas, etc.), and now I'm working on filling out some of the semantics.

We built it from the ground up, so I'm not too worried about mechanics. That was one of the main ideals, in fact - because we don't like the typical d20 setup, and we want it to be fairly unique, strategy-based, etc. Of course, since I've become more experienced and looked at other games, and it basically confirmed what we've learned on our own over the years and intervening iterations. (Happened sorta like convergent evolution, which I still kind of geek out over.)

One of the other main ideals is that, like GURPS or similar, you can play it using any setting, 'power source', or theme. And now I'm working on filling out 'example lists' to choose from. (Because, as we've found, some players are as stumped at 'Make something up!' as we are frustrated about 'These are your 3 flavors. Only 3.') So we've instead focused on a 'formulaic' approach, basically multiplying lists of stuff - x power source times y weapon equals z item, and using separate mechanics from semantics, sort of like Mutants and Masterminds.

Rant aside, my concern here is in getting 'inspiration' and themes from other games, (like D&D suppliments, Pathfinders, etc.) I don't want to copy too much. For 'uniqueness' purposes, but also for potential legal issues. At the same time, however, (a) these are known for being super inclusive, and I want to cover the 'traditional' themes as well as encouraging original themes.

If I'm overly concerned about 'copying' then traditional settings like Steampunk/Alchemy or Modern tech end up with some pretty identical lists. I am looking through lists to gather 'themes' I can use, not too worried about that. Where it gets dicey for me is when I like a specific metallurgical Alchemy component, for example, I can tweak and rename, but what if I want 10 from the same list? How many is too many?

And we know that at least some players will want to make a completely 'inspired' cough #unoriginal# character like a Jedi or a HP Wizard or a Power Ranger. * Shudder * I have no interest in releasing an extension for something like that, of course... But I wonder if even a tweaked version would be an issue. Though we did joke about releasing a My Little Pony setting.

Any thoughts, examples, feedback, or gems of wisdom you can offer on the subject?

Thanks, friend.

Answer 1

I am, as usual and last I checked, not a lawyer. What follows isn't legal advice from a legal professional, it's layman knowledge gleaned over a couple decades of engagement with the practical impacts and relevance of intellectual property on citizens of North America as publishers and consumers of media. If you're concerned that your actions might provoke a Cease & Desist letter or need to be defended in court, engage a lawyer for advice before proceeding with those actions.

This answer is also tuned to the fact that you are in the United States.

General ideas can't be copyrighted, so borrowing ideas is not going to cause trouble. Borrowing specific named items can even be fine—the original D&D borrowed mithral/mithril wholesale from Tolkien's novels about Middle-earth, including the name and function, since the name is not a trademark and the idea is not something the Tolkien Estate can own and prevent others from using. (The situation is different when taking story elements though, such as places and characters: those are usually considered impossible to divorce from their original source, making them subject to copyright protection. The difference is subtle but an established precedent legally.)

When renaming things, it gets even farther into the clear: if you like the idea of Cormyran duskmantle leather as a crafting material that you read about in a game supplement, borrowing its (non-mechanical) use and function and calling it swiftleather is not going to be a problem.

Even things that are recognisable aren't issues: you can totally have a character type option that loudly emulates Drizzt Do'Urden without using that name, and everyone will get the reference—but the idea of a wilderness warrior form an ostracised race fighting with two curved swords is not copyrightable. (Of course, borrowing the character itself is a problem: if you have a pregen of that character type option named Trizzd who is a dusk elf who left Marzipanbarrens and forged a friendship with the Woman of Shinymoon, then you're on thin ice even if you're going to argue it's satire; if you have a pregen named Drizzt who comes from Menzoberranzan and is friends with Bruenor Battlehammer then that's copying the character itself and a no-go.)

For a practical example, check out Epyllion: it's basically My Little Pony except with dragons. Nowhere does it copy from MLP, but the inspiration is clear to anyone who is familiar with the show. It's even set in Dragonia and the major theme of the game is the power of friendship. As ideas go, MLP is a very clear inspiration, but it doesn't rip off the places, characters, and names of MLP—instead it took the themes and structures of MLP, drew from other ideas (original and from other inspirations) and made a new thing to express the same kinds of ideas.

In general, ideas aren't owned by anyone, just the actual work that people put those ideas to. If person A includes a red metal that floats in water in their game, the owners of Glorantha don't have any grounds to go after them for it, even if they can prove that person A has read about Gloranthan metals. What people are given temporary monopoly ownership over is what they actual create around the ideas: the actual media they produce based on the idea.

If it were otherwise, the entire project of having a culture would be impossible. Imagine if there could only be one cop show, one superhero movie, one book about alien contact, one painting of sunflowers. The world would be a very different place if copyright covered ideas, not just the words and pictures used to express ideas.

So yes, you can take inspiration for things from all over. You can have character classes that are homages to character ideas from elsewhere as long as you're not re-using their work, only referencing their ideas. You can have materials that are references to other games, so long as you're not just collecting together everything unchanged. Make it an original composition, not just copying, with an original expression and value, and you'll be doing what everyone else has been doing since the second RPG was invented after being inspired by the first.