I've been tinkering with a design for a while, looking at other games for inspiration. The core mechanic from Savage Worlds fits my design goals perfectly, but I'm thinking of changing much of the rest of it. I've tried coming up with an original mechanic, but nothing I've tried attains the simplicity of the SW mechanic. What are the ethical implications of "stealing" a game mechanic?

I understand for my own use I can do what ever I want with a game's rules, and though I may not publish anything, I was thinking of posting rules on a website for free download. I want to make sure I"m not stepping on any toes or breaking any copyright laws.

In an effort to avoid stepping on anyone's toes, I've occasionally found myself going to extreme lengths to make sure that some mechanical element of my systems isn't too similar to someone else's work. Too often, this ends up in unnecessarily convoluted systems that lose touch with their design goals. The way I see it is this, if you absolutely must use someone else's mechanic, at least give them due credit. Everyone likes praise.

There's an oft-quoted bit of lore around RPG design that says you can't copyright the actual mechanics; how to roll dice, how to add the figures, whatever. You can copyright the tables you use to explain it, the specific block of text you use, et cetera, but not the actual, nuts and bolts; it'd be like someone copyrighting the equation 3 + 3 = 6.

However, as I have never myself looked into this, and the laws may or may not be different wherever you live, always check with someone lawyer-like first before jumping into the fire.

That in mind..

Use the mechanic. Do like Daniel says, give credit; say, "I wanted to come up with something original, but this is, quite honestly, the best thing for us to use. Person A is a genius, and I'm glad he wrote this. It's just great." Or something to that effect.

Legally, unless the process itself is trademarked somehow (as WotC has done with a few things), it's impossible to "own" a mechanic. There are countless instances of multiple designers coming up with the same mechanic simultaneously. You can't legally use their *description* of a mechanic, without permission, but as long as you describe the process with you're own words, you should be fine, even if you publish commercially. Especially if you give credit (i.e., "these mechanics were based on..." or "these mechanics were inspired by...")

Of course, there's also the flip side that, if you're dealing with a big company, it doesn't really matter what the law is, because they will fight a losing court battle to beat you down with lawyer fees.