Game mechanics are the operating system of your campaign. And like computer operating systems, they are built from thousands of lines of code that interact with one another in complex ways. Kit-bashing your system can be a lot of fun, but also a lot of work. And it can lead to unpredictable results or the need to improvise rules issues on the fly.

But not all rules are as closely tied to the overall system as others. In fact, sometimes even a signature rule or subsystem isn’t really wired tightly to the core mechanics at all. Call of Cthulhu’s sanity system can pretty much be lifted, lock, stock, and barrel, and used in just about any other game. Pathfinder with sanity? D&D? Hero system? Just plug it in. You don’t really need to bring anything else over from CoC, and you don’t need to add anything new to the core of the recipient’s rules.

I’m a big fan of taking great ideas from any source I can get them to improve my campaigns and GMing technique. So here are three rules sets that can make your game better today, with little or no kitbashing required.

GUMSHOE’s clue system: I’m playing a Trail of Cthulhu campaign now, and it’s pretty damn cool. One of the signature innovations of GUMSHOE, the game system under Trail of Cthulhu, is the idea that in an investigative campaign, finding clues should never be in question–it’s what you do with them that matters. If you go to a scene, and someone is so much as slightly trained in the relevant skill, and you look for the clue, then you get it.

This isn’t even a mechanic, per se. It’s really more of a philosophy, a GMing style, which makes it particularly easy to steal for your own campaign. That said, in GUMSHOE there are mechanics for finding extra, or more detailed, clues. So to make the most of this you’ll want to think about how you implement clues in your game.

If a Gather Information check at the seedy bar would have been the means for finding the pirates’ secret lair, that info is now “free” to the characters if they go into the bar looking for it. The successful Gather Information check (perhaps with a more challenging DC) also tells the heroes how many pirates to expect there, or their next target, or the secret entrance to the lair, or whatever. You’ll want to rethink your adventure design, so that the key clues necessary for moving the story forward are always destined to be found–but the information that makes things easier, or more interesting, or that unlocks cool subplots, still lurks behind the game’s mechanics and the players’ use of them.

D&D 4th Edition’s bloodied status: I was first introduced to the idea of a “bloodied” creature two years before the launch of 4th edition, when Rob Heinsoo and James Wyatt pitched the first concept draft of 4th’s (then code-named “Orcus”) core mechanics to the rest of R&D and the Brand team. I’ve used it in every game I’ve run since.

At its core, “bloodied” just means “has lost half its hit points” (or whatever measure of vitality your game uses). As such, if nothing else it makes a nice shorthand for that “it looks like it’s starting to get pretty badly hurt” line that every GM says on occasion. Adopting the concept will improve your game just with that use.

But you can also easily hang specific effects off the “bloodied” descriptor. Cowardly creatures (perhaps the word “sensible” is more realistic) might flee when bloodied. Ferocious ones might gain a +1 bonus on attacks. Bloodthirsty ones might focus all their attacks on bloodied characters. Creatures with limited-use resources (a drama point, or a single-use weapon) might be most likely to use them when they become bloodied. Groups might change tactics when their leader becomes bloodied. Et cetera.

And if you feel like kit-bashing, the “bloodied” state is a great trigger for specific bonuses, penalties, or powers. It’s pretty easy to implement without getting too tangled up in your game’s existing mechanics. Give that creature some unexpected ability–or weakness–that only shows up when bloodied.

Numenera’s XP: In Numenera, you gain an XP point if you make an interesting discovery, meet a goal of the adventure, or accept a GM intrusion (an unexpected complicating factor the GM tosses in to throw you off balance). You can spend these points to improve rolls or advance your character. The GM intrusion concept is a pretty cool twist, but the rest of it isn’t new–the Deadlands experience system worked almost identically 20 years ago, and I’m pretty sure its ideas spun out of TORG and a couple of other games around at that time.

There are two components to this one: A system for advancing characters, and a system for granting bennies for clever or challenging play. The first is a bit tricky–you need an algorithm for advancing characters with XP points instead of your game’s native system. But you can skip that if you like.

You’ll get a lot of mileage out of just rewarding your players for accepting your plot twists, coming up with exceptional ideas, or even (as we often did back in my Deadlands days) just making the group laugh. Giving people the odd re-roll is a small price to pay for this improvement to your game. For best results, use some sort of physical token (Numenera uses cards; Deadlands used poker chips) to represent the points; it will make them feel like a sort of currency.

These are three subsystems I’ve ripped out of other games to use in virtually every campaign I run, in virtually any system. I’m sure there are plenty of others that could be lifted just as easily. What are your suggestions?

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