This post makes a case for a “hodge-podge” (a.k.a. heterogeneous, incoherent) design on the basis that different genres demand different mechanics and crucially

Games which typically spawn the longest-running campaigns embrace the largest variety of genres and subgenres (to keep the game interesting over time).

While I think there’s some tenuous logic here (what’s typical? How broad is the sample set? Who observed this?) it chimes in with something I already had in draft. So, here is my case for why a heterogeneous, incoherent hodgepodge might actually be better than a unified mechanic, both for learning and for play.

One: Chaos

Here Tim Harford talks about mess and creativity


Chaos, mess and sub-optimal conditions makes for creativity. And in related news procrastination makes us more productive according to Professor Adam Grant.

So the argument here is that a heterogeneous system that defies expectations is more challenging and stimulating. That might suggest that your heterogeneous design works better as a learning tool, and provides more variety in the long term. However the design relies on getting better results through uncomfortable or stressful (even adversarial) situations. Whether you can dial that back (so the players don’t revolt and leave) and still make for a varied challenge is something to be tested. Need more data.

Two: Working Memory and Chunking

The other hypothesis is to do with working memory. For Knowledge Management and Cognitive Tasks we like to throw around the Magical Number 7, i.e. the number of objects in working memory being 7 +/- 2. These are the disparate elements in your game design, which together make your holistic view of your complete system.

Well then, you think: obviously your one, unified mechanic represents a less complex system than seven disparate ones. A unified system is still better.

But it’s not that, for a couple of reasons. One, for the average player, it probably makes little difference to them whether they’re looking at seven objects or just one; the cognitive burden is similar.

Two, the emphasis with heterogeneous systems is on elements that look and feel different, and that disparity could actually aid recall, perhaps by a chunking mechanism. And this also leads to your unified mechanic’s weakness: everything looks the same. A single mechanic isn’t just a single mechanic, it’s a starting point with an unbounded number of usage cases. This is arguably more complex than seven disparate objects with clear boundaries.

Consider a game where the only mechanic is a percentile skill list of 200 skills. Simple to grasp, but near impossible for the average player to get an holistic view. This is compounded when

  • every skill looks the same but has wildly different context and even power levels (e.g. Vampire’s skills, attributes and disciplines are rated on the same scale), and
  • when designers split up their list into four or more smaller lists (listen to the Gauntlet podcast moan about Night’s Black Agents here)

Now maybe your heterogeneous design may have more than 9 parts. If they’re all in play at the same time, you will have a problem with cognitive burden. But if you just swap conditions in and out of play (circumstantial mechanics, custom tables, things to interact with on the table) the holistic view of the game can be preserved. My further theory is granting the players this holistic view may have a positive influence on player satisfaction, although I have a strong bias here because that’s what increases my satisfaction. But you can have a system of “core” and “transient” modules that, at any one time make up your 7 +/- 2 pieces that the players call “the game”.


The social media debate around whether unified or disparate mechanics are better for long term isn’t high value; it’s supposition or based on anecdote. Resolving this means you need to be able to measure

  • player satisfaction and engagement
  • how much the GM sticks to, or deviates (hand waves) from their unified system (as a control)
  • the number of disparate elements, i.e. does my theory that 7 +/- 2 disparate elements produce no more cognitive overhead than just one?

and apply this to several groups running both unified and heterogeneous systems.

(when there’s time left over, you can also test the idea that most long-running campaigns need someone for the other players to look down on)