Invisible Rules in Games

Not too long ago I participated in a discussion among some game designers where the question was, basically, "how many of your rules can be left unwritten?"

This is an interesting question, because it has a whole lot of unwritten questions built into it (so meta). There's one big question that I didn't think of at the time, but occurred to me later while working on one of my own games:

Are we talking about things we assume the player will automatically know, or things that are technically true, but knowing it won't help the user play the game?

When we make this distinction, we recognize that there are actually 2 broad categories of "invisible" rules:

  • Things that are true, but do not help the player learn: Over time, a designer will learn certain things about their game. This will inform their design, but the player does not need to know them in order to play the game. We'll call these Design Rules.
  • Things we assume the player knows: Most people, even non-gamers, have some knowledge of how tabletop games work. For example, most people will tend to think of a discard pile as being a face-up thing in the middle of the table. Let's call these Intuitive Rules.

Design Rules

In one of my games – the trick-taking game that got me thinking about this distinction – you play 2 cards at a time: one for its number, and one for its effect. All cards have both a number and an effect, and deciding when to use a card for one or the other is part of what makes the game interesting.

Over time I learned that, due to the nature of the game, the effects cannot be self-contained. They must always impact the number card in some way. Whenever I made a card effect that worked or didn't work regardless of the number card, it led to boring decisions or effects that felt useless. Based on this, it is now a rule of the game that all effects must interact with the number card in some way.

Even earlier, I found another rule. Since all cards have both a number and an effect, the low-number effects must work well when paired with high-number cards, and the high-number effects must pair well with low-number cards. This ensures that all cards feel useful for both their value and their effect. Whenever I failed to do this, I ended up with cards that felt like duds.

Importantly, neither of these rules are essential or helpful for a player either when learning the game, or even during normal play.

In fact, telling these things to the player risks smacking them with information overload.

Generally, we shouldn't tell the players about design rules. Instead, through repeated gameplay, the player may naturally learn some of the design rules themselves as they start to notice patterns. Or maybe they won't. It's up to them how much or how little they want to grok the game.

There are some exceptions, where we need to write design rules in the rulebook. For example, how many cards are in the deck? How many suits? What card values are possible? A player is perfectly capable of playing without know the answer to these, but these are useful to create meaningful decisions in the game. If the player doesn't know whether an 8 is high or not, how can they be expected to decide the best time to play it?

Intuitive Rules

There is a subtle balance when thinking about including rules that we think might be intuitive. Having a shorter rulebook makes for an easier read, but omitting certain rules might make the game harder to learn or teach.

A good example of an intuitive rule can be found in Port Royal, designed by Alexander Pfister. It makes no mention at all of a discard pile in the rules, however it very frequently mentions discarding cards. So, is the discard pile face-up or face-down? Is there one central discard pile, or does each player have their own? Is there even a discard pile? But we really don't need answers to these questions; people intuitively put their discards in a face-up pile somewhere within reach of all players.

By omitting details about the discard pile, we let players fill in the gaps, and as a result we have a shorter, easier-to-follow rulebook.

But we need to be careful when thinking about what rules are intuitive enough to be omitted. Sometimes, a rule can feel intuitive to the designer when it is not intuitive to a player.

Another game by Alexander Pfister, Great Western Trail, is notoriously hard to teach. I think the reason why is because of something that I can easily see as feeling intuitive to the designer and publisher, but it is not at all intuitive to the player.

That is, GWT is actually a deck building and hand management game. But there are enough other systems in the game, that are all given equal weight in the rulebook, where that fact becomes obfuscated. The game also doesn't feel like a deck builder, because you are moving a character around on a board and building buildings and hiring workers and operating a train. Those mechanisms all send signals that are dissonant with the idea of a deck builder.

This may be stretching what one might call a "rule," but I think it still applies, because it's still something that should have been included in the rulebook. All the "rules" about how the deck works and how to interact with it are technically there, but with complex games it can be hard to see the big picture until you're halfway through your first game, and by then it's too late, your first impression has been made.

A simple note would have been effective, calling out concepts a player should consider when managing their deck and their hand. But because that note is absent, and because the other mechanisms all lead players away from the idea that this is a deck builder, players fail to think about it that way, so the game becomes hard learn and hard to teach.

Final Thoughts

We've discussed two kinds of rules you might consider as candidates to be invisible, i.e., not included in the rulebook:

  • Design rules should almost always be invisible. The exception is when a design rule helps you make better decisions, for example the range of values you have in your deck of cards.
  • Intuitive rules might be candidates for making invisible, but be careful that the rule doesn't just feel intuitive to you because you are the designer or publisher.

In the end, the decision of what rules to keep invisible is an important one and there is no one-size-fits-all approach. But by breaking them down into these two categories, hopefully you'll be better equipped to make the best decision for your game.