"So what is this game about?" is the natural first question you might ask when someone brings out a new board game for you to try. That question can have one of two answers, depending on the angle you look at the game from: theme or mechanics.
"The game spans 1500 years of Egyptian history. You goal is to influence Pharoahs, build monuments, farm on the Nile, and advance the culture of the people in an attempt to appease the god of the Sun."
"Okay, but what is the game about?"
"It is a set collecting and auction game. There is a wide variety of tiles that you'll collect, which combine in myriad ways to score points. On your turn, you'll decide whether to add one more tile to the pool, or to auction off the ones already there. Your goal is to collect those tiles which will be most valuable to you, prevent your opponents from getting too many tiles valuable to them."
Either of the above is a reasonable description of Reiner Knizia's "Ra". Since this is the Journal of Boardgame Design, I'm interested almost 100% in the latter. Either description could reasonably be called the game's "theme", but in practice "theme" has come to mean the historical context in which the game supposedly takes place. The designer drapes a bunch of mechanisms around the theme, and he has a game. Maybe the mechanisms are closely tied to the theme and often, in Eurogames, they aren't.
A game, at its best, is more than a bunch of mechanisms. It is a coherent system of mechanisms with a theme of its own. Let's call this theme that summarizes the system of mechanisms the game concept. There is nothing to prevent a game built from a bunch of connected mechanisms from being lots of fun, but I think that having a strong game concept takes the game up a level. It helps to focus the players' goals. It adds meaning to the game apart from the theme. It defines the game.
"Players choose among a series of actions which help them to score points, gain resources, or avoid catastrophes. The more you are able to take the same action during the game, the more valuable it becomes. The trick is that in each turn, a player is presented with three possible actions, and he must decide which one to play, and which ones to make available to the players to his left."
I enjoy explaining game rules, and I always introduce the game by first describing the game concept. Every rule has a role in supporting the game concept. If players can wrap the whole idea of the game around their heads, then all the individual rules ought make sense. Players can sit down and get to work at trying to win. If they can't get the game concept, then most likely you'll see the "deer in the headlights" look. "Okay, you explained the game to me but... what am I supposed to do?"
The issue of game concept surfaced when I recently first played "Amyitis" by Cyril Demaegd. On any given turn, a player will take one of five different actions. The Merchant and Peasant each give you distinct types of resources. The Engineer gives you immediate points and a shot at a majority battle, for more points, on the main part of the board. The Priest lets you take part in a different majority battle in a small part of the board, which help you win more points or resources depending on where you choose to play. Finally you may move the caravan - in which you spend the resources you earned elsewhere to earn: points from cards, income, faster caravan movement, or the ability to earn points on the main board, which in turn is limited by choices made by players who chose the Engineer earlier in the game.
So the game Amyitis is about... I'm not sure.
Cyril Demaegd has a defense of the structure of Amyitis which is worth reading. He described it as having a "star structure" rather than a "line structure". I think I understand his point. Some games, ones with a linear structure, have their elements lined up like dominoes. The first one effects the next one, and so on down, until the last mechanism which affects the victory conditions. "Power Grid" by Friedmann Friese is an example of this. You buy power plants, which give you capacity to use fuel. You buy fuel that fills your plants, and together they can power your cities. You extend your network of cities, which when powered give you victory points, as well as income that feeds the entire cycle for the next game turn.
What I think is meant by a "star structure" might correspond to what Americans call a "wagon wheel" or "hub and spoke" structure. There is a core mechanism and several secondary mechanisms. The secondary mechanisms may be independent, but they all affect the core mechanism.
The problem is that there is no core mechanism in Amyitis. The garden, which does take up the most physical space on the game board, really turns out to be just another way of scoring points that is not obviously more important than any other. Here's my picture of the Amyitis structure, which looks more like the floor plan from a spy movie than a wagon wheel.
From all this, it may come as a surprise when I say that I think Amyitis is a hell of a lot of fun. There are some very clever mechanisms in the game, and notwithstanding the nightmare diagram above, the interrelationships play well. However, playing Amyitis is a little like playing with sand. It can be lots of fun, but there is nothing to hold on to. A strong game concept doesn't make a game good. It makes a good game more substantial and more satisfying, and it serves a similar role that a good theme does.
Sometimes having one strong central mechanism that ties the others together can provide a game concept. The hub and spoke diagram above shows a game with many mechanisms which all affect a central one, which in turn provides the victory conditions.
"Caylus", by William Attia, does this, but works the other way as well. The central mechanism is the road, which players build upon and which provides the actions players must choose from. The road is also where the "provost" moves, and he can wipe out some players' actions depending on where they lie on the road.
"Players take actions on the road which gives them commodities, and then they use those commodities to create more buildings on the road (as well as the castle) to earn victory points." That's the whole game summed up in 32 words. Unless you're writing copy for the game box, being able to sum up a game in 32 words or less is no particular virtue. However, it shows that the game is well focused, with a strong game concept that ultimately ties together many mechanisms into a cohesive game. Players sit down to a game of Caylus with a strong sense of what they are doing, purely in terms of the game's mechanics.
A game can seem more complicated than it is when its game concept is weak. Many people regard Reiner Knizia's "Stephensons Rocket" as a complex game in spite of the fact that its rules are remarkably compact. Its rail building theme is pretty good - but what exactly are you trying to do with those railroads? You want to control them of course. But that only pays off at the end. Meanwhile, you want to run them in to cities, but only after you build stations that you ran the railroads into first. You also want to control the cities that you run the railroads into, and you want to control the commodities that each city produces. Finally, you want to merge the railroads in a way that insures you control the really big railroads at the end of the game. Whew.
In a public appearance, Reiner Knizia once said that scoring and victory conditions are good things to manipulate to get the players to do what you want. In the case of Stephensons Rocket, he took his own advice too well. He made the game work by tinkering with the scoring mechanisms at the cost of maintaining a strong game concept. The final product is a good game, but at times it seems to be a runaway train that is in constant danger of running off its rails.
Conversely, even a complex game can be held together with a combination of strong game concept and theme. Karl Heinz Schmiel's "Die Macher" holds together remarkably well despite being one of the most baroque of all German games. It takes about 45 minutes to teach the rules for Die Macher, and each turn has 13 phases. I don't think too many players would tolerate that sort of complexity if its mechanisms didn't tie so well to its election theme. When a theme is strong, the theme merges with the game concept. "Players represent political parties, each trying to get as many votes in regional elections as possible, which earns you points. You'll attempt to manipulate your party's policies and public opinion in order to get votes in those regional elections. Success in those elections in turn enables you to control the national agenda, which scores you more points." Along with Die Macher's strong theme, and the way it successfully bonds its mechanics to its theme, Die Macher has a strong central mechanism which gives it a strong game concept. Everything flows in and out of the regional elections. You manipulate policies, you buy media, you place party markers, and you manipulate your local popularity all in an effort to gain influence in the local elections. After you've scored your points there, the regional elections affect the national board which gives you money and points for the endgame scoring. Die Macher holds rather well to the spoke and hub model, with somes spokes pointing in to the hub, and others pointing out from it.
Die Macher benefits from both a strong theme and a reasonably central mechanism to maintain some conceptual unity. As games move along the spectrum from "Eurogame" to to "Simulation", the mechanics tend to blossom around the need to recreate reality rather than to maintain any conceptual unity. When a game is primarily a simulation, then the theme becomes the game concept. Imagine "Squad Leader" or "War of the Ring" as an abstract game and the rules would make no sense. Why create all these special exceptions and unique units? How can anyone possibly understand what is supposed to be going on? Once you realize that you are simulating small unit fighting or the battle for Middle Earth, everything comes together. The games remain complicated, but every mechanic serves the basic concept of the real world (or fantasy world) simulation. As long as the players understand what is being simulated, the mechanics hang together conceptually.
Games most often build their game concept around a central dominating mechanism which all others relate to. Are the other mechanisms truly secondary, or do they take on a life of their own? If those secondary mechanisms become significantly complex, the game can lose its focus. Compare Caylus with Age of Empires III by Glenn Drover. Both use a similar action selection mechanism, but Caylus is a more straightforward, focused game, while Age of Empires III adds a lot of extra stuff behind each possible selection and is a more baroque design.
In Caylus, actions taken on the road generally give a player resources or allow him to spend resources on a building. The entire game is about acquiring and spending resources effectively. There are other choices in the beginning of the road - and these create a little metagame around the use of the road: they control items such as turn order, the cost of an action, and which actions on the road will actually occur this turn.
In Age of Empires III one feels as though he is playing four games at once There is the entire colonization battle for majority control off on the side - but one need not participate in that game wholeheartedly. There is a separate module dealing with collecting trade goods. There is the "discovery" game which sets the stage for the colonization game, but has its own set of goals and victory points. Then there is the action selection game which determines how many resources you bring to bear in the other three games. These games-in-a-game all intersect and collide but without truly building upon each other. The theme of colonization just barely stitches this patchwork together.
"Puerto Rico" by Andreas Seyfarth may be the great enigma when it comes to the notion of game concept. There are many facets to the mechanics. Each one is essential and none seems to dominate. Is the game about the role selection? The selection of roles is a central and original concept, but I think it dominates the game much less than does the road and the selection of actions in Caylus. The specifics of the actions - which building to buy, where to put your colonists, your choice of plantations, trading and shipping - are all critical, balanced, and tightly woven. What is the game about? Well, it's an engine building game, of course, but it's about the whole package. To the new player, Puerto Rico is sort of a fascinating mess. To the experienced player, the game is its own concept.
Puerto Rico is relatively complex for a Eurogame, and it cannot be summarized by a simple game concept. Still, its structure is not especially convoluted as the diagram below shows. While all of its mechanics may be harder to describe than for Amyitis, the entire system is conceptually more compact. Compare the diagram for Puerto Rico, below, with the one above for Amyitis.
This diagram does simplify some things. There are ways of getting doubloons besides trading goods, and the various buildings can affect all of the game functions. However the basic engine is all there, and it makes for a pretty neat package. Puerto Rico's game concept may not be easily broken into its parts, but taken as a whole it is manageable.
This seems to be the nature of most "engine" based games. Games such as Puerto Rico, Power Grid, Goa, and Settlers of Catan cannot readily be understood in terms of their component mechanisms nor summarized by a central mechanism that drives all others. The cogs of each mechanism are too tightly meshed. The game concept is the total effect. The challenge is to create a structure that is complex enough to satisfy the designer's ambitions, but simple enough to be comprehensible. Anyone who has taught Puerto Rico to a newbie knows that even the simple structure pictured above starts to push the limits of comprehensibility for most people.
I think that this is the sort of structure that Cyril Damaegd had in mind when he spoke of a "line structure". Neither Power Grid nor Puerto Rico have structures which are simple lines, but both have a chain of causes and effects which takes place over several steps to yield victory points. Understanding the game requires understanding the chain.
When people ask "what is this game about?" they are most frequently asking about the theme. Unless the theme is well integrated with the mechanics - not a hallmark of many Eurogames - then knowing the theme doesn't really answer the question. For many of the best games - including ones with strong themes - a game is about its game concept. The game concept may be a strong central mechanism that the others all relate to, like the road in Caylus. It may be a dominant mechanism which virtually defines the entire game, like varied set collection rules of Ra. It may be the historical theme, as in a simulation game. It may be a tightly interwoven set of causal relationships as in Puerto Rico. Whatever it is, it brings the entire system together so that the player knows just what... the game is about. Without a game concept, what's inside the box can still be fun, but it may just be six mechanics in search of a game.