Expansions Dilute Base Game Content

One of Carcassonne's greatest strengths is its rich array of expansions. Expansions range from the push-your-luck shepherd to the dragon's take-that antics. It is tempting to dump all your expansions into the base game at once, but if you do, you'll run into two issues. First, because the game length depends on the number of tiles, it becomes way too long. Second, specific expansion content becomes hard to find.

Expansions are fun, but they dilute the base game content. Depending on what the expansion adds, this may or may not be an issue. When it adds content you select before play, such as new aliens in Cosmic Encounter, there is no problem. The problem arises when you dilute content, making certain things harder to find.

Some components are crucial. In Galaxy Trucker, players must have crew cabins or else their ships fail. Imagine we add 10 new expansions to Galaxy Trucker, and none of them include crew cabins. Finding the cabins becomes impossible or at least burdensome.

Many games solve this by limiting how much expansion content you can bring into a game. Railroad Tiles is strict in this regard: it only allows one expansion. Furthermore, it has rules for how it presents expansion tiles to players. Rather than mixing them in with the base game, you keep the tiles separate. You then populate market columns with a precise mix of tiles from both the base game and expansion pools. This ensures players always have opportunities to interact with both expansion and base-game mechanics.

A more casual approach to limiting content is to divide content into modules. You then tell players to use only a certain number of modules when creating the deck. Wiz-War uses this approach. Cards have schools such as Conjuring, Alchemy, or Mentalism. Before the game, you choose three schools, plus the cantrip cards, to include in the deck. This is especially clever because the base game already contains six different schools of magic. It gets players used to limiting their card pool before they even add in new schools from expansions.

The downside to limiting expansion content up front is setup and tear-down costs. Before each game, players need to create the deck, and after each game they need to separate the cards. Sometimes you want to throw everything into one pile and leave it that way. Spirit Island is a great example of this approach.

Spirit Island has two decks of power cards, one major and one minor. Expansions permanently add more cards to these decks. Cards have both unique text effects and combinations of elements. As you add more cards, specific text effects become harder to find. However, the game designs expansions to maintain the same balance of elements. No matter how many expansions you add, the chance of any specific element is the same. In fact, when the game removed powers for balance reasons, it replaced them with cards that used the same elements.

This works in Spirit Island because consistency comes from innate powers. Each player needs certain elements to unlock their innate abilities. It doesn't matter if you dilute text effects as long as players still have equal access to elements. As long as expansions maintain element frequencies, they don't dilute the game in any meaningful way.

Dilution depends on what your game is about. Some mechanics rely on drawing certain cards or tiles, and others don't care at all. When designing expansions, it is important to figure out which parts of the game are at risk of dilution.