I'm Morgan McGuire (@CasualEffects). I've been working on computer graphics and games for 20 years at great places including NVIDIA, Williams College, Brown University, and Activision.

See my home page for a full index of my blog posts, books, research, and projects.

Sunday, July 27, 2014

McGuire House Rules for Settlers of Catan

The Settlers of Catan is perhaps the most widely-played modern board game, easy to learn, deep
enough to be interesting for everyone, and playable by anyone old enough to add small numbers. The game was designed by Klaus Teuber and first published in 1995 by Kosmos and other companies. It has since been revised and expanded many times.

The basic gameplay is similar to Monopoly: players gain resources through random events, build small and large buildings to increase their income, and trade resources.  Unlike Monopoly, Settlers grants players significant control over the randomness, expands from a single resource to a five-commodity economy, separates points from resources, and keeps all players in the game until the end (which usually arrives after about 45 minutes). These elements are the hallmarks of Eurogames and were popularized by Settlers, which initiated the current board game Renaissance.

The base game has several drawbacks, which were oddly compounded instead of reduced by the published expansions (for example: Knights & Cities and Seafarers). Settlers is poorly balanced compared to more recent games for two reasons.

First, the setup round in which players choose their starting positions largely determines the game. This is because an experienced player will seize resources that allow him or her to more quickly enter the positive feedback loop of expansion ("building an engine").

Second, there is too much variance (colloquially, "randomness") in the resource model and equally-matched players will have very different scores. Part of the strategy is naturally to minimize the impact of variance by diversifying one's resource pool, but the underlying spread is too high to overcome through strategy. For these reasons, many players quickly graduate to Puerto Rico and then Agricola, which have a similar feel but more strategic and focused play.

In the McGuire household, we've adopted several modifications of Settlers of Catan that keep it engaging and challenging for more sophisticated players while also making it more fun for young children.

We find that these rules work well for our diverse mix: a seven-year old and peers, some hardcore board gamers, and visiting college students and older adults who haven't played Eurogames before. I describe these rules relative to the American 4th edition printing.

An overview of our changes and motivation for them are:

  • Eliminate the imbalance of placing first or being very experienced during the setup round (see also Carian's game-theory inspired Last Diminisher opening)
  • Give weaker players a head start
  • Speed up the opening of the game, when no-one can do much in the base game because there are few resources in play
  • Eliminate the need for card counting, which is tedious and too hard for young players
  • Eliminate "attack" moves (robber, knight, and monopoly), which force an undesirable choice between group harmony/happy marriage/smiling children and effective moves
  • Ensure that everyone has an equal number of turns to build
  • Ensure that the current player receives a resource when rolling a 7; this is the most common number in the game and in the base version often results in no income, slowing down the game


1. Construct the frame for the island and set aside the desert hexagon. Shuffle the remaining resource hexagons and then stack them face down. Place the resources within the frame to fill the island, leaving one space along the border blank. The choice of space will affect the available ports and could be chosen randomly, but in practice this doesn't matter much.

2. Place the desert hexagon face down (so that the sea background is up) in the remaining space...it is now the harbor. Take the extra port tile corresponding to the port that was lost in making the harbor, and a 3:1 port tile, and place them on inner corners within the harbor.

3. Sort the round letter tiles alphabetically and place them in a tightening spiral from the outer hexagon adjacent to the harbor in towards the center, as in the game rules (the harbor is water and does not receive a letter tile).

4. One of the best players places two settlements (houses) and two roads for each player color, one adjacent to each house. Settlements are placed at corners where three hexagons meet (or on the outside of the island) and roads are placed along edges between hexagons. All settlements must be separated by two edges from each other. It is in this player's interest to make all colors equally good because this player is likely to be assigned the worst of these colors. It is generally a good idea to place settlements to obtain the highest sum of dots on adjacent hexagons, to be adjacent to every kind of resource, to cover as many different numbers as possible, and to leave room for expansion. 

5. Starting with the weakest player and proceeding in skill order up to the player who placed the initial settlements, each player chooses which color (settlement placement) that he or she would like. After all are chosen, players who care about the actual color (vs. the setup) may swap pieces to obtain their favorite color in the chosen position.

6. Each player receives the resource for each hex adjacent to his or her two settlements.

7. Give weaker players the additional resource cards of their choice. Our seven-year old currently receives eight resource cards.

8. Roll for who will play first.


Each player has a hand of resource cards that are maintained face up and organized so that others can easily see and count them, a set of (maybe zero) development cards that are face down, a set of played development cards that are face up, and a pile of settlements, cities, and roads that have not yet been deployed.

Players take turns in clockwise order around the table. Each player's turn has two phases: resource [distribution] and trading.

Resource Phase:
Roll 2d6. 

If you rolled a number other than seven, then all players receive resources according to their settlements (this is the same as the base game rule). For each settlement adjacent to a hexagon with the number rolled, a player receives one of that resource from the bank. For each city adjacent to a hexagon with the number rolled, a player receives two of that resource from the bank.

If you rolled a seven, then all players with more than seven resource cards in hand lose half of their cards (round down; if someone has nine cards, then he or she loses four). All players are immune to losing cards before their first build phase of the game. You receive a prize for rolling the seven: another player holds a shuffled hand of one of each resource from the bank and you blindly choose two resources from that. The remaining cards are returned to the bank.

If you like theme for your rules, then, on a seven: a tornado blows through the island, destroying some stockpiles but depositing a windfall for this player. Tornadoes are scary, so in my house we instead shout, "it's your birthday" when a player draws from the bank's hand, for reasons only clear to my children.

This phase must be resolved before any trading.

Trading Phase:
You may trade resources with the bank for other resources; for development cards; and for deployment of your cities, settlements, and roads. 

You may trade resources with other players for resources. The same kind of resources cannot be exchanged, and each player must receive at least one resource. You may not trade objects other than resources, including: development cards, buildings, and promises or "I Owe You"s.

Other players can only trade with the current player, although they may initiate multi-way trades using the current player as a middleman. Each trade must be completed before the next begins. For example, a player cannot use a port in the middle of a trade with another player.

During the trading phase, you may play one development card that was not purchased that turn. The development cards contain the rules on them, although we modify two of them. Victory Point cards are never played, but are revealed when the game ends. The modified rules are:

Knight: The knight card does not move the robber (since there is no robber in our game!) Instead, playing a knight allows you to draw two random cards from the bank, as if you had rolled a seven. This avoids having players attack one another. Knights still count towards largest army and in practice are typically deployed for the purpose of winning that award.

Monopoly: When declaring a monopoly, count the number of resource cards in all players' hands (including your own) of that resource type, and then receive that many of that resource from the bank. This avoids having players attack one another and accelerates the game instead of slowing it.

Victory Condition

A player must declare at the end of his or her turn if he or she has a total of 10 victory points (including development cards). The game then ends at the end of that round. That is, the game ends as soon as the original first player's turn begins, so that everyone has had an equal number of trade phases. All players who have at least 10 points at this point win.

This rule encourages ties and also ensures that everyone has had a fair number of turns. It slightly prefers earlier players who had a chance to trade before others knew that the game was ending, but it is unlikely that anyone would make a disadvantageous trade knowing that another player was likely about to end the game.

After the game ends, adjust starting bonuses for players for the next game. We find that if you want small children to play with you more than once, then it is a good idea to first overestimate their bonuses and then bring them back down until they win a proportional amount of the time.

Morgan McGuire (@morgan3d) is a professor of Computer Science at Williams College, visiting professor at NVIDIA Research, and a professional game developer. He is the author of the Graphics Codex, an essential reference for computer graphics now available in iOS and Web Editions.