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

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

Sunday, July 20, 2014

McGuire House Rules for Carcassonne

Carcassonne is a family-friendly Eurogame (modern board game) that, with appropriate expansions and modifications, scales well from two to six players and admits serious competition at any age from five up. It allows players to chose a game length from about 20 minutes up to hours (with multiple sets). The game was designed by Klaus-Jürgen Wrede and was first published in 2000 by Rio Grande and others. This post describes our house rules for Carcassonne. For simplicity when learning the game, I give a nearly complete rulebook rather than differences from printed rules.

We've been playing Carcassonne for over a decade (most recently with small children). The McGuire house rules arose from that play experience, some in-depth game theory analysis, and analysis of rule differences in different regional editions and printings. We believe that compared to the American printed rules, these increase fairness and balance, extend the game to meaningful two-player play, manage game length, and increase strategy, while avoiding unnecessary complexity and staying true to the core mechanics that made Carcassonne great originally. I wrote an analysis of the original rules a few years ago for my game design course that explains the motivation for many of these changes.

For various reasons, including marketing and a desire to not reprint even when errors are discovered, the box that you buy of a game doesn't always have the best version of the rules. I encourage everyone to experiment with the rules of games that they play, and if you're playing Carcassonne, here are some to start with. Lots of folks will disagree with our rule set, and that's great too. The best part of playing a game is often changing the rules and finding where the lead you, and everyone has their own taste for what makes the game ideal.

Setup

We play a set that combines the base game with these expansions:
  • The River (ships with new editions of the base game)
  • Inns and Cathedrals
  • Traders and Builders
  • King & Scout
  • Six-player expansion
and a set of homemade 50-point markers, because games often run over 150 points per player and the scoring track only counts to 50. If you don't have all of these expansions, then you can just ignore some of our rules without affecting balance. We've tried and rejected The Count of Carcassonne, The Dragon, The Princess & The Dragon, and The Tower expansion, and some of the rules (but not the tiles) from the above expansions. The game has about 10 other recent expansions that we haven't tried yet.

If you lose some followers from your game set, you can purchase replacements ("meeple") and other shapes for your own new rules in compatible wood and colors from http://www.meeplesource.com/. I haven't found a good way to manufacture or replace tiles, however if you buy a second base game or some expansions you'll have an awful lot of tiles to work from and you don't need them all to play.

Decide how long of a game you wish to play. Choose a number of tiles equal to twice (or a bit fewer, if this is your first time) the number of minutes desired, rounded to an even multiple of the number of players.  Put all tiles in the draw bag. For a very long game, begin with the river tiles, otherwise, set them aside with the excess tiles. Even for a long game, always leave out a random set of a few tiles, and for all games ensure that no-one sees the tiles that are held back--this prevents "card counting" in the end game, which is slow, tedious, and an unfairly large advantage to experienced players.

Place the pigs on the zero square of the scoreboard  (if you don't have pigs from the base game, use colored counters).

Grant each player initial points based on his or her handicap. This should increase with the number of tiles in play. For example, my five-year old currently begins with points equal to 30 less than the number of tiles in the bag. After each game, adjust handicaps based on the final score so that each player begins the next game with a relatively fair chance of winning. We shift handicaps by about half the difference from the winner for children until stable, and more slowly for adults.

Put the first river tile or the start tile (it has a dark back) face up in the center of the table to begin the world. If you're using the river opening, follow the rules from the expansion for it--those are the only ones I don't repeat here.

Draw a three tiles and place these face up. These form the shared hand from which players will choose their tiles each turn. You may also wish to use a number of tiles equal to the number of player colors; that can slow the game down, but we've had equal success with it for balance and strategy.

Features

The cardboard squares are tiles. Each tile has one or more pieces of features on it. A feature is a contiguous shape that can span multiple tiles. A key concept is when a feature is complete and can be scored before the end of the game. The features are:
A Monastery 
  • Roads (white lines), which end at intersections with other roads and with cities. Bridges are not intersections. Inns and lakes are not intersections. Roads with inns on them have special scoring rules. Roads are complete when both ends are intersections with roads or cities.
  • Cities (brown areas containing buildings). Some cities contain blue-and-white checkered shields; each shield counts as an extra tile when scoring. City tiles entirely consumed by cathedrals have special scoring rules. Ignore the "trade good" icons. Cities are complete when their border walls have no gaps.
  • Monasteries (a.k.a. cloisters; centered large buildings surrounded by green) are single-tile features. They are complete when all spaces in the 3x3 grid centered on the monastery are filled.
  • Farms (green areas that may contain buildings) are bordered by roads and cities. Farms must be connected by a continuous green swath--where different cities pinch together at tile corners and no green passes through, a farm ends. Farms are never complete.
Four separate farms
There is a critical distinction in the game between separate features that are likely to merge in the future and continuous features. The primary strategic move in the game is claiming an unoccupied feature and then merging it into an occupied one.

Turn

A Builder
Players take turns in order around the table. On your turn, a take the following actions, in order:
  1. Draw a tile to fill the shared hand (on the very first turn of the entire game, the first player does not draw a tile) if there are any tiles left in the bag.
  2. Choose any one tile from the shared hand and place it in the world so that at least one edge is adjacent to another tile and all edges are consistent. (No corner-only touching, if there is a road or city, it must match up on all sides with any roads or cities present in the world.)
  3. Optionally do one of the following:
    1. Place one follower (little or big person) on the tile on a feature that is not already owned by anyone. By convention, farmers lie down in fields to make them clearer.
    2. Place the builder (looks like a chef) on the tile on a road or city feature that is already owned by you.
  4. Score any cities, roads, and monasteries that placing that tile completed, even if they aren't yours, and return those followers to the players who own them (see below). Note that scoring and retrieving followers and builders occurs after placing--if you didn't have a follower before closing a feature, you cannot recycle the follower that just returned home. Farms are not scored until the end of the game--farmers never return home.
  5. If you added your tile to a feature that already contained your builder, then optionally repeat steps 1 through 4 once. (You can never place more than two tiles in a turn.)
Play continues until all tiles have been played. At that point, commence end-game scoring.

(It may be possible to draw a shared hand that contains only unplayable tiles...although I have never encountered this in practice. I propose that if it happens to you, then you immediately declare the game a tie and go out for ice cream.)

Note that farms are features and a follower cannot be placed onto an already-owned farm. Builders cannot be placed onto farms.

In a two-player game, each player plays two colors and these colors are played in alternating order. For example: player 1 plays black, then player 2 plays red, then player 1 plays gray, then player 2 plays yellow. Each color is separate, as under normal rules (e.g., on red's turn, player 2 can't place a yellow follower), but the player's score at the end of the game is the sum of the scores of his or her colors. This makes sharing features viable in a two-player game--you just want to share more with yourself than with your opponent.

Scoring

During play (before the end of the game), a road, city, or monastery feature that is completed immediately scores points for the player(s) who own it and all followers and builders on that feature "return home" to the players who placed them. Farms are never completed.

A feature is owned by the player who has the most followers on it, with the large follower counting as two and the builder not counting at all. If multiple players are tied for most followers on the feature (which is a common and desirable case), then those players each receive full points for that feature. The values of completed features are:
Cathedrals increase risk and reward
  • Monastery: 9 points
  • Road:
    • With an Inn: 3 points/tile
    • Two tiles: 2 points
    • Otherwise: 2 points/tile
  • City: (recall that each shield counts as an additional tile)
    • With a Cathedral: 3 points/tile
    • Two tikes: 2 points
    • Otherwise: 2 points/tile
Note that the number of tiles is critical--if a city or road winds through the same tile twice, that tile is still only counted once.

At the end of the game, farms and incomplete features are scored as follows (score features, not followers, and remove them as scored to avoid miscounting):
  • Monastery: 1 point for each tile in the 3x3 grid centered on the monastery
  • Road:
    • With an Inn: 0 points
    • Otherwise: 1 point/tile
  • City: (recall that each shield counts as an additional tile)
    • With a Cathedral: 0 points
    • Otherwise: 1 point/tile
  • Farm:
    • 3 points/completed city touching the farm 
Note that multiple followers on a feature affect who owns it, but do not affect how many points it is worth.


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.