Zendo (game)

Zendo

The beginning of a game of Zendo. According to the marker stones, the koan on the left follows the Master's rule, but the one on the right does not.
Designer(s)	Kory Heath
Publisher(s)	Looney Labs
Players	3–6
Age range	All ages
Setup time	< 5 minutes
Playing time	5–30 minutes
Random chance	Low
Skill(s) required	Inductive reasoning Pattern recognition

Zendo is a game of inductive logic designed by Kory Heath in which one player (the "Master") creates a rule for structures ("koans") to follow, and the other players (the "Students") try to discover it by building and studying various koans which follow or break the rule. The first student to correctly state the rule wins.

The game can be played with any set of colorful playing pieces, and has been sold with a set of 60 Icehouse pieces in red, yellow, green, and blue, 60 glass stones and a small deck of cards containing simple rules for beginners. Origami pyramids are a common choice of playing piece.

The rules were published in 2001 after more than a year of playtests and changes. A boxed set of the game was released by Looney Labs at the 2003 Origins Game Fair but is now out of print. Zendo is also published in Looney Labs' Playing with Pyramids, a book of rules and strategies for a dozen popular games playable with Icehouse pieces.

Zendo can be compared to the card game Eleusis and the chess variant Penultima in which players attempt to discover inductively a secret rule thought of by one or more players (called "God" or "Nature" in Eleusis and "Spectators" in Penultima) who declare plays legal or illegal on the basis of their rules.

Within Zendo, most players are known as Students, who will build structures of pieces known as koans. Before play, one player (known as the Master) will invent a secret Rule, such as "a koan has the Buddha-nature if and only if it contains one or more green pieces". The Master then builds two koans - one which follows the rule and one which does not. These are marked with a white and black stone respectively.

Students then take turns to build koans. After building a koan, a student may call either "Master" or "Mondo":

At the end of their turn, a Student may spend Guessing Stones to guess the Master's Rule. If the guess is wrong, the Master may build and mark a new koan (which either fits the Master's Rule but not the Student's guess, or vice versa) to prove this. The first student to correctly state the rule wins that round and becomes the new Master.