Quadrature 1992

Quadrature, a 1993 Mensa Select, is a unique board game for two players. Each player has 18 men (flat cylinders), nine of which are initially situated on the third row closest to the player, leaving the edge columns empty. Each of the two “bars” in the center of the first and last rows consists of three distinct squares. The 121 squares of the board will be referred to as “locations.” Each player has a “marker” - a flat square token with one dot on one face and two dots on the opposite face. A player’s marker is the same color as his men.

There are two ways to win in Quadrature. One is to reduce the number of on-board, opposing men to two or less. The other is to advance three of your men into the bar in your furthest row.

Basic movesPlayers take turns making basic moves, one basic move per turn. You begin your turn by moving one of your men one location forward (away from you,) diagonally forward, or sideways to an unoccupied location. If you have no moves available, you must sit the game out until you do have a move available. Players are not allowed to pass on their turn. If neither player has a move available, the game is a draw. Sometimes, after a series of turns, a board position (arrangement of men of both colors) will be reproduced exactly. In such an instance, play immediately concludes as a draw.

SquaringIf you move to form a rectangle with horizontal and vertical sides (henceforth “rectangle”) defined by three of your men and one opposing man, you have “squared” the opposing man. At such time you must immediately initiate an “exchange” of the opposing man for one of your own while it is still your turn. You do so by placing one of your off-board men on top of the opposing man to be exchanged. Once you have initiated the exchange, your opponent removes his covered man from the board, at which time your turn is concluded.

If you move to square your opponent, and your subsequently added man squares yet another opposing man, you must immediately initiate an exchange of your opponent’s second squared man while it is still your turn. And so on. The number of exchanges per turn is limited only by the number of opposing men on the board. Once you have initiated all such exchanges, your opponent removes all of his covered men from the board, at which time your turn is concluded.

You are not allowed to move a man to a location which is squared by your opponent. That is, you cannot move to form a rectangle defined by your moved man and three opposing men. However, by way of exchange, you may add men onto locations which are squared by your opponent.

If, at the outset of your turn, opposing men are already squared by your men, you cannot begin your turn by exchanging said opposing men. You must begin your turn with a basic move, and you can only initiate exchanges on opposing men which were squared by your current move, or which were squared by men which you added to the board during your current turn.

MarkerIf you make a non-squaring, sideways move while your marker is not on the board, you must immediately place your marker somewhere on the board, single dot face up, while it is still your turn. If you make a non-squaring, sideways move while your marker is on the board with the single dot showing, you must flip your marker over to show two dots. If your marker is on the board with two dots showing, you cannot make a non-squaring, sideways move. If you make a forward, diagonally forward, or squaring, sideways move, you must remove your marker from the board.

Online Play

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