TwixT

TwixT is a two-player strategy board game, an early entrant in the 1960s 3M bookshelf game series. It became one of the most popular and enduring games in the series. It is a connection game where players alternate turns placing pegs and links on a pegboard in an attempt to link their opposite sides. While TwixT itself is simple, the game also requires strategy, so young children can play it, but it also appeals to adults. The game has been discontinued except in Germany and Japan.

History

TwixT was invented as a paper and pencil game in 1957 by

• The players take turns placing pegs of their respective colors on the board, one peg per turn.
• The player with the lighter color makes the first move.
• A player may not place a peg on their opponent's border rows.
• To counteract first-move advantage, the pie rule is suggested. After the first peg is placed, the second player has the option to swap sides. This is typically indicated by turning the pieces box end for end, or swapping boxes if they are separate. If the second player chooses not to swap immediately after the first peg is placed, then sides may not be swapped later in that game. (This "one-move equalization" was added by Randolph after 3M published his game. It is present in the Schmidt Spiele edition and all later editions.)
• After placing a peg, a player may link one or more pairs of pegs on the board of their colour. The links can only connect two pegs a
  pencil and paper
  play allows a connection to cross the player's links but not those of the opponent.
• The object is to make a continuous chain of linked pegs connecting the player's border rows. If neither player can achieve this, the game is a draw.

Computational complexity for general rectangular boards

TwixT has been proven to be

One variant is Twixt PP (Paper and Pencil). The rules are almost identical to standard TwixT, except links are never removed and a player's own links are allowed to cross each other. A winning path might loop across itself but crossed links are not connected to each other at the intersection. The paper and pencil rules may reduce the number of draws (which are already rare). Whether it reduces the complexity of the game or not is highly debatable.

This rules difference has no effect in terms of game outcome most of the time. For those rare situations where it does, most of those cases are where a draw under standard rules is a decisive game under PP rules. The image shows a contrived position where black is to move. Black wins under PP rules but loses under standard rules.

Row handicapping can be used to equalize the game for players of different strengths. The simplest handicap is to allow the weaker player to move first (i.e. eliminate the pie rule). Beyond that, one dimension of the grid is reduced so the weaker player has a shorter distance to span.

The game may be played on different size grids. The 12×12 board shown here leads to a very short game. On the standard board, tactics dominate; larger boards introduce deeper strategic considerations. Since most commercial sets use boards which are made from four "quadrants" which either clip together or are hinged, a 36×36 grid could be assembled from three standard sets of the same size. In Europe, there briefly appeared a TwixT knock-off called "Imuri" which used a 30×30 grid. The board had no holes, and lines were drawn to indicate where the links could be placed. This edition was removed from shelves for copyright infringement.

Mark Thompson's variant Diagonal TwixT has the same rules as standard TwixT, but the border lines run at a 45-degree angle to the grid.^[5] David Bush's version has the border lines running parallel to link paths. These variants result in different tactical patterns.

Competition

The official world championships were held as part of the Mind Sports Olympiad in 1997, 1998 and 1999.^[6] Since 2000 TwixT has had a major international tournament as part of the MSO but there has been no official World Championships. Between 2011 and 2022, the TwixT event at the MSO has again become the World Championships. The list of winners is given below.^[7]

List of MSO champions

Reception

• Jeux & Stratégie #6^[11]
• Games & Puzzles #18^[12]
• The Playboy Winner's Guide to Board Games^[13]
• Family Games: The 100 Best^[14]

See also

• List of connection games
• Gale, also called Bridg-It

References