Three-player chess (also known as Three-handed, Three-man, or Three-way chess) is a family of chess variants specially designed for three players. Many variations of three-player chess have been devised. They usually use a non-standard board, for example, a hexagonal or three-sided board that connects the center cells (board "squares") in a special way. The three armies are differentiated usually by color.
Three-player chess variants (as well as other three-player games) are the hardest to design fairly, since the imbalance created when two players gang up against one is usually too great for the defending player to withstand. Some versions attempt to avoid this "petty diplomacy" problem by determining the victor as the player who first delivers checkmate (with the third player losing in addition to the checkmated player). Other solutions have been tried as well.
Hexagonal boards with quadrilateral cells
Some variants use a special hexagonal board with quadrilateral cells (see example in the photo):
- Trichess: features a "non-aggression" rule whereby a player in inferiority is immune from capture in his home portion by a numerically superior opponent, unless the capture also gives check. A pawn that reaches the back rank of an opponent is exchanged for any previously captured friendly piece. Played on a 96-cell board. By Chistophe Langronier (date unknown).
- ThreeChess: checkmate does not end the game—the first player to capture an enemy king wins. A player may not move into check. Played on a 96-cell board. By the ThreeChess Team (2010).
- Three-Man Chess: pawns reaching the 5th rank gain multi-direction capability. The first player to give checkmate wins. Played on a 96-cell board. By George Dekle Sr. (1984).
- Trio-Chess: played on a 96-cell board, a center triangle splits the central files. By Van der Laken and G. J. Buijtendorp (1979).
- Three-Player Chess: by Robert Zubrin (1971). Played on a 96-cell board. The patent for this game provides suggested rules whereby kings are captured, and the player with the last-remaining king wins. The pieces of an eliminated player remain on the board and may be captured. A player may move into check. The patent also describes a variant whereby the army of an eliminated player is appropriated by the capturer.
- Self's Three-Handed Chess: played on a 144-cell board. By Hency J. Self (1895).
- Waidder's Three-Handed Chess: played on a 126-cell board. By S. Waidder (1837).
Other boards with quadrilateral cells
Some variants have used other board forms with quadrilateral cells:
- III-Color-Schach: uses a special three-dimensional board or can be used with three-colored boards.
- Chess for three: by Jacek Filek (1992).
- Megachess: uses a roughly triangular board with 130 squares. Pawns have multi-direction capability. Players manage the first-mated player's army according to one of three options. The last surviving player wins. By Mega Games/Danny McWilliams (1986).
- Mad Threeparty Chess: play starts on an empty 10×10 board with players placing their pieces initially, including an extra king per side. Kings are designated so that each opponent attacks a different king of a given player. By V. R. Parton (1970).
- Triple Chess: uses a chessboard unbalanced by 8×3 extensions on three sides. A player must checkmate or stalemate both opponents to win, using only pieces of his color. By Philip Marinelli (1722).
Boards with hexagonal cells
Some variants use a board with hexagonal cells. Usually three bishops per side are included, to cover all cells of the hex playing field. Pieces move usually as in one of the versions of hexagonal chess:
- Chesh: played on a 169-cell regular hexagon board. By D. R. Hofstadter (2005); interpreted by Gianluca Moro.
- Chexs: by Stephen P. Kennedy.
- Echexs: by Jean-Louis Cazaux.
- HEXChess: commercial chess variant by HEXchess Inc.
- Three-Way Chess: by Richard Harshman, played by three players on a hexagonal board.
Boards with triangular cells
- Ch3Xs: a variant using a hexagonal board with 96 triangular cells created by Randy Ruether. Moves are based on standard chess but adapted to the triangular geometry.
- Chess for three: a variant using a hexagonal board with 150 triangular cells was patented in Russia by Ilshat Tagiev in 2008. Each player controls a standard set of pieces plus two extra pawns. Movements are similar to standard chess, except pawns.
Using fairy pieces
- Orwell Chess: uses a cylindrical board with quadrilateral cells. Armies consist of fairy pieces gryphon, dabbabah, pao, raja, etc. By Glenn E. Overby (2002).
- Tri-Chess: a three-player variant using an irregular hexagon board with triangular cells. Chancellors and cardinals replace queens. By George Dekle Sr. (1986).
The introduction of a third player drastically alters the style of play, even when standard pieces are used. Many chess openings are useless due to the extended board and third player. Each player must think twice as far ahead—anticipating the moves of both opponents, with the added complexity that the next player may move to attack either opponent.
If a player trades off pieces with a second player, the third player benefits. Hence, players will be more reluctant to make trades. Players often avoid such trades so as to carry out other strategies.
The introduction of the 'extra' move by the third player can introduce situations of deadlock, for example, if a white piece is undefended and simultaneously attacked by both black and red pieces. Black cannot take the white piece, since Red would then capture the black piece next turn. Thus the black and red pieces are both simultaneously attacking the white piece and defending it from attack by the other player. In similar situations, a piece can move quite safely to a square where it is attacked by both opponents, since neither opponent would take the piece and risk capture by the third player.
In games where the third player loses as well as the checkmated one, players must concentrate not only on their own attack and defense, but also on preventing the two opponents from checkmating one another. A player can take advantage of one opponent's position to checkmate the other, but must be careful that the third player does not checkmate first. White could checkmate Red, only to have his piece captured by a black piece, which checkmates Red. In this situation, White would lose since Black delivered the final checkmating move. This strategy also applies to games which give the checkmating player command of the checkmated opponent's pieces – a player who allows the second player to checkmate the third would surely go on to lose due to the increased power of his remaining opponent, now armed with the third player's pieces.
- Four-handed chess
- Game of the Three Friends
- Game of the Three Kingdoms—a three-player xiangqi variant using a hexagonal board with quadrilateral grids
- Sannin shogi—a three-player shogi variant using a hexagonal board with hexagonal cells
- Pritchard, D. B. (2007). "Games for three". In Beasley, John. The Classified Encyclopedia of Chess Variants. John Beasley. pp. 333–41. ISBN 978-0-9555168-0-1.
- Schmittberger, R. Wayne (1992), "Three-Player Games: The 'Petty Diplomacy' Problem", New Rules for Classic Games, John Wiley & Sons, Inc., pp. 44–5, ISBN 978-0471536215
- Trichess by Christophe Langronier
- Trio-Chess The Chess Variant Pages
- Three Player Chess by Hans Bodlaender, The Chess Variant Pages
- US3,652,091 Three-Player Chess board – Robert Zubrin
- Self's Three-Handed Chess The Chess Variant Pages
- Waidder's Three-Handed Chess The Chess Variant Pages
- Chess for three
- Megachess at BoardGameGeek
- Triple Chess The Chess Variant Pages
- Nikos Sidiropoulos and Rasmus Bro (2009). "In memory of Richard Harshman". Journal of Chemometrics 23: 315. doi:10.1002/cem.1247.
- ThreeWayChess.org including free downloadable rules
- 3 Man Chess: A Review by David Howe, The Chess Variant Pages
- 3 Man Chess in the Round official website