chess
Chess is a board game for two players, called White and Black, each controlling an army of chess pieces in their color, with the objective to checkmate the opponent's king. It is sometimes called international chess or Western chess to dist ...
-like abstract strategy board game using lasers that was formerly known as Deflexion. Players take turns moving Egyptian-themed pieces around the playing field, firing their low-powered
laser diode
The laser diode chip removed and placed on the eye of a needle for scale
A laser diode (LD, also injection laser diode or ILD, or diode laser) is a semiconductor device similar to a light-emitting diode in which a diode pumped directly with e ...
after each move. Most of the pieces are mirrored on one or more sides, allowing the players to alter the path of the laser through the playing field. When a piece is struck by a laser on a non-mirrored side, it is eliminated from the game.
Under its original name, the game was a Mensa Select Award winner. Its name was changed on September 15, 2006. The new game retains the same rules of gameplay, but has a different design, including a new color scheme and a new box design. Under the new name, the game was one of five finalists for the 2007 Toy of the Year award.
History
Professor Michael Larson and two students, Del Segura and Luke Hooper, designed the game as a class project at
Tulane University
Tulane University, officially the Tulane University of Louisiana, is a private research university in New Orleans, Louisiana. Founded as the Medical College of Louisiana in 1834 by seven young medical doctors, it turned into a comprehensive pu ...
. (Professor Larson is now at the
University of Colorado
The University of Colorado (CU) is a system of public universities in Colorado. It consists of four institutions: University of Colorado Boulder, University of Colorado Colorado Springs, University of Colorado Denver, and the University o ...
.) The game was introduced to the public in the spring of 2005, and was first brought to prominence at the New York Toy Fair of that year. The game was first shipped in October 2005. The first Deflexion World Championship was held December 10, 2005 under the dome at the
Massachusetts Institute of Technology
The Massachusetts Institute of Technology (MIT) is a Private university, private Land-grant university, land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern t ...
. Registration was free, and the participants competed for cash and other prizes. The winner was an MIT student.
Under the new name, ''Khet'', the first Regional Championship took place in April 2006 at the famous
Café du Monde
Café du Monde (French for "Café of the World" or "the People's Café") is a renowned open-air coffee shop located on Decatur Street in the French Quarter of New Orleans, Louisiana, United States. It is a New Orleans landmark and tourist ...
French Quarter
The French Quarter, also known as the , is the oldest neighborhood in the city of New Orleans. After New Orleans (french: La Nouvelle-Orléans) was founded in 1718 by Jean-Baptiste Le Moyne de Bienville, the city developed around the ("Old S ...
. Twenty-four participants competed for a number of prizes. As a special bonus, the
Eye of Horus
The Eye of Horus, ''wedjat'' eye or ''udjat'' eye is a concept and symbol in ancient Egyptian religion that represents well-being, healing, and protection. It derives from the mythical conflict between the god Horus with his rival Set, in ...
beam splitter
A beam splitter or ''beamsplitter'' is an optical device that splits a beam of light into a transmitted and a reflected beam. It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding wid ...
was unveiled at the very end, and used by each player in the championship game. Khet was also featured on a recent episode of the
HGTV
HGTV (an initialism for Home & Garden Television) is an American pay television channel owned by Warner Bros. Discovery. The network primarily broadcasts reality programming related to home improvement and real estate. As of February 2015, ...
show "I Want That: Tech Toys". Footage from the New Orleans tournament was included in the broadcast.
In 2017 a company called "Thinkfun" acquired the license for the now out of print Khet 2.0 and rebranded the game "Laser Chess". Now with a new, modernized scifi look, it brings the exact same rules and feel of Khet 2.0 back to the table.
Gameplay
Each player starts the game with 14 playing pieces (12 in Deflexion) on a 10x8 board, arranged in one of several predefined configurations, and a laser. The board has some squares (right file, left corners) that are restricted to pieces of one side or the other, preventing the creation of impenetrable fortress positions. In the original game, the lasers were built into the gameboard; in the "Khet 2.0" version, the lasers are instead built into two extra
Sphinx
A sphinx ( , grc, σφίγξ , Boeotian: , plural sphinxes or sphinges) is a mythical creature with the head of a human, the body of a lion, and the wings of a falcon.
In Greek tradition, the sphinx has the head of a woman, the haunches o ...
playing pieces, which can be rotated as a player's turn even though they cannot be moved from their starting positions. Scarab (formerly "Djed") and Pyramid pieces have mirrors (one on the Pyramid, and two on the Scarab) positioned such that when the laser beam strikes a reflective side, it reflects at a 90° angle. Players try to position pieces in a fashion that allows the laser beam to reflect into the opponent's Pharaoh, thus winning the game; however, they must also try to protect their own Pharaoh from being struck by the laser beam at the same time. On each turn, a player either moves a piece one square in any direction, or rotates a piece 90 degrees clockwise or counterclockwise. After moving, the player must fire their own laser, and any piece of either color hit on a non-reflecting side (with the exception of Anubis in Khet 2.0 being hit from the front) is removed from play.
The pieces in the game are:
;
Pharaoh
Pharaoh (, ; Egyptian: '' pr ꜥꜣ''; cop, , Pǝrro; Biblical Hebrew: ''Parʿō'') is the vernacular term often used by modern authors for the kings of ancient Egypt who ruled as monarchs from the First Dynasty (c. 3150 BC) until th ...
(1 of each color): The Pharaoh is the most important piece for each side. If hit with a laser, it is destroyed and its owner loses the game. Similar to a
king
King is the title given to a male monarch in a variety of contexts. The female equivalent is queen, which title is also given to the consort of a king.
*In the context of prehistory, antiquity and contemporary indigenous peoples, the ...
in chess, the Pharaoh pieces are comparatively weak, and so are often not moved unless under duress.
; Scarab/
Djed
The ''djed,'' also ''djt'' ( egy, ḏd 𓊽, Coptic ''jōt'' "pillar", anglicized /dʒɛd/) is one of the more ancient and commonly found symbols in ancient Egyptian religion. It is a pillar-like symbol in Egyptian hieroglyphs representing st ...
(2 of each color): Scarabs (formerly called Djeds) consist primarily of large, dual-sided mirrors. They reflect a laser coming in from any direction, and thus cannot be eliminated from the board. Also, unlike other pieces, Scarabs may move into an adjacent square even if it is already occupied, by switching places with the piece found there (whichever color it may be). Thus, they are the most powerful pieces on the board, but must be used with care, as a move that puts one side of the mirror in a favorable position may expose the player to attack using the opposite side of the same mirror.
;
Pyramid
A pyramid (from el, πυραμίς ') is a structure whose outer surfaces are triangular and converge to a single step at the top, making the shape roughly a pyramid in the geometric sense. The base of a pyramid can be trilateral, quadrila ...
(7 of each color): Pyramids have a single diagonal mirror, and form the primary mechanism for directing the path of the laser. They are vulnerable to a hit from two of the four sides, and must be defended lest the player lose their ability to build paths of any size.
;
Obelisk
An obelisk (; from grc, ὀβελίσκος ; diminutive of ''obelos'', " spit, nail, pointed pillar") is a tall, four-sided, narrow tapering monument which ends in a pyramid-like shape or pyramidion at the top. Originally constructed by An ...
(2 in Deflexion, 4 in Khet 1, not in Khet 2): Large pillars with no mirrored sides, these are vulnerable to attack from any direction, and therefore useful mostly as an emergency sacrifice to protect another piece (such as the Pharaoh). In Khet 1, each player starts the game with four obelisks each; a laser hit always removes an obelisk.
;
Anubis
Anubis (; grc, Ἄνουβις), also known as Inpu, Inpw, Jnpw, or Anpu in Ancient Egyptian () is the god of death, mummification, embalming, the afterlife, cemeteries, tombs, and the Underworld, in ancient Egyptian religion, usually depi ...
(2 in Khet 2 only): Anubis replaced Obelisks in Khet 2.0; they have the advantage that, despite still being unmirrored, they are not affected by a laser strike on the front; they must be hit on the sides or rear in order to be eliminated.
;
Sphinx
A sphinx ( , grc, σφίγξ , Boeotian: , plural sphinxes or sphinges) is a mythical creature with the head of a human, the body of a lion, and the wings of a falcon.
In Greek tradition, the sphinx has the head of a woman, the haunches o ...
(1 of each color): In Khet 2.0, the Sphinxes hold the lasers. They may not move (each player's is located at their closest right-hand corner) but may be rotated in place so as to fire down the rank instead of the file. A Sphinx is unaffected by laser fire, whether the opponent's or its own reflected back upon itself.
Three opening setups are most commonly used: Classic, which is the standard starting configuration, and is the best setup for one's first time playing; Imhotep, which is a variation on the Classic setup that introduces new defensive possibilities; and Dynasty, which has a fairly even mix of offense and defense, and moves quickly. However, any configuration agreed upon by both players can be used. In Deflexion, half the pieces were gold, and half were silver. When the company changed the name to ''Khet'', the gold pieces were changed to red. In Deflexion, gold always goes first, and in Khet, silver always goes first.
Most new Khet players allow their opponents to "control" the game, and focus on attack or defense depending on the actions of their opponent. However, more experienced players often concentrate on quickly building up a strong defense, and then relentlessly attacking their opponent's pieces, aiming ultimately to reach the Pharaoh. Some take this strategy even farther, and spend almost the entire game focusing on creating an impenetrable defense, simply waiting for their opponent to make a fatal mistake, or to leave themselves open to allow a quick strike at their Pharaoh. As in
chess
Chess is a board game for two players, called White and Black, each controlling an army of chess pieces in their color, with the objective to checkmate the opponent's king. It is sometimes called international chess or Western chess to dist ...
, three-fold repetition of the position is a draw. The average game lasts approximately 10 minutes, however a game between experienced players may take much longer.
Expansions
Two expansions have been released for the game. The Eye of Horus beam splitter expansion adds a new piece that is similar to a Djed, but which splits the beam. When a beam strikes the beam splitter, half bounces off at a right angle, as with the other mirrored pieces, while the other half continues on directly through the mirror, thus creating two beams out of one and adding a new strategic element to the game. Eye of Horus beam splitters are available in gold and silver, for those who own the old Deflexion game, and in red and silver, for those who own the newer Khet game. With the expansion pack, each player receives one beam splitter, which replaces one of their Djeds.
The most recent expansion, released on May 15, 2008, is called "Tower of Kadesh". It adds a 3D element into the game by adding a second level to the game board. The base of the tower has four mirrors that bring the laser up to the top of the tower. In addition to moving a piece horizontally or rotating it, players may move a piece vertically up to or down from the tower, or may move or rotate the tower itself.
In January 2011, a new edition of Khet called "Khet 2.0" was released. The gameplay is still the same, but the board and the pieces got a new modern look. The expansions released for Khet 1.0 are not compatible with Khet 2.0, however, "The Eye of Horus 2.0" was released in 2011. There are plans to release "Tower of Kadesh 2.0" as well.
Video game versions
A multi-player, cross platform iPhone and iPad app was developed for Khet 2.0 by
Schogini Systems
Schogini Systems Private Ltd. is an ISO 9001:2008 Certified Software company that creates gaming and educational applications for iOS(iPhone, iPad), Android (operating system), Android. They develop E-commerce and electronics products too. Thi ...
of India and Innovention Toys. The AI engine for the app was developed by
Don Dailey
Don Dailey (March 10, 1956 – November 22, 2013) was an American longtime researcher in computer chess and a game programmer. Along with collaborator Larry Kaufman, he was the author of the chess engine Komodo. Dailey started chess program ...
Steam
Steam is a substance containing water in the gas phase, and sometimes also an aerosol of liquid water droplets, or air. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporizat ...
Second Life
''Second Life'' is an online multimedia platform that allows people to create an avatar for themselves and then interact with other users and user created content within a multi player online virtual world. Developed and owned by the San Fra ...