Editing Janus Chess

{{Short description|Chess variant played on a 10x8 board}}
{{Use mdy dates|date=September 2023}}
{{Use American English |date=September 2023}}
{{Chess diagram 8x10
| tright
| 
|rd|ad|nd|bd|kd|qd|bd|nd|ad|rd
|pd|pd|pd|pd|pd|pd|pd|pd|pd|pd
|  |  |  |  |  |  |  |  |  |  
|  |  |  |  |  |  |  |  |  |  
|  |  |  |  |  |  |  |  |  |  
|  |  |  |  |  |  |  |  |  |  
|pl|pl|pl|pl|pl|pl|pl|pl|pl|pl
|rl|al|nl|bl|kl|ql|bl|nl|al|rl
| '''Janus Chess''' initial position. The januses (knight+bishop compounds) start on the b- and i-files.
}}

'''Janus Chess''' is a [[chess variant]] invented in 1978 by Werner Schöndorf<ref name="CECV">{{cite book |last=Pritchard |first=D. B. |authorlink=David Pritchard (chess player) |editor-last=Beasley |editor-first=John |title=The Classified Encyclopedia of Chess Variants |publisher=John Beasley |year=2007 |contribution=Janus Chess |page=124 |isbn=978-0-9555168-0-1 }}</ref> from [[Friedrichsthal|Bildstock]], Germany. It is played on a 10×8 board and features a [[fairy chess piece]], the ''[[princess (chess)|janus]]'', with the combined moves of a [[bishop (chess)|bishop]] and a [[knight (chess)|knight]]. The janus piece is named after the Roman god [[Janus (mythology)|Janus]] because this god was usually depicted with two faces looking in opposite directions.

==Description==
The usual set of [[chess piece]]s is extended with two [[pawn (chess)|pawn]]s and two januses per player. Each janus is placed between a [[rook (chess)|rook]] and a knight. The relative position of the [[king (chess)|king]] and [[queen (chess)|queen]] is reversed compared to [[chess]]. After [[castling]], the king stands on either the b- or i-file and a rook stands on either the c- or h-file, depending on which side castling is done.

The janus is considered almost as powerful as a queen and is usually valued at about 8 points (based on [[Chess piece relative value|chess piece value]]s with pawns valued at 1). It is the only piece in the game that is able to [[checkmate]] the opponent's king without the assistance of any other piece, with the king in a corner and the janus two squares away on a diagonal, but this checkmate cannot be {{chessgloss|forced mate|forced}}. Due to the extra pieces, each player starts the game with considerably more "{{chessgloss|material}} power" compared to standard chess; however, the game has only a slightly higher material "power density",<ref>vickalan (Jan 22, 2017). "[https://www.chess.com/forum/view/chess960-chess-variants/comparison-of-material-power-in-variant-chess-games Comparison of Material Power in Variant-Chess Games]", ''Chess.com''.</ref> since there is more room for players to maneuver pieces because of the larger board (10×8 = 80 squares). Due to the different board and pieces, players are unable to use normal chess [[Chess opening|opening theory]], and chess [[Endgame tablebase|tablebases]] have limited value in the [[Chess endgame|endgame]].

Janus Chess has been popular in Europe<ref>[https://brainking.com/en/GameRules?tp=40 Game rules (Janus Chess)], ''BrainKing.com''.</ref> with regular tournaments drawing strong players.<ref name=CECV /> Several chess [[Grandmaster (chess)|grandmasters]] have played this game including [[Viktor Korchnoi]], [[Péter Lékó]] and [[Artur Yusupov (chess player)|Artur Yusupov]]. Korchnoi said: "I like playing Janus Chess because one can show more creativity than in normal chess."<ref name=CECV />

==See also==
[[Chess engine]]s that play Janus Chess:
* [[ChessV]]
* [[Fairy-Max]]

==References==
{{reflist}}

==External links==
* [http://www.chessvariants.org/large.dir/janus.html Janus Chess] by [[Hans L. Bodlaender]], ''[[The Chess Variant Pages]]''
* [http://www.janusschach.de/ Janusschach] Janus Chess {{in lang|de}}
* [http://www.brainking.com BrainKing.com] play Janus Chess over an Internet server.

{{Chess variants|state=collapsed}}

[[Category:Capablanca Chess variants]]
[[Category:Chess variants]]
[[Category:1978 in chess]]
[[Category:Board games introduced in 1978]]