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The Chess Variant Pages

This page is written by the game's inventor, John Smith.

Conditional Quantum Chess

The title of this game refers to quantum uncertainty. In this game, like in quantum mechanics, the inner workings of things are unknown, or even absolutely ambiguous. In the game's case, it is which move is the real move. It is conditional for one because it describes how players can choose their real move based on their opponent's, and also because the name "Quantum Chess " is already taken.


Same as FIDE Chess, but you'll need an extra for every piece type.


Same as FIDE Chess.


Same as FIDE Chess, except:

Whenever you move, you may move to two locations, whether it be with one piece or two pieces. After your opponent's move, however, you reveal which was the real move, or, rather, your final move, as your choice may have been dependent on your opponent's response. There is also no check or checkmate. You lose if your King is captured. You are allowed to capture your own pieces if you could also capture your opponent's pieces. There is no distinction in notation with capturing from non-capturing moves. I recommend to play with Kings that can only use discrete moves. Otherwise they may be hard to mate.

Example opening (diagrams in links due to bandwidth):

1a. e4 ; Nf3
1a... d5 ; Nc6
1b. e4
1b... Nc6
2a. Nc3 ; Nf3
2a... d5 ; e5
2b. Nf3
2b... e5

This 'user submitted' page is a collaboration between the posting user and the Chess Variant Pages. Registered contributors to the Chess Variant Pages have the ability to post their own works, subject to review and editing by the Chess Variant Pages Editorial Staff.

By John Smith.
Web page created: 2008-11-23. Web page last updated: 2009-12-20