the player does not see what is in front of their pawns, but knows if the position is occupied or not; pawn promotions remain unknown for the opponent. Before November 5, 2021 when a pawn could be taken en passant, the pawn was not visible, but the en passant square was lit up. Variations Generally, because basic Dark chess rules are universal with respect to its "parent" classical variant, any 2-player chess variant may be played "in dark". SchemingMind provides some of the variations. Dark chess (checkmate) – standard rules of check apply (a player is notified when its king is in check, and the king cannot move into check). The goal in this variation is the same as in standard chess — to checkmate the king. Dark chess (check) – a player is notified when the king is in check, but the king can remain in check after a move. The goal in this variation is the same as in standard dark chess – to capture the king. Dark crazyhouse – combination of crazyhouse and dark chess. Dark suicide – combination of suicide and dark chess. Sun Tzu chess – combination of Double Fischer Random Chess (like Chess960, but with different positions for White and Black), crazyhouse and dark chess. Pieces can be dropped onto any possible square on the board (like crazyhouse). This chess variant was invented in 2005 by John Kipling Lewis. Lao Tzu chess – like Sun Tzu, but pieces can only be dropped on seen squares. Also invented in 2005 by John Kipling Lewis. Dark Omega chess – combination of Omega Chess and dark chess. Dark Seirawan chess – combination of Seirawan chess and dark chess. Gameplay Dark chess has a strong strategic flavor. Planning and strategy, as well as some psychological reasoning, are very important; tactics and move searching are not as important as in standard chess. In this variant, a king should be carefully protected from very dangerous checks by invisible pieces; castling is essential, as the pawns and rook protect the king from invisible pieces. For a queen the most dangerous pieces are knights, which can attack it without becoming visible. See also Fog of war List of chess variants References External links Dark Chess Strategy guide Darkness chess by Jens Bæk Nielsen Dark chess by Tall Troll Games Chess variants 1989 in chess Board games introduced in 1989