Invented in Jens Baek Nielsen and Torben Osted in 1989.
Implemented
by Andreas Kaufmann
(January 2003).
The rules as in standard chess, except that you don't see all enemy
pieces. You see
only positions attacked by your pieces, or positions where your pawns can go
to. The capture en-passant is not allowed. The promoted pieces are always
visible. You are not told if your king is in check. If you don't move it out of
check or put him into check yourself, the opponent can capture him and win the
game.
To play
black, select the second variant: “Dark Chess (Play for Black)” and then switch
sides. In the provided endgame variants, dark pieces are located initially on
the same positions as yours.
For after
game replay, press 'Switch Piece Set' button. All pieces in alternative piece
set are intentionally visible to let you see what happened in the reality.
There are 7
variants in zrf file: