A Kriegspiel Endgame

Abstract

Kriegspiel is one of the most interesting variants of chess: each player tries to mate his opponent, using ordinary chessmen and following the ordinary rules, but neither player knows where the other player’s pieces are. Instead, both players have a concealed board on which they can keep track of their own position and guess at the locations of the opponent’s pieces. There is also a third participant in the game, namely the kriegspiel referee; he has a third set of chessmen, with which he keeps the actual position. When it is White’s move, White suggests a possible move to the referee. If it is legal in the actual game position, it becomes White’s official move; otherwise White must try additional moves until one is legal. Then it is Black’s turn, and the game continues in this fashion. Any legal move that places the opposing king in check is announced to both players. There are other rules (which do not concern us) that involve captures and pawn moves; further details can be found in [1].