The winner will qualify for the GB team for the 2027 World Solving Championship, an event where they are often a medal contender The winner will qualify for the GB team for the 2027 World Solving Championship, an event where they are often a medal contender This week’s puzzle is a chance to enter an annual national competition in which Guardian readers traditionally perform well and in considerable numbers. White in the diagram, playing as usual up the board, is to play and checkmate in two