White to play and mate in two moves. (White moves, Black moves, White then checkmates.) There is only one move White can make which will allow certain checkmate of Black in its next move, so the puzzle is finding that first move. That first move can involve any legal move, including checking the Black King or taking a Black piece. When White’s first move, (the “Key”), is discovered, White in its next move can checkmate Black in 4 ways, depending on where Black moves.
Composed by Mark Avery
The solution is below.
Think you have it? Do you think the first move involves . . .
the bishop moving to b2? Then, when the Black king takes the knight, White’s queen moves to b4? But it’s not checkmate, because Black’s knight can block the check.
the rook moving along the (a) line? No. Taking Black’s knight? No. Black’s king takes the pawn on d6.
The queen moving along the b line? No.
The king moving? No.
A pawn moving? No.
The solution: The Key is moving the knight on g8 to f6.
If Black’s king moves to d4, White’s bishop moves to b2. Checkmate.
If Black’s king takes the knight on f6, White’s queen moves to h8. Checkmate. (The bishop can’t mate because Black’s pawn can block the check.)
If Black’s king takes the knight on f4, White’s pawn jumps to d4 revealing the bishop. Checkmate.
If Black’s king takes White’s pawn, White promotes the pawn on c7 to a knight, revealing the queen. Checkmate.
More chess problems:
1. The Straitjacket. Medium
2. The Samurai. Medium.
3. The Dog’s Collar. Medium.
5. The Harridan. Difficult.
6. Fiddler’s Elbow. Difficult.
7. Laurel & Hardy. Two puzzles with a surprise. ‘Laurel’ is easy; ‘Hardy’ is difficult.
(Try also the blog, ‘If God played chess’ and answer the questions posed.)