Home of the Meson Chess Problem Database and the BDS Ladder

Chess Problem 2000h2f101

Jörg Kuhlmann & BDS

Phénix, 2000



1.Qa4! (2.Qd7 Qd6#)

1...Qa3 2.Qf4 Qh3#
1...Qf6 2.Qb5 Qh6#
1...Qb4 2.Qa3 Qb2#

In the diagram position, the white rook doesn’t check the black king, as, if it were to capture on f1, it would not be on a square adjacent to an occupied square. After the key, Black isn’t obligated to mate by ...Qe2, because that would be an illegal move – putting a piece next to the black king would mean that it would be in check from the white rook.

The threat is to occupy a square next to d6 so that Black can move there and mate because the mating piece would be immune from capture, not being next to anything else after such a capture. All three legal moves by the black queen defeat the threat. After 1...Qa3 White has to be careful to choose an arrival square for his only mobile piece that doesn’t disturb the potential mate on h3. A similar situation occurs after 1...Qf6, while after 1...Qb4 the white queen leads the black queen to a mating square, in much the same way as in the threat.

Composed in Cologne (Köln), where Jörg Kuhlmann has his home.

Developed and maintained by Brian Stephenson.
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