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A problem where some preliminary decoying of the black force is necessary before the mainplan can be executed.
The solution will appear here on Thursday 28th July.
If White tries an immediate 1.Sxh7, threatening 2.Qg5+ Kxh7 3.Qg7, Black has an adequate defence in 1...Be3, after which 2.Sf8, threatening 3.Qg6 is met by 2...Be8. White could decoy the bishop to f4 by means of 1.Rc7 (threat 2.Rxh7 mate) Bxc7 2.Sxh7 Bf4, but after 3.Sf8 Be8 still defends successfully. White must also decoy this bishop by 1.Rc2 (threat 2.Rh2 mate) Be2 2.Rc7 Bxc7 and now the mainplan works. 3.Sxh7 Bf4 4.Sf8 Bh5 5.Qxf4. This type of strategy, where a piece can successfully defend against a threat by moving on to a line, but is decoyed so that it defends on a different square on the same line, where it creates an exploitable weakness, is known as a Roman decoy.
Peter Niehoff: The black bishop on b6 is steered to c7 so that the white queen can capture him on f4 (capture Roman) . But first the black bishop on b5 must go to h5 (block Roman)!
Dafydd Johnston: The manoeuvre of the rook followed by the knight switchback, and the unexpected mating position, make for difficult but very rewarding solving.
The solution to this problem will be posted here on Thursday 28th July, which is a day earlier than normal. After that, the next weekly
problem will not be posted until at least Tuesday 9th August.
Any comments or questions on this problem should be addressed to
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