|Problem 822: Francesco Simoni - Helpmate|
(17.04.2017) Happy to publish this complex helpmate from the Italian master! It is another ideal example of the 'Organised disharmony' popularised by Zivko.
822. Francesco Simoni (Italy)
H#2 3 Sol. (6+14)
1.Bxc3 Rxg4 (Sxg4?) 2.Bf6 Re4#
1.Rd6 Sxg4 (Rxg4?) 2.Rf6 Sf2#
1.g5 h5 (Rxg4? Sxg4?) 2.Rf6 Bxg4#
Tries fail for want of tempo W1.
1.Bxc3 ~? 2.Bf6 Bxg41.Rd6 ~? 2.Rf6 Bxg4
Three solutions with the common strategy of selfblocks in the same square by different pieces. In the solutions 1.Bxc3 and 1.Rd6, if white had a tempo move, it could mate with 2...Bxg4, but white doesn't have such a move, so it forms a battery in W1, with reciprocal dual avoidance for the indirect white pin due to B1. It follows a battery mate with Switchback.
In the third solution, instead, the pawn move 1.g5 prevents the previous strategy, but the selfblock in g5 allows 2...h5 to guard g6, so the mate Bxg4 is now possible. (Author)
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