Defensive Resources

Problem number 30 in Anthology of Chess Combinations has elements of the first problem in the volume, a well-known mating pattern. The first problem is from Paulsen -- Morphy, 1857. In number 30, however, White has additional defensive resources. Determining the correct sequence of moves for defeating these defensive efforts requires deeper calculation.

Black to move

I quickly found the first few moves while drinking my morning coffee. Near the end, however, I faltered. I missed the key deflection that seals the deal.

It is an interesting quirk of the Anthology of Chess Combinations that White's best moves are given in the notes. The mainline leads to checkmate, but with different defensive moves, Black ends the combination with a decisive material advantage. The attacking theme is preserved, but players trying this problem against a computer must be prepared for a stubborn defensive effort that is not executed by the Chess Informant Solver's Kit, the software packaged with the CD version of the Anthology.