Solution to Endgame Study #5

Here is the solution/analysis for this week’s endgame study #5.

Composition by Paul Keres, Magyar Sakkvilág, 1936.
White to Play

1.Nc2+! Ka2

    [ 1…Bxc2 2.Qb8

        A) 2…b2+ 3.Kxc2 b1Q+ ( 3…h3 4.Qa8# ; 3…Ka2 4.Qa8# ) 4.Qxb1# ;

        B) 2…Bd3 3.Qa8+ Ba6 4.Qxa6# ;

        C) 2…Ka2 3.Qa7# ;

        D) 2…Bb1 3.Qxb3 Ba2 ( 3…c2 4.Qb2# ) 4.Qxc3# ]

    [ 1…bxc2 2.Qb8 Ka2 3.Qb4 Ka1 ( 3…Bd3 4.Qa4# ) 4.Qa3# ]

2.Nb4+! Ka1

    [ 2…Ka3 3.Nd3 Bxd3 4.Qd6+ Ka4 ( 4…Ka2 5.Qd5 Bb5 6.Qa8+ Ba4 7.Qxa4# ) 5.Qxd3

        A) 5…c2 6.Qc4+ Ka3 ( 6…Ka5 7.Qxb3 and White will gobble up the remaining pawns. ) 7.Qb5 b2+ 8.Kxc2 ;

        B) 5…Kb4 6.Qd4+ Ka3 7.Qxc3 Ka4 8.Qc5 h3 ( 8…b2+ 9.Kxb2 h3 10.Kc3 h2 11.Qb4# ) 9.Kb2 h2 10.Kc3 h1Q 11.Qb4# ;

        C) 5…h3 6.Qc4+

            C1) 6…Ka3 7.Qb5 b2+ 8.Kc2 h2 ( 8…b1Q+ 9.Kxb1 h2 10.Kc2 h1Q 11.Qb3# ) 9.Qb3# ;

            C2) 6…Ka5 7.Qxc3+ Ka4 8.Qxh3 ;

        D) 5…b2+ 6.Kc2 Ka3 ( 6…Kb4 7.Qxc3+ Kb5 8.Kxb2 h3 9.Qxh3 ) 7.Qxc3+ Ka4 ( 7…Ka2 8.Qxb2# ) 8.Qxb2 ]

3.Qa2+ bxa2 4.Nc6 h3

    [ 4…Bc2 5.Kxc2 h3 6.Nd4 h2 7.Nb3# ]

5.Nd4 h2

    [ 5…Bg8 6.Nc2# ]

6.Nb3#