WINTON
BRITISH CHESS SOLVING CHAMPIONSHIP

John Rice

Mate in 2

1.Qa6!    (zz)

1 ...Qxd4+ 2. Ne5#
1 ...Qxc4 2. Rd3#, Rdd2# or Rd1#
1 ...Qxb3 2. Rd3#
1 ...Qxc2 2. Rd2#
1 ...Qb2 2. Nxb2#
1 ...Qa1 2. Nb2#
1 ...Qd3 2. Rxd3#
1 ...Qe3 2. Ncxe3#
1 ...Qd2 2. Rdxd2# or Nxd2#
1 ...Qe1 2. Nd2#
1 ...Rc8+ 2. Qxc8#
1 ...Rb7 or Ra7 2. Qc6#
1 ...Rc6 2. Qxc6#
1 ...Nb8 or Nf8 or Nf6 or Ne5 2. Qb6#
1 ...Nb6 2. Qxb6#
1 ...e6 or e5 2. Qd6#
1 ...bxc4 2. Qa5#

Unlike last year's problem this year white's key move has no direct threat, but Black was in zugzwang. Black has 22 legal moves, and all of them allow a white mate with 12 different white mating moves (not differentiating for captures)!

Many incorrect solutions duplicated the same ideas, with the majority being [illegal] moves by the rook on d4 which is pinned in the starting position. A breakdown of the incorrect solutions, and their frequencies are presented below: