1.Kc7, 2.Kd6, 3.Kd5, 4.Ke4, 5.Kf3, 6.Kg3, 7.Nf3, 8.Rd5, 9.Nf5, 10.N5xd4, 11.Nb5, 12.Qc5, 13.g1=B, 14.Be3, 15.Bxd2, 16.Ba5, 17.d2, 18.d1=Q, 19.Qh1, 20.Qxh6, 21.Qh3, 22.Kh4!!
Half of those moves look utterly pointless, but the idea is now revealed: a position has been reached in which, had it been in a real game, White's previous move could only have been advancing the pawn from g2 to g4. Black may therefore capture en passant! So the solution continues 23.fxg3! 24.g2, 25.g1=B, 26.Bh2, 27.Bb8, 28.Bac7, 29.Kxg5, 30.Kf6, 31.Ke7, 32.Kd8, 33.Kc8, 34.Rd8, 35.Qd7, 36.Bb7+ when White mates with cxb7.
And why did Black wait until move 29 before playing Kg5? Because any earlier would have left White with no possible previous move. The game would be a draw by retro-stalemate.Reuse content