(2) Undoubling Lever

White to move.

1.Kc3

1...Kf7 2.Kd4

2...Bb7 3.e4 Ke7

[ 3...dxe4 4.Bxe4 Ke7 5.Ke3 Kd7 6.Kf4 Ke8 7.Kg5 Kf7 8.Kh6 Ba8 9.b5 axb5 10.Bg6+ Ke7 11.a6 Kd8 12.Kg7 Kd7 13.Kf6 Kd8 14.Bf7 Kc7 15.Kxe6 Kc8 16.Ke7 Kc7 17.Kf8 Kd7 18.e6+ Kd8 19.e7+ Kd7 20.e8Q+ ]

4.Be2 Kf7 5.exd5 White undoubles his e4 and e5 pawns with a Undoubling Pawn Lever

5...exd5 6.Bg4 Ke8 7.Ke3 Kd8 8.Kf4 d4 9.Ke4 d3 10.Kxd3 Ba8 11.Ke4 Ke7 12.Kf5 Kf7 13.Ke4 Ke7 14.Bc8 Kd8 15.Bxa6 Ke7 16.Kf5

Taking the opposition, and preparing to advance the pawn

Kd8 17.Kf6 Ke8 18.e6 Kd8 19.Kf7 Kc7 20.e7 Kb8 21.e8Q+ Kc7 22.Qc8#

1-0