Pastimes: Chess

You are White and it's your move. A win looks unlikely - even if you capture all the black pawns, your bishop is on the wrong colour to promote the h-pawn - unless White's king can prevent Black's from reaching h8 to stop the pawn.

The immediate problem is what to do about the a-pawn. After the obvious 1.Bb1, Black plays 1...Kf6. Now 2.h7 Kg7 3.Kxe6 would lose to 3...c4 followed by c3 and c2. One of the black pawns will get through.

Instead, White can try 2.Ke8 when Black may force a draw with 2...a2 3.Bxa2 Kg6, or play for a win with 2...e5 3.Kf8 a2 4.Bxa2 Kg6. White may draw after 5.Bd5 Kxh6 6.Ke7, but it needs delicate calculation.

That line suggests the germ of an idea. Suppose, after 3...a2, White played 4.h7. Then 4...a1(Q) would lose to 5.h8(Q)+. Sadly Black plays 4...axb1(Q) instead when White is struggling, but it shows that something other than 1.Bb1 is possible. Let's try 1.Bishop somewhere between c2 and f5, Kf6 (1...a2 loses to 2.h7) 2.Ke8 a2. Now it seems a very long shot, but what about 3.Kf8 a1(Q) 4.h7 with the threat of h8(Q) mate? Obvious nonsense! Black can play either 4...Qa8+ or 4...Qh1. Unless there's a white bishop on e4. And that's it! White wins with 1.Be4!! Kf6 2.Ke8! a2 3.Kf8 a1(Q) 4.h7 either mating or winning the queen with h8(Q)+ next move.