The Solution
Despite their length, serieshelpmates are usually quite easy to solve. The technique is the same
as for helpmates, first the mating position must be identified and then the method of reaching it
determined. Serieshelpmates lend themselves to unusual effects involving pawn promotion. This is
one example. Serieshelpmate in 30.
White will mate by Ne6 after Black's four pawns have promoted and occupied the squares c8, d7, e7
and e8. At present only one Black pawn can move, so the first four moves are easy.
1...b5
2...b4
3...b3
4...b2
Now Black faces the first promotion decision. After the pawn promotes, it will have to free
another pawn as it moves towards its final destination. The obvious pawn to take is the one on
f5, but should Black promote to a Bishop or a Queen? If Black takes a Queen, and then plays
...Qxf5, then he cannot move to c8 (as this would be check) and it is no good blocking d7,
because then Ne6 won't be mate. This suggests that a bishop is the correct choice.
5...b1B
6...Bxf5
The bishop should not move to d7, as this would prevent the final mate.
7...Bc8
8...f5
9...f4
10...f3
Now Black has to choose whether to promote on e1 or on f1. The answer comes from considering
which type of piece will capture White's pawn on d5 to release the d6-pawn. It cannot be a Bishop
or Queen, because this would give check, so it must be a Rook or a Knight. A Rook appears
possible, since afterwards it could move to e5 and e8, but this appears unlikely because after
...Rxd5 and ...Re5, there is no visible reason why Black should not play either ...d5 or ...Re8
next (the order of Black moves is always unique in a serieshelpmate). This suggests that a Knight
takes on d5, which is plausible because it could move to its final destination (e7) in only one
move.
11...f2
12...f1N
13...Ne3
14...Nxd5
15...Ne7
16...d5
17...d4
18...d3
Again, Black has a choice of promotion square, but now it is easier. By promoting to a Queen on
e1, Black can remove the pawns on h4 and h5 without loss of time, and then head for e8.
19...dxe2
20...e1Q
21...Qxh4
22...Qxh5
23...Qe8
Now the last pawn heads for the first rank.
24...h5
25...h4
26...h3
27...h2
28...h1R
29...Rd1
Finally... 30...Rd7
31 Ne6 mate.
The curious feature of this problem is that each of the four Black pawns had to promote to a
different piece.
Puzzle 0514
