## Thursday, May 29, 2008

### Helpmates (2)

We have said that the helpmates are heterodox problems, having different goal than the orthodox problems, that is in helpmates black plays first and helps white to give checkmate. Now we will see helpmate twins, helpmate duplex, and series helpmates.

Helpmate twin problems

Besides the multiple solutions, another way to give variety to the play of a helpmate is the construction of twin problems.
Thus, from one diagram more problems appear with small differences, such as the relocation of one piece, the addition or the removal of a piece, the turning of the chessboard to another direction, or some other differentiation.
there are twins in all types of problems, but they are more common in helpmates.

 (Problem 97) Henry Forsberg, ”Revista Romana de Şah”, 1935 (a) diagram : Helpmate in 2 (b) replacement of the Queen Qa6 with Rook Ra6, (-bQa6 +bRa6) (c) or with Bishop Ba6, (-bQa6 +bBa6) (d) or with Knight Sa6, (-bQa6) +bSa6) (e) or with black Pawn a6, (-bQa6 +bPa6) h#2 (3+2) [8/8/q7/8/1R4K1/k2S4/8/8]

The problem-97 is a helpmate two-mover, by Henry Forsberg, which was awarded First Prize in the Memorial Tourney for composer W. Pauly, the results of which were published in the magazine "Revista Romana de Şah" in 1935. The twins in this problem are created by replacement of the black Queen with various pieces. The solutions of the five problems are :

(a) With black Qa6 : Key: 1.Qf6! Sc5 2.Qb2 Ra4#

(b) With black Ra6 : Key: 1.Rb6! Rb1 2.Rb3 Ra1#

(c) With black Ba6 : Key: 1.Bc4! Se1 2.Ba2 Sc2#

(d) With black Sa6 : Key: 1.Sc5! Sc1 2.Sa4 Rb3#

(e) With black Pa6 : Key: 1.a5! Rb3+ 2.Ka4 Sc5#

Helpmate Duplex

Another method to take two problems from one position diagram is the Duplex problem.

 Duplex is a helpmate with two goals : in the one black plays and helps white to give checkmate, in the other white plays and helps black to checkmate.

(Duplex problems can also be composed for other types of problems, but in great majority they are helpmates).

 (Problem 98) Milan Vukcevich, First place, "Bucuresti vs Beograd" composition match, 1960 Helpmate in 2, Duplex h#2 duplex (3+3) [4K2s/3P1P2/4k3/3p4/8/8/8/8]

The problem-98, by the Yugoslavian composer Milan Vukcevich, was awarded first place in the Match "Bucharest vs Belgrade" in 1960. The solutions are :

Black plays first : Key: 1.Sg6! f8=Q 2.Se5 d8=S#.

White plays first : Key: 1.f8=R! Sf7 2.d8=B Sd6#.

These two solutions are closely related, with two pieces from white pawn promotions to cover the flights of the black King in the one solution, and two pieces from white pawn promotions to block the flights of the white King in the other solution.
Since the problem achieves the four promotions, is an Allumwandlung.

Series helpmate

 A helpmate is of type series, when the black plays without response from the white a series of moves, and then white with one move checkmates. Black King may not be exposed in danger, also black may not give check to the white King, except at the last move.

 (Problem 99) T. R. Dawson, ”Fairy Chess Review”, 1947 Series helpmate in 17 ser-h#17 (2+2) [8/8/8/S7/8/8/5p2/k1K5]

The problem-99 is a series-helpmate more-mover in 17 moves (short notation : ser-h17#), composed by Thomas Rayner Dawson, which was published in "Fairy Chess Review" in 1947.
An effective way for someone to solve series-helpmate more-movers like this is to try to imagine a position, where black can be checkmated, and to try "to bring" this position.
Here, where only a Knight exists, the only way for black to be checkmated is to be their king in the corner a1 and another black piece in a2, thus a mate with Sb3 is possible. The white King is in c1, so the black piece can not be a Knight because it would give check from a2. The mate is given from square b3, so the black piece in a2 can not be a Bishop or a Queen, because it would capture Sb3. So the promotion will give a Rook.
The need not to expose white King to check means that there is only one way to solve the problem, with the black King going to the middle of the chessboard and returning.
The solution is :

Key: 1.Ka2!
2.Ka3 3.Kb4 4.Kc3 5.Kd3 6.Ke2 7.Ke1 8.f1=R 9.Rf2 10.Ke2
11.Kd3 12.Kc3 13.Kb4 14.Ka3 15.Ka2 16 Ka1 17 Ra2 Sb3#
(or in short notation
1.Ka2-a3-b4-c3-d3-e2-e1 8.f1=R 9.Rf2 10.Ke2-d3-c3-b4-a3-a2-a1 17.Ra2 Sb3#)

Other types of helpmates

The helpmates, just as the other types of problems, can be composed with Fairy pieces or with rules of the Fairy chess, such as Circe chess, Grid chess, or Patrol chess.
Every variety can be combined with another, so there is a vast field for application of various ideas.

(This post in Greek language).