Wednesday, October 05, 2016

Playing with Composition

In this post we will start from a nice miniature by our friend Nikos Pergialis and we will enhance it with more variations.
A miniature has up to 7 pieces.
Adding pieces to it, the problem will not be a miniature anymore, which was a limiting factor for old chap Nikos, but it will get more variations, which is my goal.


Problem-825
Nikos Pergialis (GRE)
8/8/8/rS6/3b4/1Q6/p1K5/k7
(3 + 4)
#2
Try : {1.Qb4? [2.Qe1# / Qxd4#], 1…Bb2 2.Qxb2#, 1…Bf2 / Be3 2.Qb2# / Qc3#, 1…Bc3 2.Qxc3#, 1…Rxb5!}

Key : 1.Sc3! [2.Qb2#],
1…Bxc3 2.Qxc3#,
1…Rb5 2.Qxa2#

The key is quasi-sacrificial. It closes one line allowing one mate, and also supports the wQ for the second mate. There are three mates in total.

The pieces are relocated two columns to the right.
A wRb6 was added, to keep bK from escaping to the second column.
A wBb1 was added, to allow promotion of bPc2 to knight, stoping the threat. A bRa1 was need to stop some duals from occuring. When bPc2 captures, the wQ mates from square d1.
A bPe4 can capture the wQ with check, but then a wSe5 mates.
The bQ can deter the threat, but then wRh7 mates. The presence of this rook offers a try, which allows us to see the Pseudo-Le Grand theme.

Problem-826
Emmanuel Manolas (GRE) (after Nikos Pergialis)
original
7q/7R/1Rr5/3SS1b1/4p3/3Q4/2p1K3/rBk5
(7 + 7)
#2
Tries : {1.Rxh8? [2.Rh1#], 1…Bd2 2.Qxd2#, 1…Be3 2.Qxe3#, 1…Bh4 2.Qd2# / Qe3#, 1…Rxb6 / Rf6 / Rh6 2.Qxc2#, 1…exd3+ 2.Sxd3#, 1…Bh6!},
{1.Qd4? [2.Qg1# / Qb2#], 1…cxb1=Q 2.Qd1#, 1…cxb1=R 2.Rxc6# / Qd1#, 1…Rxb6!}

Key : 1.Se3! [2.Qd2#],
1…Bxe3 2.Qxe3#,
1…Rxb6 / Rd6 2.Qxc2#,
1…Qd8 2.Rh1#,
1…cxb1=S 2.Qd1#,
1…exd3+ 2.Sxd3#

The problem works with similar mechanism, as the previous one, only it has now 14 pieces and there are six different mates. 

There is also the Theme Pseudo-Le Grand : "Two threats (A, B) in two phases, reappear crosswise as mates after different black responses (a, b) in these phases".
In the present problem the relevant moves are as follows
1.Rxh8? [2.Rh1# (A)] Bh4 (a) 2.Qd2# (B), 1…Bh6!
1.Se3! [2.Qd2# (B)] Qd8 (b) 2.Rh1# (A)

1 comment:

Ramesh Abhiraman said...

I enjoyed the post. Comins Mansfield Art of the Composition is one of my favorite books on the art of the chess problem