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Chameleon echo models in S# max. and R#
by Nils Adrian Bakke, FIDE-master in composition 1990

What are echo model mates and chameleon echo model mates? We find the answer by studying diagram 1. After the try 1. Qc4? (1. - h3!) Black may play 1. - Kxh1 answered by 2. Qf1+ Kh2 3. Bf4#. In the solution 1. Qf5!, 1. - Kxh1 is answered by 2. Qh3+ Kg1 3. Be3#. These two model mates are so-called echo model mates.*)


We continue our investigation: 1. Qc4? Kg1 2. Qxh4 Kf1 3. Qe1# and 1. Qf5! Kg1 2. Qh3 Kf2 3. Qg2#. These are chameleon echo model mates .



What is the difference, then? In echo model mates the black king occupies squares of the same color, while in chameleon echo model mates the black king changes from a dark to a light square (or vice versa!). In this example by Fossum we note that in the first chameleon model wQ occupies a dark square and bK a light one. In the second chameleon model this is switched: wQ mates on a light square the bK which now stands on a dark one.
In ordinary selfmate problems this is an everyday occurrence. The Czechs have investigated the possibilities here thoroughly. In selfmate maximummers and reflex-mates, however, this is virgin soil. Diagram 2 is a most acceptable showing. Probably this is the only ordinary selfmate maximummer with triple chameleon models.
Solutions to diagram 2 and the following diagrams are placed at the end of the article.


Diagram 1
André Fossum
14. All-round 1973/74
#2 C+ 11+7
Diagram 2
Nils Adrian Bakke
Norsk Sjakkblad 1999
Tilegnet Jiri Jelinek
S#3 Max. C+ 4+9

Diagram 3 and Diagram 4 are attempts to avoid (by-pass!) the difficulties by using several solutions. I wonder what the reader thinks of these two problems?

Diagram 3
Nils Adrian Bakke
The Problemist 1999
Tilegnet John Beasley
S#3 Max.
3 solutions
C+ 5+2

Diagram 4
Nils Adrian Bakke
Original
S#5 Max.
3 solutions
C+ 8+7

Then on to the reflex-mate problems. As early as 1975 I made Diagram 5, a reflex-mate miniature with chameleon echo. Unfortunately it had just two echo mates, but it was an easy task to remodel it, so it now shows three chameleon model mates.
Diagram 6 was a sensation when it was published in THE PROBLEMIST. The Russian composer, who is not quite unknown, managed to show three chameleon mates in a miniature. Note that wK, wRR, and bP all participate in the chameleon echo model mates.

Diagram 5
Nils Adrian Bakke
V. Feenschach 1975
Reflex-#2 C+ 4+3
Diagram 6
Viktor Chepizhny
The Problemist 1997
Reflex-#5 C+ 5+2

Diagram 7
Nils Adrian Bakke
Norsk Sjakkblad 1998
Reflex-#5 C+ 16+2

In Diagram 7 I had to employ two promoted wSS, but the position is legal! I wouldn't exactly claim that it was easy to compose this problem!

Solutions:
Diagram 1.
Try: 1 Qc4? Kxh1 2 Qf1+ Kh2 3 Bf4#.
1 - Kg1 2 Qxh4 Kf1 3 Qe1#, but 1 - h3!
Solution: 1 Qf5! Kxh1 2 Qh3+ Kg1 3 Be3#.
1 - Kg1 2 Qh3 Kf2 3 Qg2#;
1 - h3 2 Be3 Kxh1 3 Qxh3#.

Diagram 2.
1 Rf6! a5 2 Qe1 Qxe1 3 Kb5 Qb4#.
1 - b5 2 Qf1 Qxf1 3 Rcf2 Qc4#;
1 - e5 2 Qb2+ Qxb2 3 Kd5 Qd4#.



Diagram 3.
1 h6 Qa6 2 Kh5 Qf1 3 Qf5+ Qxf5#.
1 R4h3 Qa6 2 Kh4 Qf1 3 Qf4+ Qxf4#.
1 R1h2 Qa6 2 Qf3+ Qf6 3 Kh3 Qxf3#.



Diagram 4.
1 Rc3 Qb8 2 Rxe6+ Qd6 3 Kd1 dxc3 4 Rf6 Qxf6 5 Qc2 Qf1#.
1 Rd3 Qb8 2 Rxe6+ Qd6 3 Ke1 cxd3 4 Rg6 Qxg6 5 Qd2 Qg1#.
1 Re3 Qb8 2 Rxe6+ Qd6 3 Kf1 dxe3 4 Rh6 Qxh6 5 Qe2 Qh1#.



Diagram 5.
1 Ka5 tr 2 Ra4 Qb6#.
1 - Qxb4+ 2 Ka6 Qb6#;
1 - c6 2 Rc4 Qb5#;
1 - c5 2 Ka4 Qxb4#;
1 - Ka1 2 Rb5 Qa3#.



Diagram 6.
1 Kc3 bxa5 2 Rac2 a4 3 Kb2 a3+ 4 Kc1 a2 5 Rgd2 a1Q#.
1 - b5 2 Rad2 b4+ 3 Kc2 b3+ 4 Kd1 b2 5 Rge2 b1Q#;
1 - bxc5 2 Rae2 c4 3 Kd2 c3+ 4 Ke1 c2 5 Rgf2 c1Q#.



Diagram 7.
1 Se1 dxc5 2 b8R c4 3 Rb2 c3 4 Re2 c2 5 Sgf3 cxd1S#.
1 - d5 2 Rg4 d4 3 g3 d3 4 Kg2 d2 5 Sf2 dxe1S#;
1 - dxe5 2 Rg4 e4 3 Qb8! e3+ 4 Kg3 e2 5 Kh2 exf1S#.



*) The echo-diagrams are added by the web-master.