Mate Or No Mate?

Submitted by eugen on Sun, 07/28/2024 - 10:28
PUBLICATION NOTE:
This article was published originally on The Chess Improver blog on 2016-09-27
I have reposted it here for reference.

"This is the end, beautiful friend
This is the end, my only friend, the end
Of our elaborate plans, the end
Of everything that stands, the end
No safety or surprise, the end ..."
The End, The Doors

This is such a deep and inspirational song! Have you tried to listen to it with your eyes closed and no other distractions around? I suggest you do it at least once. It will be an experience like no other!...

In chess the most exciting end is checkmate. You want to reach it on the winning side and avoid it on the losing side. I grew up learning the importance of knowing when to resign and from this point of view there was an unwritten rule of resigning when all hope was lost; as a result being checkmated was the ultimate humiliation reserved for patzers. In this new Millenium a lot of students are taught to play all the way to checkmate even in intercontinental play; not sure what is your opinion on it and I will stick with what I know. My students will mostly resign way before checkmate if needed!

Solving problems outside the box is a very popular concept and in chess it takes breathtaking forms. Over the years I collected such materials from the internet and I used them with extreme success at the club. Students are always thrilled of the challenge and engage fully. I guess they are more excited only when allowed to play bughouse which goes down the same alley. Here is one such doozy for you: white moves and DOES NOT checkmate in 1:
[Event "Puzzle #02"][Date "2016.09.19"][Result "1-0"][SetUp "1"][FEN "B5KR/1r5B/6R1/2b1p1p1/2P1k1P1/1p2P2p/1P2P2P/3N1N2 w - - 0 1"]
Common, give it a try before scrolling down! Do you feel special for tricking "the end" for one more move?...

I gave the above puzzle and a few similar ones to a couple of promising students as the admission test for this year at the club. They missed passing it at the end of June and I wanted to give them something appropriate instead of the same test they already did. Their reaction was typical: it started with "Are you kidding us? We will have the answer as soon as it is written down", to "What do you mean? We can figure out a few ways to solve it" and ended with a desperate cry "It is impossible!". Funny though neither gave up on it and continued to look at the board stubbornly, looking for the solution. One of them found a solution I had to argue with:
"White offers a draw!"
Now that is as outside the box as it can get, right? We had a good laught about it and it is the reason for writing this piece.

The other student took the engineering approach: started to eliminate the pieces and moves not helping:
1. Pawns were eliminated first
2. Knights followed: either Knight's move would checkmate
3. Rh8 was trapped
5. Kg8 was a non factor
6. The remaining pieces to look at were Ba8, Bh7 and Rg6. Did you notice the Bishops are on the same colour? You must be a good player.
Now by process of elimination Ba8 has only one move 1.Bxb7# we do not need and Bh7 cannot move, but he can deliver a nasty check when Rg6 moves. This finally brings us to Rg6 and we either see it or start trying all moves along the 6th rank:
a) 1.Rh6# as Rb7 is pinned
b) Immediately after this we see Rf6#, Re6#, Rd6#, Rb6# and Ra6# are similar with "a"
Now you got it for sure, the only move unpinning Rb7. Congratulations!
[Event "Puzzle #02"][Date "2016.09.19"][Result "1-0"][SetUp "1"][FEN "B5KR/1r5B/6R1/2b1p1p1/2P1k1P1/1p2P2p/1P2P2P/3N1N2 w - - 0 1"] 1.Rc6!! Rxh7