Checkmate in six moves!

by Arne Kaehler
6/11/2020 – Stuart Rachels is not only a former chess prodigy and great writer, he also made some beautiful chess puzzles. We are happy to showcase four self-mate riddles which are worth looking at. They are creative in a way, that the white king has to be check-mated in as little moves as possible, on a certain square.

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Chess puzzles by Stuart Rachels

We recently had an interview with Rachels about his new book. He was kind enough to share some of his unique chess puzzles with us. They are construction tasks, and even if you aren't too big of a fan of such puzzles we highly recommend to look at them nonetheless. They are very creative!

Construct a chess game that ends in...


As you know you can move the pieces on each of the diagram boards and try to construct games that end in the way specified.

Construct a chess game that ends in...


In problem three the white king simply has to move to his queen's square and await a painful checkmate. In problem four, for a change, the black king will be checkmated in the corner. That he gets mated by the white king is indeed special.

Congratulations to any reader to find the solutions. These problems are very hard to solve!

Arne Kaehler, a creative thinker who is passionate about board games in general was born in Hamburg and learned how to play chess at a very young age. Through teaching chess to youth teams and creating chess content on YouTube, Arne was able to extend this passion onto others and has even made an online chess course for anyone who wants to learn how to play this game. Currently, Arne blogs for the English news page of ChessBase and focuses on creating promotional and entertaining articles.
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Fritzpa Fritzpa 6/30/2020 11:16
Many thanks for the symmetrical selfmate in 8 Zvi Mendlowitz

It took me a couple of hours this morning and I've posted the solution in the same LiChess study if people want to look.

Also finally got the second solution of 6...Rh3 mate with a redundant White move.

Cheers, Jon
Fritzpa Fritzpa 6/29/2020 11:39
At the end of the stream we were trying to solve 6...Rh3 mate with White having a redundant move. I've finally got one of these but apparently there is another with WK on another square. If you want to see mine then it's at:

(chapter 6)


Zvi Mendlowitz Zvi Mendlowitz 6/27/2020 01:02
Here is a problem you may enjoy.
Black imitates the moves of White, for example if White plays 1.b4 then Black plays 1...b5, if then White plays 2.Nh3 then Black plays 2...Nh6 etc. If this "mirroring" is not possible Black plays a random move. If Black must play according to the above rules, how can white selfmate in 8 moves?
mikalziane mikalziane 6/27/2020 10:40
Thanks for the nice stream Jon. Sorry I was not able to watch it live. It is quite interesting to see how a GM approaches these problems.
lnlver lnlver 6/26/2020 04:50
I have to congratulate everyone who solved #1. The solution's two themes intertwine to converge into a seemingly impossible result. If the solution were unique this would be a fantastic composition. For that reason, I like the problem 6) g x f8 N# more. I wonder how Sam Loyd would approach these constructions. Would he be dismissive or embrace them?
Fritzpa Fritzpa 6/25/2020 05:28
Hi again people,

I hope people enjoyed the stream and please do say here or email me at if you solve 6...Rh3 mate with a redundant White move - which is apparently possible with wK on two different squares. If anybody would like to download the stream as a .mp4 then it's at this address:


Frits Fritschy Frits Fritschy 6/25/2020 01:08
1 g3 h5 2 Bh3 g6 3 Kf1 d5 4 Kg2 Bf5 5 Kf3 Bh6 6 Bg2 Be4# is one possibility. Qg5 instead of Bh6 is also possible. Not suited for a problem, however, because there are just too many transpositions. Apart from that, the play is rather dull. A solution with e3 and K to d3 is even simpler.
Zvi Mendlowitz Zvi Mendlowitz 6/25/2020 07:26
Is there a game which ends in 6...Be4# with the white king NOT on b1?
Is there a game which ends in 6...Bxe4#?
Frits Fritschy Frits Fritschy 6/24/2020 09:33
Too bad I didn't get any sound. Probably my fault somehow. I hope solutions will also be here on the site.
Don't know whether the 'big hint' (#1) that Jon referred to was mine, I really thought it was only a mate in 7. Only later, checking my premises, I found that the one saying that black needs 3 moves to get his bishop to e4 was false. After that it was easy.
Fritzpa Fritzpa 6/24/2020 07:03
Just going live now at
Zvi Mendlowitz Zvi Mendlowitz 6/23/2020 05:17
@ GM Speelman:

Labelle has here some problems which are missing from the page you linked to:
VincentM VincentM 6/21/2020 05:28
@lnlver, yes for the diagonal, no and no for the rest ;-)
The key is to find the mininum number of BLACK moves to bring the bB to e4.
lnlver lnlver 6/21/2020 03:51
#1) I'm trying to figure out where the black bishop was before 6) ... Be4. It has to be on the a8-h1 diagonal. Which square is it and why is it on that particular square? Most likely candidates are c6, d5 and f3. That would probably make Black's d-pawn move d6. Is my thinking correct?
mikalziane mikalziane 6/20/2020 09:52
Thanks GM Jon Speelman for the link to François Labelle's page and looking forward to your stream.
brelenat brelenat 6/20/2020 01:31
I did'nt solve nr1 but , I created one:
9-Txa3++ Black King in h8. Not difficult...
mikalziane mikalziane 6/19/2020 02:22
It would be interesting to write a program to solve these puzzles using deduction rather than exploring variations. Pitrat did that long ago to play chess games but failed as brute force (alpha beta and heuristics) is so much more effective in chess in general.
mikalziane mikalziane 6/19/2020 02:14
The so called big hint for #1 is not necessarily one I think. I read it several times and it did not help me at all as long as I was stuck thinking how many moves such color must use to do this or that.
mikalziane mikalziane 6/19/2020 02:11
A very general hint so acceptable I think is that tempi can be exchanged between black and white so that when one think white has to do this maybe black can do it or help and vice versa. Also, more obviously, a single move may serve more than one purpose.
Fritzpa Fritzpa 6/19/2020 01:55
Hi again people,

I will do a stream on these on Wednesday June 24th starting at 1800 British time 1700 GMT at

Yes there is a big hint about #1 hidden in the comments which I should have picked up days before I finally solved it.

Incidentally #3 is cooked or rather there is a solution other than the other that Stuart Rachels intended.
I wrote to him about this (found the cook but not his solution) but didn't realise, as he pointed out to me, that as a result you can shorten the solution by half a move so that it becomes 8 Kxc1 mate with the black king on d8.

I'll look at all four of these and any other proof tasks such as the ones on Francois Labelle's page: next Wednesday.
Frits Fritschy Frits Fritschy 6/19/2020 10:29
Brelenat, what helped me: check whether all your premises are tenable.
VincentM VincentM 6/19/2020 10:24
I found the solution of #1 once I realized that the ideas/assumptions were corrects, but the realization (the moves)... not so much.
Don't know if we can post HINTS or not, so I won't for the moment...
brelenat brelenat 6/19/2020 06:20
Nr1, I give up. Waiting the solution...
VincentM VincentM 6/18/2020 11:43
I just put the board on before getting to bed for just one last try, and 1min later got it... Yeah ! ;-)
mikalziane mikalziane 6/18/2020 07:00
My reasoning was wrong and the solution is superb.
mikalziane mikalziane 6/18/2020 06:57
Finaly got #1 so I removed my possible spoiler as it is indeed a spoiler.
mikalziane mikalziane 6/18/2020 05:23
@vincentM your variation with the sub promotion is interesting but yes doomed as black only has 3 moves to help.
On the other hand capturing on c2 is fine as the king can take back in its way to b1.
mikalziane mikalziane 6/18/2020 05:15
@VincentM posts cannot be edited only removed so I could not fix my typo: take c2 OR d2 and take the knight.
mikalziane mikalziane 6/18/2020 05:13
Is there a tool to query about all possible games that abide some constraints ? Obviously that would be cheating to solve here puzzles but I wonder if such tool exists maybe even chessbase although it is more into querying played games than possible games.
VincentM VincentM 6/18/2020 05:06
If you solve the c2-d2 problem by capturing the pawns, you need 4 moves (e.g. c5, Qa5, Qxd2, Qxc2) and in the meantime the white pawns are in the way of the wK.
I tried:
1. d4 ç5
2. Kd2 çxd4
3. Nç3 dxc3+
4. Kç2 b6
5. Nd2 çxd2
6. Kb1 Bb7
7. Qe1 Be4++

I tried:
1. Na3 b5
2. c4 b4
3. Nc2 b3
4. d4 bxc2
5. Kd2 cxd1=N
6. Kc2 Bb7
7. Kb1 Be4#

It's not possible to block the d2 pawn (d3 has to be free), so d2 is either captured or pushed to d4. c2 square must be freed so pushing the pawn seems "logical" (capturing the pawn on c2 occupies the square so it costs two moves: the capture and the retreat. Capturing these pawns with black pawns costs too much time (at least 4 moves)...
It drives me crazy !
mikalziane mikalziane 6/18/2020 04:49
My reasoning does not lead to a solution so it is either wrong or based on wrong assumptions. Stuck.
mikalziane mikalziane 6/18/2020 04:46
Assuming b5 Bb7 Be4 is mandatory Black has 3 moves to take in d2 and c2 and the white knight. The only solution I see is b4xc3 then c3xd2 but then the white King is stuck and the white queen must go to as bad square instead of e1.
mikalziane mikalziane 6/18/2020 04:27
Assuming Black does not take on b1 or d1 he must take on d2 or c2 and take the white knight after it has moved or white does have time to move the knight out of way and solve his other issues.
mikalziane mikalziane 6/18/2020 04:11
Thank you VincentM. good point!
mikalziane mikalziane 6/18/2020 04:07
#1 white cannot afford 2 pawn moves or he does not have time to remove both the knight and the queen of the way of Be4 unless black takes on b1 or d1.
VincentM VincentM 6/18/2020 04:01
@mikalziane, Solution says Be4 not Bxe4, so it's not working (especially since problem #2 explicitly marks a capture: Bxg7)
mikalziane mikalziane 6/18/2020 03:17
2 knight moves that end on e4 allow black to win a tempo although white lose one. Could be used in some variations maybe.
mikalziane mikalziane 6/18/2020 02:05
About #1 one has to consider a bishop that would be promoted instead of the original Bc8. Promotion requires 5 moves so only h1 is possible. But then a pawn going to h1 hardly helps with all the issues to address so Bc8 goes to e4.
mikalziane mikalziane 6/18/2020 01:52
It would be interesting to see what reasonings can be made about those puzzles without of course too big spoilers. I have long been fascinated with the challenge to mix reasoning and computation in chess and other activities. Some conclusions have been made here already although some are tentative.

Obviously the white king needs 3 moves to reach b1 since castling quite out of the question. So there are only 3 other white moves. As already said the white rook a1 and bishop c1 as well as pawns a2 and b2 likely stay too even though this is not absolutely clear but it does not matter since one first looks for the simpler solutions. The c2 and d2 pawns must go or be taken as well as Nb1 and Qd1. Taking the Nb1 seems to fail as already explained so it must move once then be taken as two knight moves seems too expensive. Qb1 is hard to take so must move once (to e1 unless it is then taken). Unless the black Bc8 does all the job as in one close attempt that leaves a2 empty it seems that black have 3 forced moves b5 (or less likely b6) then Bb7 and Be4. It leaves them with 3 moves to help. I can’t believe I can’t find 3 white and 3 black moves which suggests my reasoning is wrong.
Is this correct and what other deductions can be made ?
mikalziane mikalziane 6/18/2020 12:43
Another close attempt that also only fails to 7. Qc2 is 1. c4 b5 2. Nc3 b4 3. Qa5 bxc3 4. Kd1 Bb7 5. Kc2 cd 6. Kb1 Be4+
Fritzpa Fritzpa 6/17/2020 03:16
Hi people,

Yes I think a stream would be fun

I guess we should wait a little so that people can have a good go. What about a week today Wednesday June 24th which is apparently a rest day in the Chessable Masters. I could do maybe an hour or so of them from 18-19 my time which is 17-18 GMT; 19-20 in Germany and the afternoon in different bits of the US. We could do these four and any others people bring. Have you seen the list by Francois Labelle at

the stream will be at