29 November 2020

Endgame Study Database

Harold van der Heiden has released the sixth edition of his definitive Endgame Study Database. The first version was released in 1991 and contained 23,358 studies. Subsequent expanded editions were released in 2000, 2005, 2010, and 2015. Keeping with this schedule, he plans a seventh edition in 2025. The sixth contains 93,839 studies. Each edition adds to the size, while also correcting errors found in previous editions.

More information is available on his website.

When I initiated the purchase process this morning, he sent me a PayPal invoice. Shortly after I paid the invoice, I received an email with download instructions. I installed it in ChessBase.

Poking around among the pawn endings brought this position to my notice.

White to move

M. Zinar 2020

The solution runs 77 moves, but in fact everything is quite simple.

Perhaps after I have used this resource extensively, I can write a full review. For now, I can say that I've read about it for many years, and have been on the cusp of purchasing it more than once. This morning when I saw the new edition had been released, I acted within minutes. I'm happy that I did.

27 November 2020


Last Saturday was the second local online tournament for the 2020-2021 youth chess season. In "Lessons from a Youth Tournament", I presented an overview of the event and two instructive games. Today's article features some positions where the player on move had an opportunity for immediate checkmate and did not seize the opportunity. Such moments are too frequent in youth play, and can make it difficult to watch youth games.

I remember the first tournament for the player of the Black pieces in the first position. He was young and was winning game after game, including some nice wins against seasoned competitors. Where did he come from? Who is coaching him? He still shows that he can hold his own among all but the very best local players, and even they must bring their A game or suffer the consequences.

I was watching this game as it transpired. Black had an unstoppable checkmate that could be delayed and disrupted by a queen sacrifice, but could not be stopped. He played the first move while I was watching. I then waited for what seemed a long time for the final move and the end of the game. Checking the game times this morning, however, I discovered that this long wait was less than thirty seconds.

Black to move

He played 26...Qd5, threatening checkmate on g2. His opponent blocked the immediate mate with 27.f3. Black still had a mating attack, but it was more complicated. He missed it, too, and White's queenside pawns turned the material advantage back in favor of the first player who eventually won the game.

Our youngest player thoroughly dominated in round two, reaching this position.

Black to move

36...Qxe1+ is still a winning move, of course, but not the move that checkmates. Several moves later, Black suffered the fate of so many youth players who achieve overwhelming force against a weaker opponent: stalemate.

In the final round, the kindergartner once again had a good game with a forced checkmate in two. The first move in the sequence, 29.Nd6+ was played.

White to move

The game continued another eleven moves with White kicking the Black king around. After the game, we learned from a parent that Black offered a draw and White refused, but the game was drawn anyway. I had been watching the conclusion and thought I saw a repetition, which was communicated to the parent. Careful checking confirmed that a position had been reached for the third time with Black on the move each time when Black offered the draw. The game could have ended victoriously for White earlier.

Black won this next game in 63 moves via checkmate, but it is move 35 here.

Black to move

The oldest player missed a forced checkmate in two from this position, although she did win a few moves later. That game was featured in the post linked above.

White to move

In a battle between two second graders, the victorious player missed a quicker finish from this position.

White to move

Finally, Black found checkmate on the second move from this position, but it is available now.

Black to move

Having seen many similar examples of missed checkmates over twenty years of coaching youth players, I have developed a large number of resources for teaching checkmate patterns. Some fifteen years ago, I wrote a small booklet, "A Checklist of Checkmates", that I incorporate into my awards curriculum (see "Knight Award Problems"). Inquiries concerning this pamphlet can be submitted through the contact link on the right. My self-published Checkmate and Tactics (2019) contains a fair number of checkmate exercises and its "glossary" explains some of the most common patterns. Forcing Checkmate (2017) consists of a series of exercises that begin with fifty checkmates in one, then two, then contains a number of exercises where checkmate can be forced in longer sequences up to nine moves. It offers good practice for youth players.

Despite these available now, last weekend's tournament has motivated me to develop additional materials. Young players, in my opinion, should be regularly solving simple checkmate exercises on a regular basis. You cannot win the game if you cannot find checkmate.

23 November 2020

Lessons from a Youth Tournament

What can we learn from the play of a group of young players ranging in skill from beginners to seasoned tournament players? I think we can learn quite a bit.

After running the pairings and watching the games of twenty youth players from grades kindergarten through tenth grade, I have been going through their games carefully. There are examples of finding and executing tactical sequences to achieve a decisive advantage, or even a long-term initiative. But, there are also instances of giveaway chess, where a player seems unconcerned with vulnerability. Queens and lesser pieces are placed en prise, and sometimes left alone.

There are well-executed checkmates, and there are draws that followed from a young player missing a simple checkmate in one move. Two games featured three-fold repetition, but only one was claimed. Thirteen of the 49 games lasted 25 moves or less (miniatures), while seven games lasted fifty moves or more. Some of the miniatures revealed strong opening preparation.

King's pawn openings were most popular with the Italian Opening leading. Nearly one-third of the (15) games are classified C50 in the Encyclopedia of Chess Openings. Six games began with a move other than 1.e4. One player played 1.d4 three times, while another played 1.Nf3 twice. One game began 1.e3, and one wonders whether it was a mouse slip.

Black and White had an even score, each winning 23 games. Three games were drawn. Twenty participants played 49 games.

Illustrative Games

The first illustrative game pits the eventual tournament winner against one of the youngest players, a second grader.

A Boy (1157) -- A Girl (1634) [C50]
Turkey Trot (1), 21.11.2020

1.e4 e5 2.Bc4 Nf6 3.Nf3 Nc6 4.Nc3 Bc5

White to move

This position appeared in six games in the event.

5.0-0 0-0 6.d3 h6

Black, who is one of my students, understands how a pin of the knight can be a bother in such positions.

7.Bd2 d6 8.Qe2 Oblivious to the danger?

8.h3 prevents the pin

8...Bg4 9.Be3

Keeps the knight off d4

9...Bd4 10.Nb5 a6

White to move



11...exd4 12.Nxd4?? 

The game losing blunder. 12.Bd2 Ne5 and Black still has a clear advantage.

12...Bxe2 13.Nxe2-+ Qe7 14.Nf4 Qe5 15.Ne2 Ng4 16.Bd2


16...Qxh2# 0-1 

Another Italian Four Knights took a different course. When Black blundered, White seized the initiative, winning some material and bringing pressure against the king. It was enjoyable to watch this game as it progressed, trying to find for myself the surest finale.

Another Girl (1446) -- Another Boy (930) [C50]
Turkey Trot (3), 21.11.2020

1.e4 e5 2.Bc4 Bc5 3.d3 Nf6 4.Nf3 Nc6 5.0-0 d6 6.Nc3 Bg4 7.h3 Bd7 8.Be3 Bxe3 9.fxe3 Nh5??

White to move


10.Bxf7+ is even better 10...Kxf7 11.Nxe5+ Kg8 12.Nxd7 Qxd7 13.Qxh5+-


10...Nxe5 11.Qxh5 0-0±

11.Qxh5 g6 12.Bxf7+ Ke7

12...Kf8 13.Qh6+ Ke7 14.Qg5+ Kd6 15.Rf6+ as in the game.

13.Qg5+ Kd6 14.Rf6+ Be6

White to move


15.Rxe6+ is less strong, but is what I might have played. 15...Kc5 16.Rxe5+ Nxe5 17.Qxe5+ Kc6 (17...Kb6 18.Qb5#) 18.Bd5+ Kb6 (18...Kd7 19.Qe6#) 19.Na4+ Ka5 20.Bc6+ Qd5 21.Qxd5+ Ka6 22.Bxb7#

15...h6 16.Qxg6

I wanted her to find 16.Bc8+ Kc5 17.b4+ Kxb4 18.Rxc6!! bxc6 (18...Qxg5 19.Rb1+ Ka5 20.Rb5#) 19.Qxe5 Ka3 (19...Qxc8 20.a3#) 20.Rb1 Qd5 21.Qxd5 cxd5 (21...Rb8 22.Qa5#) 22.Rb3#


White to move


Again, I was looking for17.Bc8+! Kc5 18.d4+ exd4 19.Na4+ (19.exd4+ Qxd4+) 19...Kb5 20.Bxb7; 17.Bc4+ Kc5 (17...Kd7 18.Qf5+ Ke8 19.Rf8+ Rxf8 20.Qg6+ Rf7 21.Qxf7#) 18.Na4#

17...exd4 18.exd4 Nxc2

White to move


My persistent idea is clearly better here: 19.Bc8+ Qxf6 20.Qxf6#

19...Kd7 20.Qf5+ Ke8 21.Re6+

21.Rf8+ Rxf8 22.Qg6+ Rf7 23.Qxf7#

21...Kd7 22.Re5+ Kd6 23.Qe6# 1-0

There are other lessons possible from many of the other 47 games. Perhaps I will write more another day.

12 November 2020

Checkmating Patterns

I recently added to my bookshelf A Modern Guide to Checkmating Patterns (2020) by Vladimir Barsky. This book extends the work of two older books that are scarce and therefore expensive: Victor Henkin, 1000 Checkmate Combinations (2011), and Mikhail Tal and Victor Khenkin, Tal's Winning Chess Combinations (1979). The latter two books were published in Russian sometime before the English editions came out. I have a hunch it was a single book with two English editions. Tal's introduction "Don't Re-invent the Wheel" in the 1979 text appears as "Don't Reinvent the Bicycle" in the 2011 version with some differences. 

I have a hardback copy of Tal's Winning Combinations that I bought in the past decade, but passed up a chance to buy the Batsford edition, 1000 Checkmate Combinations. My recollection of when and where I looked at it does not correspond to the publishing date because I think it was a few years before 2011. I failed to comprehend then the significance of my opportunity. There is a Kindle version of the Batsford edition. The diagrams are a bit pixilated, but clear enough on my iPad.

All of these books arrange checkmate patterns according to which pieces effect the execution of the enemy king. Barsky credits Viktor Khenkin, The Last Check with the "methodology" (7). A Modern Guide to Checkmating Patterns is wholly new. Barsky assembles illustrative positions and exercises exclusively from the twenty-first century. This one caught my eye this morning in the opening chapter.

White to move

The position arose in Lenderman,A. -- Gareyev,T., Mesa 2010. Lenderman played 30.Rd6 and Black resigned. The rook's interferes with the defensive contact between Black's queen and rook, threatening Qxb8#.  White's queen is safe from capture because of Black's weak back rank. Any move of Black's rook dooms the knight. Barsky gives 30...Rc8 31.Ra6 Nc4 32.Qxc4 Rxc4 33.Ra8+ with mate to follow (12-13).

A few years ago, when I was reading Tal's Winning Chess Combinations, I was struck by the quality of the examples. Barsky's examples also seem rich with possibilities. The book serves not only to teach elementary patterns, but also to stimulate the imagination.

Khenkin's original approach to discerning and organizing checkmate patterns is worthy of attention. It varies slightly in the three books that I have before me. Listing the table of contents of each of the three will serve to highlight the continuities while also marking slight differences in the approach.

Tal's Winning Chess Combinations Contents:

1. The Rook
2. The Bishop
3. The Knight
4. The Queen
5. The Pawn
6. Two Rooks
7. Queen and Bishop
8. Queen and Knight
9. Rook and Bishop
10. Rook and Knight
11. Two Bishops
12. Two Knights
13. Bishop and Knight
14. Three Pieces

1000 Checkmate Combinations Contents

1. The Rook
2. The Bishop
3. The Queen
4. The Knight
5. The Pawn
6. Two Rooks
7. Rook and Bishop
8. Rook and Knight
9. Two Bishops
10. Two Knights
11. Bishop and Knight
12. Queen and Bishop
13. Queen and Knight
14. Three Pieces

The first two books offer the same chapters, but the sequence differs. The content is similar, but the Batsford edition contains more exercises. In the new book by Barsky, the number of chapters is reduced by combining pawns and the three chapters featuring minor pieces into a single chapter.

A Modern Guide to Checkmating Patterns Contents

1. The Rook
2. The Queen
3. The Minor Pieces and Pawns
4. Two Rooks
5. Rook and Bishop
6. Rook and Knight
7. Queen and Bishop
8. Queen and Knight
9. Queen and Rook
10. Three Pieces

10 November 2020

Informant 145

Chess Informant 145 is now installed in ChessBase. If only I can find the time to pursue my chess study. Exercises open in solving mode.