# Question
Title: Why are USCF quick ratings lower than USCF regular ratings?
I noticed that my USCF quick rating is lower than my USCF regular rating. At first I thought maybe it was because I was relatively weaker at faster time controls, but it seemed like the difference was too large to be just that. This got me to looking at the ratings of everyone in my section (It was the open section, there was another section of sub-1200 and unrated) of my most recent dual-rated tournament. On average, the pre-event quick ratings of the 50-ish players in this tournament were 170 points below their regular ratings (and that even includes one player who never played quick before and was therefore given a provisional quick rating equal to his regular rating.)

It occurred to me that maybe I'm just in an area with local weirdness in the ratings, but that doesn't seem to be the case. Wesley So has the highest regular rating in the nation, but his quick rating is 166 points lower than his regular. The 100th best regular rating is 2474, but the 100th best quick rating is 2263, which is 211 points lower.

Although I know the player pools of the two rating systems are not identical, it would seem that the pools have significant overlap - all are USCF members who play in tournaments. Initial quick ratings are literally based on the regular rating, if the player was already regular-rated. And both rating systems appear to use the same algorithm to calculate ratings.

But despite that, quick ratings are significantly lower, apparently by nearly a full class. Why are they so much lower, given the same algorithm and many of the same players? And, assuming it's desirable that the ratings be similar, what could be done to correct this situation?

# Answer
This may be partially due to ratings floors.

When a player hits his rating floor, his rating cannot go lower if he loses, but his opponent's rating can still go higher. This adds ratings points into the system.

There is an absolute rating floor of 100 which nobody can go below. (For every event you play in and quarter-point you win over the board, this is raised by 1, to a maximum of 150.) Rating floors exist at every 100 points from 1200 to 2100, and these can be achieved by getting a rating at least 200 points above the floor. There's a rating floor at 2200 which can be earned by getting the Original Life Master title. And finally, if a player earns $4000 or more in an under-2000 section, their rating floor is set high enough so they become ineligible to win the prize again.

Regular and quick ratings both have ratings floors, but they are independent from each other. Most events with very large prizes are probably not quick-rated. And I don't think the Original Life Master title can be earned with a quick rating. This probably means that fewer people are at a floor with their quick rating, and that if they are, the floor is lower than it might otherwise be.

To add rating points to the system, it is insufficient for a player to simply be at the floor - he must actually play games. I would hypothesize that more regular-rated games are played than quick-rated games, especially at the 1200+ level where floors come into play. I would also hypothesize that older players are more likely to be at a floor (because they won a large prize sometime on their life, because they once managed to raise their rating beyond its ordinary level, or because their skills are not what they once were) and that older players in particular play more regular games than quick games.

And if younger people play relatively more quick games, that may be another reason why quick ratings are lower. Younger players are more likely to start with a very low rating but be rapidly improving. When a player's ability improves, his rating lags behind, and his opponents will tend to lose rating points. This tends to have a deflationary effect on ratings.
> 7 votes

# Answer
They are not really lower. That depends on the person.

Most lower rated players train the wrong way to be able to play speedier chess well, or at least better than very slow chess games.

GMs can play speed chess quite well and most would not have a lower speed rating than for slow OTB games.

Exacerbating the problem is digital clocks with all their weird add ons delays and similar gimmicks that drastically change the effect of playing faster on different people and their ratings.

OTOH I know a mere NM whose published speed rating is higher than his OTB. So again, it depends a lot more on the person than the ratings.

Also Exacerbating is the lumping of widely different speeds and related ability into one very wide category for the ratings.

With more rating categories the ability vs speed would be better shown although for most players there will be a maximum where they are as good as they can be so slowing down the time control would not raise their ratings more.
> 2 votes

# Answer
The reason is very simple: **There are more players playing regular than quick time control.**

What the rating algorithm says is that, **within a player pool**, the relative rating difference between two players should measure the relative strength between them. **The weakest player in each pool always has a rating of 100 and every other player's rating represents their strength relative to the weakest player** (assuming an ideal world where every player plays a lot). A rating in one player pool is incomparable to the rating in another player pool.

If we assume that each player pool has the same player strength distribution (e.g., a normal distribution), it follows that a player with the same percentile in both player pools gets an overall higher rating in the larger pool. Why? Because **the larger the pool is, the more likely that the weakest player in the pool is weaker**.

Your argument that regular and rapid pool have significant overlap don't matter. What matters is that they ultimate are very different in size. See the old stats: 65455 regular players vs 37162 quick players.

If you want to know whether you are stronger in regular or rapid, you can look up your percentiles in these two pools and compare them.

---

**Update**: To clarify one point: The difference between a player's quick rating and regular rating does not reflect a player's difference in the strength of the two groups of time controls, even though the two ratings are calculated under the same algorithm. This is because each player's rating are always calculated based on the player's strength in that group of time control relative to those of other players in that pool. The algorithm never calibrates the ratings between the two groups of time control.

If this seems hard to understand, try to replace the digits in a quick rating with alphabets (0 -- A, 1 -- B, 2 -- C, etc. e.g., rating 1230 becomes BCDA). Now you run the algorithms to compute a player's regular and quick ratings, you'll see that digits never encounters alphabets. Intuitively, a digital rating isn't comparable to an alphabetical rating. The algorithm never sets a bridge that calibrates the ratings in two different pools.
> 2 votes

# Answer
While floors contribute to it, the biggest reason for the difference is the fact that strong players are less likely to play quick rated tournaments as they improve. So their quick rating doesn't increase as fast as their regular. Here's an example scenario:

Tournament 1: Dual Rated. Regular Rating = 1000, Quick Rating = 998
Tournament 2: Regular rated only (longer time control). Regular rating: 1000 =\> 1100.
Tournament 3: Regular rated only (longer time control). Regular rating: 1100 =\> 1175.

So at the end of the day, your regular rating is 1175 but your quick remained at 998 . Then when you DO play a dual tournament again, you're quick rating is underrated and brings everyone else down. There are some crazy examples, of GMs like Awonder Liang with only 2100 quick ratings or so.

What USCF should do is automatically boost everyone's quick ratings to minimum 100 points lower than regular, if they want quick ratings to be accurate at all.
> 1 votes

---
Tags: rating, uscf
---


# Question
Title: How should I configure Stockfish if I want it to play as a 2800 ELO player without the UCI_LimitStrength value?
Stockfish has so many parameters that I'm not sure which one I should change so that it has a strength equivalent to that of a human who has 2800 ELO, well that's one of my wishes, the other is to be able to play against Stockfish at its maximum potential (3600 ELO), it is clear that I will lose but I don't care, I just want to play, the specifications of my PC are as follows:

-4GB RAM

-CPU 4Cores/4Threads

-Only HDD

I have been testing with the Skill Level parameter however I am not sure if that is enough as I am not a very strong player to know if Stockfish is playing better than a GM.

# Answer
> 3 votes
So couple of issues off the cuff;

Do you have a particular version in mind?

Chess engines don't exactly have "ELOs". Chess engines are about calculation speed, calculation depth. They guestimate (at best) to determine a theoretical strength then measure against other engines.

Stockfish 9 with 4 Cores is ~ 3200 "ELO" Stockfish 12 similar rig I would argue is around that 3400-3600 "ELO" Mark.

The Reality; Playing solely against engines, at the highest level is ill advised for any development and engines are best used for position analysis (if that).

# Answer
> 1 votes
You can change the depth of the Engine, 10 depth is around 2400 ELO, and depth 18 is 3200 ELO. The highest depth 99 is around 4050 ELO(approx. 4023 ELO)

---
Tags: engines, stockfish
---


# Question
Title: When can you tell which pieces are 'White' from a position where the pieces are colored red and green and you know whose move it is?
Suppose you come across a chessboard where the pieces are colored red and green and there are no labels on the squares. You don't know which move number it is.

What are the positions where, by only knowing whose move it is, you can determine which of the red or green pieces are the 'White' pieces?

# Answer
There are many positions where if you know whose move it is, you can determine who is Black and who is White for parity reasons, e.g. :

```
[FEN "nrb1kb1N/1ppppppr/p6p/8/nN6/P6P/1PPPPPP1/1RBK1B1R w - - 0 1"]

```

In this position, White has played an odd number of moves:

* two moves with pawns
* odd number of moves with the knights (because they both stand on dark squares)
* even number of moves with the Rh1
* odd number of moves with the Rb1
* odd number of moves with the Kd1
* No move with the other pieces, including the Qd1 that was taken on place by a black knight.

Meanwhile, Black has played an odd number of moves:

* two moves with pawns
* odd number of moves with the knights (because they both stand on light squares)
* odd number of moves with the Rh7
* odd number of moves with the Rb8
* even number of moves with the Ke8
* No move with the other pieces, including the Qd8 that was taken on place by a black knight.

We can deduce that both sides have played the same number of moves, and thus it's White to play.

Conversely, if you meet this position with red and green pieces and you know which side is on move, you can deduce that this side is White.

Alter the position with Pa7 -\> Pa8, and the conclusions are reversed : the side on move will be Black.

This will work for any legal position where no unit but queens has been captured, and all the pawns stand on their second rank, but the rook-pawns that may be on their second or third ranks.
> 8 votes

# Answer
For White, the king starts to the right of the queen; for Black, it's the opposite. Hence, if for only one side, the king, queen, bishops and b- up to g-pawn are still on their original square, you don't even need to know whose move it is to know who's White and who's Black.

```
[FEN "1nbqkb2/1pppppp1/8/8/8/8/1PPPPPP1/1NBQKB2 w - - 0 1"]

```

(the knights are there because some piece must have made the last move).

In some cases, like the diagram below, those pawns could actually be on the seventh row; if there are sufficient pieces from the other color, retrograde analysis can prove the position is not possible.

```
[FEN "2bqkb2/1pppppp1/8/8/8/8/8/4K3 w - - 0 1"]

```

I have a hard time thinking of a position where you can tell who's White and who's Black, *unless* you know who is to move. I suspect it might not be possible at all.
> 7 votes

# Answer
In the initial position, with red and green pieces, if you are told it's red turn then red must be white.

From the initial position, you can only reach the initial position by playing an even number of moves, thus both side must have played the same number of moves and thus it is white's turn.
> 3 votes

# Answer
Probably openings, checks and stalemate situations. Openings because you can for the first moves count who is to play, checks because it is always the turn of the player in check and stalemates because it is the move of the player that can make a move otherwise it already was a draw
> 1 votes

---
Tags: retrograde-analysis
---


# Question
Title: Why is the Budapest Defense considered not fully sound or even dubious? What theoretical difficulties arise for Black?
```
[fen ""]
1. d4 Nf6 2. c4 e5 3. dxe5 Ng4 4. Bf4 (4. Nf3 Bc5 5. e3) (4. e4 Nxe5 5. f4) (4. e3 Nxe5 5. Nh3)

```

White can choose from multiple setups, most common are 4. Bf4, 4. Nf3, 4. e4 or even 4. e3 with the deep idea of Nh3-f4-d5. Database results favor White heavily. Then again, legends with the caliber of Gelfand or Kramnik go down against it.

From what I gathered, people claim that Black has long-term strategical deficiencies, in many variations White can obtain the bishop pair and the positions are just "good for White". But what exactly are the problems Black faces when playing the Budapest?

---

EDIT: I have found an interesting line in the Adler-Maroczy Variation (4. Nf3), where I think Black does not have enough compensation. Surprisingly, it is not analysed in any Budapest book I own and played extremely rarely, even though this is the move White wants to play according to most analysis (why is it not checked then???) and it is almost entirely forced.

```
[fen ""]
1. d4 Nf6 2. c4 e5 3. dxe5 Ng4 4. Nf3 Bc5 5. e3 Nc6 6. Nc3 O-O (6...Ngxe5? 7. Nxe5 Nxe5 8. f4! Ng6 9. Bd3 {is regarded as very good for White and is warned against in almost all Budapest analysis}) 7. Bd3! (7. Be2 Ngxe5 {is normal and Black is fine}) Ngxe5 (7...Re8 8. Qc2 {Black has to somehow block the attack on h7, either by ...g6 or ...h6, both disabling the vital Black plan of Re8-e6-h6 with a kingside attack. White has ideas of returning the pawn on his terms with e6} (8. Bc2 {White achieves a good placement for his bishop without problems})) 8. Bxh7 Kxh7 9. Nxe5 Nxe5 10. Qh5+ Kg8 11. Qxe5 b6 {Black is a pawn down, in return has the bishop pair, but will probably have to forfeit it soon, as ...Bb7 will be blocked by Nd5. White can castle both sides after Bd2}

```

# Answer
It's definiely not a "bad" option for Black. It can be played at high levels and still get decent results. However, it's not considered a "great" line for many reasons:

* As you said, White has multiple set-ups to choose from most of them leaving them with a slight advantage.
* The "surprise factor" that may give Black with an edge against an unprepared opponent doesn't exist (at least not so early in the opening) at the highest levels.
* White only enters the Budapest if he wants. If he's worried that his opponent may go for it, he can just play 2.Nf3, most likely transposing later on to his favourite opening.

Database statistics should always be taken with a grain of salt, since there could be multiple factors biasing it (a particular player that uses it very often, or an opening being "the favourite" of weak players, or maybe an opening that is used as a surprise weapon against strong opposition). However I think the factors above prevent the Budapest from being a practical choice to build your repertoire around (specially reason #3: you'll still need something against 2.Nf3, say the King's Indian. You'll be able to use that against 2.c4 too, so you may just as well forget about the Budapest and focus on the King's Indian)
> 4 votes

# Answer
The Budapest Gambit is playable, even at top levels. That's different than, say, the King's Gambit which is legitimately dubious for strong players.

However, black has basically two choices:

(1) Don't recapture the pawn, but have insufficient compensation.

(2) Recapture the pawn, but wind up in a very slightly more difficult -- though technical equal -- position. Example:

```
[FEN ""]
1. d4 Nf6 2. c4 e5 3. dxe5 Ng4 4. Nf3 Nc6 5. Bf4 Bb4+ 6. Nbd2 Qe7 7. e3 Ngxe5

```

Black's pawns are still on the seventh rank, its minor pieces are vulnerable to attack, and its opponent controls the direction of the game. White is practically an extra move or two ahead, though analysis is essentially even.

---

The Budapest is most playable by:

* non-masters - opponent doesn't know the theory, easy to make early mistakes
* engines - can handle the technically equal middle game in the face of all of White's options

Masters are in an odd middle ground between those two, where you usually don't see the Budapest Gambit.
> 0 votes

---
Tags: opening, analysis, theory, 1.d4
---


# Question
Title: Has checkmate ever been achieved by castling kingside in a high-level game?
Has checkmate ever been achieved by castling kingside in a high-level game?

I asked an AI large language model, but it listed games which certainly didn't achieve checkmate with castling kingside. I also tried searching the web but didn't come across any.

# Answer
> 8 votes
According to that CQL query :

```
cql(input Megabase2023.pgn)

mate
move previous from [Kk] o-o

```

There are twelve games where the castling king side delivered a checkmate, 4 of which played by 1600+ players

---

```
[Title "Wiedermann, Daniel (2048) v. Wagner, Leopold Franziskus (2168) - Blitz Playchess.com (2020)"]
[FEN ""]

1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 Bxc3+ 5.bxc3 O-O 6.e4 d5
7.cxd5 exd5 8.e5 Nfd7 9.f4 c5 10.Nf3 Nc6 11.Bd3 c4 12.Bxh7+ Kxh7 13.Ng5+ Kg6
14.f5+ Kxf5 15.Qh5 Nf6 16.O-O#

```

```
[TITLE "Kreyssig, Bruno (1828) v. Heilmann, Karl Ludwig (1665) - Forchheim 12th 2013"]
[FEN ""]

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be3 Bg7
7.Be2 O-O 8.f4 Nc6 9.Nb3 Be6 10.g4 Na5 11.g5 Ne8 12.h4 Bc4 13.h5 Bxe2 14.Qxe2
Qc7 15.Nd5 Qd8 16.hxg6 hxg6 17.Qh2 f6 18.f5 fxg5 19.Qh7+ Kf7 20.fxg6+ Ke6 21.
Qh3+ Ke5 22.Bd4+ Kxe4 23.Nc3+ Kf4 24.O-O#

```

---

```
[TITLE "Moreno, Jose Enrique (1622) v. Pereira, Gerardo (1400) - Montevideo Duchamp Cup 1st 2017"]
[FEN ""]

1.e4 Nc6 2.d4 d5 3.e5 e6 4.Nf3 Be7 5.c4 b6 6.Nc3 Ba6 7.
cxd5 Bxf1 8.dxc6 Ba6 9.a3 h6 10.Be3 f6 11.b4 fxe5 12.Nxe5 Bf6 13.Qh5+ Ke7 14.
Ng6+ Kd6 15.b5 Qe8 16.Bf4+ e5 17.dxe5+ Kc5 18.Be3+ Kc4 19.Qe2+ Kxc3 20.Rc1+ Kb3
21.Qc4+ Kxa3 22.Rc3+ Kb2 23.Qb3+ Ka1 24.O-O#

```

---

```
[Title "Naqopia, Giorgi (1680) v. Nurijanyan, Alex (1610) - Poti op 14th 2019"]
[FEN ""]

1.e4 c5 2.b4 cxb4 3.a3 d5 4.exd5 Qxd5 5.Bb2 Nf6 6.axb4 Bg4 7.Ne2 Nc6 8.Nbc3 Qd7 9.h3 Bh5 10.Qb1 e5 11.b5 Nb4 12.Ba3 a5 13.bxa6 Rxa6
14.Ng3 Rb6 15.Bxb4 Bxb4 16.Ra8+ Ke7 17.Rxh8 Bxc3 18.Nf5+ Qxf5 19.Qxb6 Qe4+ 20.
Qe3 Qb4 21.f3 Nd5 22.Qg5+ f6 23.Qxg7+ Ke6 24.Qg8+ Kf5 25.Bd3+ Kf4 26.g3+ Kxf3
27.O-O#

```

---
Tags: history, checkmate, castling, famous-games, master-games
---


# Question
Title: Has checkmate ever been achieved by castling queenside in a high-level game?
*This is to complement the kingside variant of that question*

Has checkmate ever been achieved by a castling queen side in a high-level game?

# Answer
> 9 votes
According to that CQL query :

```
cql(input Megabase2023.pgn)

mate
move previous from [Kk] o-o-o

```

---

15 games had queen side castle deliver checkmate, including 5 by 2000+ players

---

```
[Title "Vlassov, Nikolai (2466) v. Wirig, Anthony (2422) - EU-ch Internet qual (2003, blitz) - Playchess.com"]
[FEN ""]

1.e4 c6 2.d4 d5 3.e5 Bf5 4.Nc3 Qb6 5.Nf3 e6 6.Bd3 Bxd3 7.
Qxd3 Qa6 8.Qxa6 Nxa6 9.a3 c5 10.Be3 h6 11.Nb5 Kd7 12.dxc5 Nxc5 13.b4 a6 14.Nc3
Ne4 15.Nxe4 dxe4 16.Nd2 a5 17.Nc4 Kc6 18.Nxa5+ Kd5 19.Bf4 g5 20.O-O-O#

```

---

```
[Title "Heimisson, Hilmir Freyr (2394) v. Fossan, Andreas (2025) - Nordic-ch U20 (2019)"]
[FEN ""]

1.e4 c6 2.Nc3 d5 3.Qf3 d4 4.Bc4 e6 5.Nce2 Ne7 6.Qg3 a5 7.
a3 b5 8.Ba2 Bb7 9.d3 Ng6 10.h4 Bd6 11.f4 Rg8 12.Nf3 Na6 13.h5 Ne7 14.Nexd4 Nc7
15.Be3 c5 16.Ne2 Nc6 17.Qf2 Na6 18.h6 Qc7 19.e5 Be7 20.Nc3 Qb6 21.f5 exf5 22.
Bxf7+ Kxf7 23.Ng5+ Bxg5 24.Qxf5+ Bf6 25.exf6 gxf6 26.Qxh7+ Ke6 27.Nd5 Kxd5 28.
Qf7+ Ke5 29.Rh5+ Rg5 30.Bf4+ Kxf4 31.Qxf6+ Kg3 32.Rh3+ Kxg2 33.Qf3+ Kg1 34.
O-O-O#

```

---

```
[Title "Garcia, Alvaro (2231) v. Gonzalez Parejo, Ramon Junior (2067) - COL-ch sf Medellin (2019)"]
[FEN ""]

1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nge2 c5 6.d5 O-O 7.
Ng3 Bg4 8.f3 Bd7 9.h4 Na6 10.h5 Nc7 11.Bf4 a6 12.Qd2 b5 13.Bh6 bxc4 14.Bxg7
Kxg7 15.hxg6 fxg6 16.Qh6+ Kg8 17.Bxc4 Nb5 18.e5 dxe5 19.Nge4 Rf7 20.Nxf6+ exf6
21.d6 Nxd6 22.Qxh7+ Kf8 23.Qh8+ Ke7 24.Nd5+ Ke6 25.Nf4+ Kf5 26.g4+ Kxf4 27.Qh2+
Ke3 28.Qd2+ Kxf3 29.Rh3+ Kxg4 30.Qg2+ Kf4 31.Rf3+ Ke4 32.Qe2+ Kd4 33.O-O-O#

```

---

```
[Title "Van Riemsdijk, Dirk Dagobert (2137) v. Queiroz, Stella Becker - Santos Paulista-ch (2011)"]
[FEN ""]

1.e4 c6 2.Nc3 d5 3.Qf3 d4 4.Bc4 dxc3 5.Qxf7+ Kd7 6.dxc3
b5 7.Bf4 bxc4 8.O-O-O#

```

---

```
[Title "Kablar, Dorian (1538) v. Hilby, Craig (2420) - Kasparov CF University Cup (Lichessm rapid, 2022)"]
[FEN ""]

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Nc3 Nf6 5.d3 d6 6.Bg5 h6 7.
Bh4 a6 8.O-O g5 9.Bg3 Na5 10.Bb3 Nxb3 11.axb3 h5 12.h3 h4 13.Bh2 g4 14.hxg4
Bxg4 15.Qd2 h3 16.Bg3 Nh5 17.Kh2 hxg2 18.Kxg2 Bh3+ 19.Kxh3 Nf4+ 20.Kg4 Qd7+ 21.
Kg5 Nh3+ 22.Kf6 Qe6+ 23.Kg7 Qg6+ 24.Kxh8 O-O-O#

```

---
Tags: history, checkmate, castling, famous-games, master-games
---


title: Can chess bots adapt to changes?

text:
# Question
Title: Can chess bots adapt to changes?
If there's a chess bot and I changed how the bishop moves so it can move through pieces can it beat me without the need to change the code?

# Answer
> 1 votes
No, at least if you're intending to use the rule change in your advantage. For instance, you could threat the enemy queen with pawns between them and there's no way for the computer to be aware of the danger, who will just let you take their queen for free. Think for instance 1.d4 d5 2.Bg5 and how is the computer supposed to know that it must move the queen away?

There are also situations where the computer would have to stop playing. After 1.e4 e5 2.Bb5 the computer will suggest an illegal move, as it doesn't know that ...Ke7 is the only legal move.

Since it's not aware of the rule change, it will also never use the rule tweak in its advatnage, so any reasonably skilled chess player would win the game easily.

# Answer
> 0 votes
There are engines that can play chess variants when told the rules in some chess variant description language. I think Fairy-Stockfish is the most widely used one. The github page for it claims that master-level strength can commonly be achieved just by giving it the rules of a user-defined chess variant, without adjusting it in any way. It claims that superhuman strength is usually possible when a fully trained NNUE network is used for evaluation. A training data generator is also available on github.

Disclaimer: I haven't used these tools myself, but I find these claims plausible. Fairy-Stockfish is used e.g. on lichess to provide computer opponents for various chess variants, and these computer opponents are known to be very strong, but I think these use NNUE networks to obtain a strong evaluation function.

---
Tags: engines, programming
---


# Question
Title: What is the maximum total number of piece points possible on the board?
Maximum number of non-pawn pieces on the board notes how to get the maximum number of non-pawn pieces on the board.

But what about the maximum number of points possible? It seems like this starts easily enough. For instance: 1. a4 b6 2. a5 Bb7 3. a6 h5 4. axb7 Nc6 5. b8=Q, with a plan of Ra1-a3-e3 to allow Black's a-pawn to queen.

The basic idea would be to have each side capture the other's 4 minor pieces, so that 1) the capturing pawn becomes passed and 2) it creates an opposing pawn become passed. Once the two pawns above have queened, White or Black could take bxa(1-8), Then cxb(1-8) and so forth.

This is the outline, but how do we create a legal game that satisfies this?

# Answer
> 5 votes
As Jeremy said, the maximum is indeed 182 points. Here is a proof game for it.

```
[FEN ""]
[startply "110"]

1. b4 g5 2. h4 a5 3. h5 a4 4. h6 a3 5. Bb2 Bg7 6. hxg7 axb2 7. a4 h5 8. a5 h4 9. a6 h3 10. Nf3 Nc6 11. b5 g4 12. b6 g3 13. Nh2 Na7 14. bxa7 gxh2 15. g4 b5 16. g5 b4 17. g6 b3 18. e4 d5 19. c4 f5 20. c5 f4 21. Bc4 Bf5 22. exf5 dxc4 23. Nc3 f3 24. Ne2 fxe2 25. f4 Kd7 26. Kf2 e5 27. f6 e4 28. f5 e3+ 29. Kf3 Kc6 30. f7 Kb5 31. c6 Nf6 32. g8=Q Nd7 33. cxd7 c5 34. f8=Q Qb6 35. g7 Re8 36. a8=Q c3 37. d4 c2 38. d5 c4 39. f6 c3 40. f7 e1=Q 41. d6 e2 42. d8=Q c1=Q 43. Rf1 h1=Q+ 44. Kg4 h2 45. Qb7 Qd5 46. a7 h1=Q 47. a8=Q Qf2 48. d7 b1=Q 49. Qfe7 b2 50. Qh7 Qba2 51. g8=Q b1=Q 52. f8=Q c2 53. Qdc7 Qcb2 54. d8=Q e1=Q 55. Rg1 c1=Q

```

# Answer
> 2 votes
I think you can get nine queens and two rooks for each side. Consider this: a4 b5; a5 Bg7; a6 b4; axb7 Nc6; b8(Q) Na5; Na3 bxa3; b4 a2; Rb1 a1(Q).

You have made two captures, promoted two pawns, and cleared the way for two more pawns to advance to the eighth rank. In other words, you can make it so that one pawn capture allows two pawns to queen.

The tools just need to get out of the way.

---
Tags: problems, records, pieces
---


title: Split pgn files by players

text:
# Question
Title: Split pgn files by players
Is there a way to split large PGN files into folders grouped by the players? For example, in a tournament, each player has several games in one file. I aim to group each game by players to the respective folders (one game, one file). So it will produce two files for each match, one for player 1 and one for player 2 in two separate folders.

# Answer
Either you may be able to do it in a DB manager (ChessBase...) or you'll need a bit of coding in Chess Query Language

---

Download and extract `cqli` (a modern rewrite of the original `cql` software) to the folder containing your pgn database

Create a `p1.cql` file, with the following content (this is an example for getting all Kasparov's games) :

```
cql(input database.pgn)

"Kasparov" in player

```

---

Open Powershell/Terminal (depending on your platform), `cd` to the database directory and run

Unix/Linux

```
./cqli --threads 8 p1.cql

```

macOS

```
# For Intel Macs
./cqli-x86_64 --threads 8 p1.cql
# For Apple Silicon Macs
./cqli-arm64 --threads 8 p1.cql

```

Windows

```
./cqli.exe --threads 8 p1.cql

```

---

And you'll find the resulting database in `p1-out.pgn`.

Note that it is a database, to extract it, we can use kentdjb `pgn-extract`

Unzip the windows executable in the database program as previously, or build it from source if you are on Linux/macOS

And then run :

```
./pgn-extract -\#1 p1-out.pgn

```

*The backslash before the `#` is essential*

This will split your pgn into files named `1.pgn`, `2.pgn`...
> 2 votes

---
Tags: pgn
---


# Question
Title: Ruy Lopez Main Line - Why not Be7 before Nf6?
In the Ruy Lopez, Morphy Defense Main Line,

```
[FEN ""]
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7

```

after 4.Ba4, the engine suggests Be7 as one of the best moves, tied with Nf6. The opening book Perfect2021 confirms this. Yet, there's no mention of this move order in any of the materials I've read so far, including the Wikipedia article and the Chess Opening Theory Wikibook chapter on the Morphy Defense. Lichess' Masters Database has only 132 games where 4...Be7 was played, out of 88,219 (0.15%). What am I missing? Why does no one play Be7 first?

# Answer
> 16 votes
Practically/psychologically Nf6 makes White's life a bit harder because it also leaves open the possibility of following up with Bc5 (I see that this is called the Møller defense). This kind of thing is part of why it's a general opening principle to develop Knights before Bishops: usually we know where the Knight goes (here, to f6) while the Bishop has a choice so we keep more options by moving the Knight first.

# Answer
> 9 votes
> Why does no one play Be7 first?

Because Nf6 is more forcing. It attacks the pawn on e4 forcing white to do something about the threat. Castles indirectly does this by opening the possibility of Re1 if black takes the e4 pawn.

# Answer
> 7 votes
5...Be7 will almost always transpose into 5...Nf6 followed by 6...Be7, so there's no special line to worry about. However after 5...Nf6 Black still has other options

We usually want to develop first the pieces that we know which squares will go to. The knight goes to f6 on almost every game in this line, but the bihsop can decide later between c5 and e7.

# Answer
> 1 votes
Nf6 puts pressure on e4 and is more flexible, since it still keeps the option of developing the bishop to c5 as well, as well as the possibility of playing the open defense after Nxe4 next move. Essentially, it makes white's life a bit harder when it comes to preparing for the game as they need to keep track of different variations, and maybe they are reluctant to enter a particular line against a certain type of player.

---
Tags: opening, ruy-lopez
---


# Question
Title: Black to play and win but why was the move played a blunder?
In the position below Minic just had to play one move to reach the time control and, in those days, the adjournment which would have given his team a chance to find the win. Unfortunately he blundered with Bd5 and the win was gone and the game was agreed drawn without resuming.

```
[fen ""]
[Title "Bellon - Minic, Siegen Olympiad 1970"]
[Startply "79"]

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bc4 e6 7.Bb3 b5 8.O-O Be7 9.f4 O-O 10.a3 Bb7 11.Qf3 Nbd7 12.Re1 Rc8 13.g4 Rxc3 14.bxc3 Nc5 15.g5 Nfxe4 16.Qh5 Qc8 17.Re3 g6 18.Qh3 e5 19.Qxc8 Rxc8 20.fxe5 dxe5 21.Nf3 Nxb3 22.cxb3 Bc5 23.Nxe5 Nxg5 24.Kf1 Bxe3 25.Bxe3 Ne6 26.c4 f6 27.Nd7 f5 28.c5 f4 29.Bf2 Rd8 30.Rd1 Bc6 31.Nf6+ Kf7 32.Rxd8 Nxd8 33.Nxh7 Ne6 34.h4 Kg7 35.Ng5 Nxg5 36.hxg5 Kf7 37.Bd4 Ke6 38.b4 Kd5 39.Bf6 Ke4 40.Kf2 Bd5 1/2-1/2

```

I could ask how does black win from the position after white's 40th move but you would all just plug the position into your engines. So, instead:

Why was Bd5 a blunder? How did it give his opponent a chance to save the draw.

**Hint**: This question is based on analysis by Artur Jusupov in a Chess24 video a few years ago. Freedom of movement is more important than material.

# Answer
Contrarily to all what was said here (including the deleted post), if Black can win, then with the immediate 1...a5! 2.bxa5 Kd3! Principle of different-color bishop endgames: you need two passers far away to "scissor" the opponent bishop. Note that a) the Bc6 holds the a- and c- pawn AND protects the f-passer (after f3), good boy and b) the bishop can't defend a3 since it doesn't reach b4 in time (assuming Pf3: Bc1 Kc2 Be3 Kb2). And Pf3 and Pb4 are too far apart.

But that's not the end of the story, as White can try 1...a5 2.Ke2 (now or never) f3+ 3.Kd2. Then Black wins with a4. The king penetrates via b3, as White can't bring the B to f2 in time AND block the bK out with Kc3. Timing is crucial in this endgame, I've got a hunch that already Ph6/Ph7 instead of Pg5/Pg6 saves White's hide.

Don't take this analysis for granted, I'm an endgame god :-) but alas, no engine (and used none). But even with one minute left, I would have played a5!
> 3 votes

---
Tags: analysis, endgame, puzzles
---


# Question
Title: I lose more than I won? And I can't stand it
I lose like almost 1700 games in rapid and it's bad and I feel like I'm going have a hemmorage because it's pissing me off and bad I am? is it because my intellectual disability or what?

# Answer
Your last post was from February 6th with 1000 games lost. This is not even a month. Lets assume, you lose around 50 % of the games, this means, in this 24 days you played 1400 games, which averages to around 58 games a day.

Lets say, you sleep 8 hours which leaves you with 16 hours non stop play time. Even then each game could have at maximum 16 minutes of play time per game, so the game format that you are playing is for sure less than a 10 minutes game.

But 16 hours of playing a day is rather unlikely, even 8 is hard to stay focused (and motivated if, as you say, you lose a lot).

So that leaves me with the conclusion, that, even though you claim you play rapid, you probably play at bullet or blitz speed and that is just a very bad choice for a beginner. You don't have the game intuition for that yet. At that speeds you can't calculate anymore and have to 'feel' which moves will be good and this you only get by calculating first a lot.

So my recommendation, the same as you will read it anywhere when some beginner asks how to get better, is, to slow down and play fewer games. At least 10 minutes thinking per side, better yet 15 or more. Only like this you will really have a time to calculate and get an understanding of the game. Also go over your games afterwards and see where you made your mistakes and try not to repeat that anymore. But don't lazily let the engine show you where you made mistakes, but try to find it yourself first.

Also, do a lot of puzzles. Like this you will see many different positions and think them through. But you have to try to achieve a success ratio of at least 60 % I would say. If you just look at it for a second, make random moves until you accidentally find the correct one you will not get anything out of them.
> 2 votes

---
Tags: computer-chess, losing
---


# Question
Title: Why is the outdated Steinitz Defense still so popular among non-professionals?
The Steinitz Defense is generally considered outdated by modern professional players. However, according to the Lichess Database, the move 3... d6 is actually the second most popular choice after 1.e4 e5 2.Nf3 Nc6 3.Bb5. (Among master games, 3... d6 is only the 8th most popular choice.)

I am wondering what makes the move 3... d6 popular among non-professionals. After all, this move has the reputation of being outdated, does not develop a piece, and appears passive.

# Answer
If it is called the Steinitz defence it cant be all that bad. Steinitz himself employed it because he wanted to keep as much pawn control over the center as he could, but as others have said, the resulting positions are a bit passive and not to the taste of modern grandmasters. It is playable by unsophisticated Black players because generally they only face unsophisticated White players who do not know how to exploit their small advantage.

The one piece of theory you really ought to know is the "Tarrasch trap" 1.e4 e5 2.Nf3 Nc6 3.Bb5 d6 4.d4 Bd7 5.Nc3 Be7 6.0-0 Nf6 7.Re1 0-0? 8.Bxc6! Bxc6 9.dxe5 dxe5 10.Qxd8 Raxd8 11.Nxe5 Bxe4 12.Nxe4 Nxe4 13.Nd3! f5 14 f3 Bc5+ 15.Nxc5 Nxc5 16.Bg5 Rd5 17.Be7 and wins because if 17. Re8/f7 then 18.c4! (Tarrasch-Marco, Dresden, 1896) This trap is theoretically important because it shows that Steinitz original plan of maintaining a pawn center cannot be achieved.

Amusingly, I once played in a tournament where 7..0-0? was played against a friend of mine. My friend was aware that this was an error that should lose at least a Pawn, but could not recall exactly how it went, just that it began by exchanging everything off. He was reluctant to do this, because if he did make all the exchanges, but still could not remember the final moves, he might only draw against a weak opponent. So after thinking for a very long time, he refrained from the exchanges but eventually lost on time.
> 2 votes

# Answer
The move 3... d6 is passive, but it is not completely unjustified. White's bishop on b5 threatens to trade itself for black's knight on c6, leaving black's e5 pawn undefended and capturable by white's knight. Although white can't actually take on e5 because of the Qd4 fork, most amateurs who aren't familiar with this line don't calculate this far ahead.
> 2 votes

# Answer
It is a solid option which is relatively easy to play since you do not need to memorize so many concrete variations as in the Berlin defense or in the Marshall gambit, for example.
> 1 votes

# Answer
Because they want to play Bg4 then Qf6 then Ne7 then Nf5.

Because they can avoid all white's tactics on e5, while still having their tactics on e4.

Because it will often transpose to the normal Morphy lines.

Those are some reasons that immediately come to mind.
> 0 votes

---
Tags: opening, statistics, 1.e4
---


# Question
Title: I accidentally lost my queen and I resign is that a bad thing to do?
If it's bad what should I do? And I why resigning after I lost my queen is bad? I have no way to win, and I and I have to resign because I am going to lose anyway. So is it bad?

```
[Event "tetrahedronx7 vs. MikeKettering"]
[Site "Chess.com"]
[Date "2023-02-24"]
[White "tetrahedronx7"]
[Black "MikeKettering"]
[Result "0-1"]
[WhiteElo "693"]
[BlackElo "825"]
[TimeControl "standard"]
[Termination "MikeKettering won by resignation"]
[FEN ""]
1. e4 e5 2. d4 exd4 3. Qxd4 Nc6 4. Qxg7 Bxg7 5. Be3 a6 6. Nd2 Bxb2 7. Rd1 Bc3 8.
Be2 Bxd2+ 9. Bxd2 f6 10. Nf3 h5 11. O-O Nh6 12. Nh4 Nf7 13. Ng6 Rg8 14. Nf4 d6
15. Nxh5 Bh3 16. Bf3 Bg4 17. Bxg4 Rxg4 18. Rde1 Nfe5 19. Bc3 Rh4 20. Ng7+ Kf7
21. Nf5 Rh7 22. Nd4 Ne7 23. Nf5 N7c6 24. Ng3 Nc4 25. Nf5 Qg8 0-1

```

# Answer
No. Resigning is a perfectly acceptable way to end a game of chess. In fact the vast majority of decisive games finish this way. You should not feel there is any stigma whatsoever associated with resigning in a lost position such as the one above.
> 6 votes

# Answer
Not resigning after losing your Queen is insulting to your opponent. Your are doubting their ability to finish off what should be a very simple task. But if both players are beginners, maybe that doubt is justified.

The best criterion is to ask yourself, "How will my opponent feel if I play on?" and if you think they will justifiably feel bored and insulted, then you should resign.
> 2 votes

---
Tags: strategy, online-chess, queens
---


# Question
Title: How to limit lines in scid vs pc in annotate mode?
I would like to reduce the number of lines calculated by the engine to speed up the analysis but I cannot find the appropriate option for that. Does anybody know how to do this in Scid vs PC?

# Answer
> 2 votes
In Scid vs PC, after you turn on an engine, a window with analysis opens. In that window you can see icons like **Stop Engine**, **Add Move**, **Add Variation** etc. (see picture below).

Among them, there is a small box with a number (marked by a red circle in the picture below), namely the number of lines suggested by the engine. Adjust that according to your preference. If I understood your question correctly, that should solve your problem. Just for the sake of completeness, I have the version 4.13 of Scid vs PC.

# Answer
> 0 votes
The keyword you're looking for is variations. To save this for future use, make a new analysis engine.

Under Tools, click either Analysis Engine or Analysis Engine #2:

Click New...:

Fill in the fields and hit Configure UCI engine:

Now you can set the Multiple variations variable to any amount of 'lines' you want:

Don't forget to look at all the other nifty variables you come across :-)

This sets the same number as Zvonimir indicated in their answer, but now it can be saved as a standard setting. If you want to use it again, just select the correct engine.

---
Tags: analysis, scid
---


# Question
Title: Does the Russian Chess Federation switching to the ACF actually make it harder for Chinese/Indian players to qualify for the World Championships?
Source

> "Thirdly, it is quite surprising that Indian and the Chinese federations agreed to this switch by the CFR, if they have (I have not seen the results of the vote), because it will lead to increased competition and therefore reduced opportunities for their players to qualify for places in the World Championship cycle, unless changes are made to it.

Does increased competition in this way actually make it harder for Indian & Chinese players to qualify for the World Championship, or should it be easier (since playing against strong competition is a necessary condition to becoming a strong player)?

If it does make it harder, how?

# Answer
> 3 votes
The Russian Chess Federation's move from Europe (ECU) to Asia (ACF) takes effect on 1st May. In the meantime players with RUS membership may not play FIDE rated chess. Those Russian players who have transferred to FID as Russians are eligible to play in European championship competitions until that date.

So, the European Individual Chess Championship, which start today, March 3, in Vrnjacka Banja, Serbia already has 48 players registered under the FIDE flag.

However, FIDE has introduced new rules for players wishing to change federation to country member federations (i.e. not FID). According to this chess.com article:

> Normally speaking, a federation accepting a new player has to pay a 5,000-euro transfer fee to FIDE. However, much more significant is the "compensation fee" that the Russian federation would receive if a player leaves. For players rated 2700 and above, that is as high as 50,000 euros; for players rated 2600 to 2699, it's 30,000 euros.

The FIDE Council decided that all transfer and compensation fees due to the CFR are waived for players registered there. They have until August 31, 2023, to decide on a transfer to one of the ECU's member federations and will have the right to represent the new federation in all official individual events of FIDE from the next day of submitting their application without any restrictions, provided that all other conditions for the transfer have been met besides paying the fees.

The article goes on to claim that players are better off playing in European competitions than Asian:

> After the CFR leaves the ECU, these players will lose some of the benefits they have in Europe, such as participating in the different European championships. **According to ECU President Zurab Azmaiparashvili, the ACF is "several years behind" the ECU in terms of structure and opportunities for players: "As part of the ECU, it will be an easier life, also for trainers," he told Chess.com.**

The first Russian player to take advantage of this (that I have seen) is Alexandra Kosteniuk who announced in a tweet today:

> Now it’s official. Representing Switzerland since 03-03-2023

So, I suspect that in the long run the answer to your question is that it will make little or no difference for the simple reason that FIDE have made it possible for Russian players to move cost-free and without delays to the European federation of their choice and most are likely to do so.

---
Tags: learning, fide, world-championship
---


title: Chess puzzles and gnuchess/xboard

text:
# Question
Title: Chess puzzles and gnuchess/xboard
Just come back to chess after a long pause. I want to set up a position -- a simple one -- and then have gnuchess reply to my moves as I try for a mate. But, with a simple Q+K against K alone, gnuchess resigns after one move and I'd like it to play on. Can I persuade it to do this?

# Answer
Try increasing the ResignScore option

Options

```
ResignScore
Default: 600

This is the score in centipawns that will trigger resign "counting".

```
> 2 votes

---
Tags: engines
---


title: How do I create endgame tablebases?

text:
# Question
Title: How do I create endgame tablebases?
What software can I use to create and verify endgame databases? I want to create my own tablebases from scratch on my PC - I'm specifically looking for open-source software that I can modify to support variants.

# Answer
I have used syzygy1/tb to create and verify tablebases. Never tried to modify it so not sure how easy that is.
> 3 votes

---
Tags: endgame, software, tablebases
---


# Question
Title: How would I detect dead position in a tablebase?
I am programming a tablebase for fairy chess, and would like to conclude the game if mate cannot be reached in any way. I guess this has to be detected when the evaluation (win in... / loss in... / draw) is created. So far, my (working) algorithm for evaluating winnable positions looks like this in pseudocode:

* Start with all mate positions and evaluate them
* For each position which has changed evaluation, make one move backwards
* Evaluate the resulting positions by checking all forward moves and pick the best result (unexplored = draw)
* If the "best" result has changed, add the position to the queue for next iteration
* Return to (2)

```
activePositions = findAllMatePositions()
for(ap in activePositions) ap.result=[Loss,0]
while(activePositions not empty)
{
 newActivePositions = []
 for (ap in activePositions)
 {
   for(backmove in ap.getBackMoves())
   {
     newPosition = ap.makeBackMove(backmove)
     for(move in newPosition.getMoves())
     {
      // find the best move and evaluation of resulting position
     }
     if(/*result of newPosition has changed */) newActivePositions.push(newPosition)
     ap.undoBackMove(backmove)
   }
  }
  activePositions = newActivePositions
}

```

Ideally, I would like for the dead position be detected during the main evaluation, but I guess I would need to run it again. Basically the issues are:

* Where to start? Should I need to pick all positions which were not evaluated with win or loss, for the first iteration?
* Would it be easier if I first went for white cannot lose / black cannot lose detection?

Edit: So to determine draw by both sides, it is rather easy:

* Mark all drawn positions as dead candidates
* For each position, if any of the moves does not lead to dead position candidates, remove it from the candidates as well
* Continue until no candidates are removed in each iteration

So now only remains (the harder, but not as useful for me) solution how to determine this for a player individually (cannot be helpmated by the other player, but can mate the opponent).

# Answer
You *might* be computationally better off if you "hotwire" the problem. Consider an orthodox tablebase:

* Death 1: KB/K, KN/K. Trivial detection.
* Death 2: Forced stalemate. Can be detected by playing just a few forward iterations.
* Death 3: Pawn barricade. Needs 8 men.

I.e., a nonissue in orthodox chess, tricky cases have more men than your usual tablebase.

Depending on the fairy condition, this can become less trivial (imagine KLi/KLi - there *is* one mate position, but it can't be reached even with help play - KP/KLi with lion promotion is the only way).
> 1 votes

# Answer
I am not exactly sure what is the question you are asking.

However, if I were to build a tablebase for fairy conditions or pieces, I would proceed as follows. Note that the solution implies that the tablebase is *closed*, meaning that performing a legal move from any position in the tablebase yields a position which is also in the tablebase.

```
queue = []

foreach position in tablebase:
  if is_mate(position):
    position.store_tablebase_info(mate=...)
    queue.push_back(position)

while queue not empty:
  position = queue.pop_front()
  foreach move in position.list_backward_moves():
    new_position = position.play_backward(move)
    if not new_position.has_tablebase_info():
      new_position.store_tablebase_info(winning=...)
      queue.push_back(new_position)

foreach position in tablebase:
  if not position.has_tablebase_info():
    position.store_tablebase_info(drawn=true)

```

Using this simple algorithm, you do not have to introduce heuristics to determine which positions are drawn, as this can be difficult for some fairy conditions.

Note that position are handled by "distance to mate", as we initialize the queue with mate positions, then end up adding positions with a distance to mate equal to 1, then those with distance equal to 2, etc.

Hopefully this helps!
> 1 votes

---
Tags: software, tablebases, retrograde-analysis, dead-position
---


# Question
Title: What's the point of 4.a4 in this Czech Benoni?
In the following Benoni position (White to move):

```
rnbqkbnr/pp3ppp/3p4/2pPp3/8/2N5/PPP1PPPP/R1BQKBNR w KQkq e6 0 4

```

The engine's (Lichess' Stockfish) first move, and also the one with best results (although very few games) in Lichess, is 4.a4. What's the purpose of that move? I can understand playing a4 when Black plays ...a6, to prevent b5, or when White has played Bb5 and Black replies ...Bd7, but playing 4.a4 seems premature to me.

# Answer
White is pretty sure they'll have to play a4 at some point, while the rest of the pieces don't have a certain square yet.

The statistics don't mean too much by themselves as we need to take transpositions into account. For instance, White could go 4.Nf3 now (the g1 knight will most certainly go for Nf3-Nd2-Nc4) and play a4 soon after reaching the same positions.
> 1 votes

---
Tags: pawns, pawn-structure, benoni
---


# Question
Title: Longest sequence of unique legal moves for one player, always in check and ending in checkmate
I recently played a bullet game, in which I thought I was in checkmate, but then realized I had one legal move, this then repeated again and again 6 times until ultimately I was in checkmate. I share this anecdote as an explanation for the seemingly arbitrary parameters.

To reiterate, one player (black or white) puts the other player in check. That player has only one legal move (moving the king, blocking the check, or capturing the attacking piece) Then the other player puts them in the same circumstance of one legal move. Player one does not need to be put in check or have their moves limited, only in the sense that no positions may be repeated.

The final check of the sequence is checkmate.

# Answer
Here is such a sequence of **627 moves**. With some trickery utilizing captures, each position is indeed unique. Many thanks goes to @Noam D. Elkies for suggesting improvements.

```
[Title "me, chess.stack.exchange.com, 3/7/2023"]
[FEN "8/8/8/pp1NN3/1p1KN3/1p6/nnppp1R1/1b3Qbk w - - 0 1"]

1. Rxg1+ Kh2 2. Qf2+ Kh3 3. Rg3+ Kh4 4. Qf4+ Kh5 5. Rg5+ Kh6 6. Qf6+ Kh7 7. Rg7+ Kh8 8. Rf7+ Kg8 9. Qg5+ Kh8 10. Qh4+ Kg8 11. Qg3+ Kh8 12. Qh2+ Kg8 13. Qg1+ Kh8 14. Qh1+ Kg8 15. Qg2+ Kh8 16. Qh3+ Kg8 17. Qg4+ Kh8 18. Qh5+ Kg8 19. Qg6+ Kh8 20. Qh6+ Kg8 21. Rg7+ Kf8 22. Qf6+ Ke8 23. Re7+ Kd8 24.Qd6+ Kc8 25. Rc7+ Kb8 26. Qb6+ Ka8 27. Qxa5+ Kb8 28. Qb6+ Ka8 29. Qa6+ Kb8 30. Rb7+ Kc8 31. Qc6+ Kd8 32. Rd7+ Ke8 33. Qe6+ Kf8 34. Rf7+ Kg8 35. Qg6+ Kh8 36. Qh5+ Kg8 37. Qg4+ Kh8 38. Qh3+ Kg8 39. Qg2+ Kh8 40. Qh1+ Kg8 41. Qg1+ Kh8 42. Qh2+ Kg8 43. Qg3+ Kh8 44. Qh4+ Kg8 45. Qg5+ Kh8 46. Qf6+ Kg8 47. Rg7+ Kh8 48. Rg6+ Kh7 49. Qf7+ Kh8 50. Qe8+ Kh7 51. Qd7+ Kh8 52. Qc8+ Kh7 53. Qb7+ Kh8 54. Qa8+ Kh7 55. Qa7+ Kh8 56. Qb8+ Kh7 57. Qc7+ Kh8 58. Qd8+ Kh7 59. Qe7+ Kh8 60. Qf8+ Kh7 61. Rg7+ Kh6 62. Qf6+ Kh5 63. Rg5+ Kh4 64. Qf4+ Kh3 65. Rg3+ Kh2 66. Qf2+ Kh1 67. Qf3+ Kh2 68. Rg2+ Kh1 69. Rxe2+ Kg1 70. Rg2+ Kh1 71. Rg3+ Kh2 72. Qf2+ Kh1 73. Qf1+ Kh2 74. Rg2+ Kh3 75. Qf3+ Kh4 76. Rg4+ Kh5 77. Qf5+ Kh6 78. Rg6+ Kh7 79. Qf7+ Kh8 80. Qe8+ Kh7 81. Qd7+ Kh8 82. Qc8+ Kh7 83. Qb7+ Kh8 84. Qa8+ Kh7 85. Qa7+ Kh8 86. Qb8+ Kh7 87. Qc7+ Kh8 88. Qd8+ Kh7 89. Qe7+ Kh8 90. Qf6+ Kh7 91. Rg7+ Kh8 92. Rf7+ Kg8 93. Qg6+ Kh8 94. Qh5+ Kg8 95. Qg4+ Kh8 96. Qh3+ Kg8 97. Qg2+ Kh8 98. Qh1+ Kg8 99. Qg1+ Kh8 100. Qh2+ Kg8 101. Qg3+ Kh8 102. Qh4+ Kg8 103. Qg5+ Kh8 104. Qh6+ Kg8 105. Rg7+ Kf8 106. Qf6+ Ke8 107. Re7+ Kd8 108. Qd6+ Kc8 109. Rc7+ Kb8 110. Qb6+ Ka8 111. Qc6+ Kb8 112. Rb7+ Ka8 113. Rxb5+ Ka7 114. Rb7+ Ka8 115. Rc7+ Kb8 116. Qb6+ Ka8 117. Qa5+ Kb8 118. Qb5+ Ka8 119. Qa6+ Kb8 120. Rb7+ Kc8 121. Qc6+ Kd8 122. Rd7+ Ke8 123. Qe6+ Kf8 124. Rf7+ Kg8 125. Qg6+ Kh8 126. Qh5+ Kg8 127. Qg4+ Kh8 128. Qh3+ Kg8 129. Qg2+ Kh8 130. Qh1+ Kg8 131. Qg1+ Kh8 132. Qh2+ Kg8 133. Qg3+ Kh8 134. Qh4+ Kg8 135. Qg5+ Kh8 136. Qf6+ Kg8 137. Rg7+ Kh8 138. Rg6+ Kh7 139. Qf7+ Kh8 140. Qe8+ Kh7 141. Qd7+ Kh8 142. Qc8+ Kh7 143. Qb7+ Kh8 144. Qa8+ Kh7 145. Qa7+ Kh8 146. Qb8+ Kh7 147. Qc7+ Kh8 148. Qd8+ Kh7 149. Qe7+ Kh8 150. Qf8+ Kh7 151. Rg7+ Kh6 152. Qf6+ Kh5 153. Rg5+ Kh4 154. Qf4+ Kh3 155. Rg3+ Kh2 156. Qf2+ Kh1 157. Qf3+ Kh2 158. Rg2+ Kh1 159. Rxd2+ Kg1 160. Rg2+ Kh1 161. Rg3+ Kh2 162. Qf2+ Kh1 163. Qe1+ Kh2 164. Qe2+ Kh1 165. Qf1+ Kh2 166. Rg2+ Kh3 167. Qf3+ Kh4 168. Rg4+ Kh5 169. Qf5+ Kh6 170. Rg6+ Kh7 171. Qf7+ Kh8 172. Qf6+ Kh7 173. Rg7+ Kh8 174. Rf7+ Kg8 175. Qg6+ Kh8 176. Qh5+ Kg8 177. Qg4+ Kh8 178. Qh3+ Kg8 179. Qg2+ Kh8 180. Qh1+ Kg8 181. Qg1+ Kh8 182. Qh2+ Kg8 183. Qg3+ Kh8 184. Qh4+ Kg8 185. Qg5+ Kh8 186. Qh6+ Kg8 187. Rg7+ Kf8 188. Qf6+ Ke8 189. Re7+ Kd8 190. Qd6+ Kc8 191. Rc7+ Kb8 192. Qb6+ Ka8 193. Qc6+ Kb8 194. Rb7+ Ka8 195. Rxb4+ Ka7 196. Rb7+ Ka8 197. Rc7+ Kb8 198. Qb6+ Ka8 199. Qa5+ Kb8 200. Qb5+ Ka8 201. Qa6+ Kb8 202. Rb7+ Kc8 203. Qc6+ Kd8 204. Rd7+ Ke8 205. Qe6+ Kf8 206. Rf7+ Kg8 207. Qg6+ Kh8 208. Qh5+ Kg8 209. Qg4+ Kh8 210. Qh3+ Kg8 211. Qg2+ Kh8 212. Qh1+ Kg8 213. Qg1+ Kh8 214. Qh2+ Kg8 215. Qg3+ Kh8 216. Qh4+ Kg8 217. Qg5+ Kh8 218. Qf6+ Kg8 219. Rg7+ Kh8 220. Rg6+ Kh7 221. Qf7+ Kh8 222. Qe8+ Kh7 223. Qd7+ Kh8 224. Qc8+ Kh7 225. Qb7+ Kh8 226. Qa8+ Kh7 227. Qa7+ Kh8 228. Qb8+ Kh7 229. Qc7+ Kh8 230. Qd8+ Kh7 231. Qe7+ Kh8 232. Qf8+ Kh7 233. Rg7+ Kh6 234. Qf6+ Kh5 235. Rg5+ Kh4 236. Qf4+ Kh3 237. Rg3+ Kh2 238. Qf2+ Kh1 239. Qf3+ Kh2 240. Rg2+ Kh1 241. Rxc2+ Kg1 242. Rg2+ Kh1 243. Rg3+ Kh2 244. Qf2+ Kh1 245. Qe1+ Kh2 246. Qe2+ Kh1 247. Qf1+ Kh2 248. Rg2+ Kh3 249. Qf3+ Kh4 250. Rg4+ Kh5 251. Qf5+ Kh6 252. Rg6+ Kh7 253. Qf7+ Kh8 254. Qe8+ Kh7 255. Qd7+ Kh8 256. Qc8+ Kh7 257. Qb7+ Kh8 258. Qa8+ Kh7 259. Qa7+ Kh8 260. Qb8+ Kh7 261. Qc7+ Kh8 262. Qd8+ Kh7 263. Qe7+ Kh8 264. Qf8+ Kh7 265. Rg7+ Kh6 266. Qf6+ Kh5 267. Rg5+ Kh4 268. Qf4+ Kh3 269. Rg3+ Kh2 270. Qf2+ Kh1 271. Qf3+ Kh2 272. Rg2+ Kh1 273. Rxb2+ Kg1 274. Rg2+ Kh1 275. Rg3+ Kh2 276. Qf2+ Kh1 277. Qe1+ Kh2 278. Qd2+ Kh1 279. Qd1+ Kh2 280. Qe2+ Kh1 281. Qf1+ Kh2 282. Rg2+ Kh3 283. Qf3+ Kh4 284. Rg4+ Kh5 285. Qf5+ Kh6 286. Rg6+ Kh7 287. Qf7+ Kh8 288. Qf6+ Kh7 289. Rg7+ Kh8 290. Rf7+ Kg8 291. Qg5+ Kh8 292. Qh4+ Kg8 293. Qg3+ Kh8 294. Qh2+ Kg8 295. Qg1+ Kh8 296. Qh1+ Kg8 297. Qg2+ Kh8 298. Qh3+ Kg8 299. Qg4+ Kh8 300. Qh5+ Kg8 301. Qg6+ Kh8 302. Qh6+ Kg8 303. Rg7+ Kf8 304. Qf6+ Ke8 305. Re7+ Kd8 306. Qd6+ Kc8 307. Rc7+ Kb8 308. Qb6+ Ka8 309. Qc6+ Kb8 310. Rb7+ Ka8 311. Rxb3+ Ka7 312. Rb7+ Ka8 313. Rc7+ Kb8 314. Qb6+ Ka8 315. Qa5+ Kb8 316. Qb5+ Ka8 317. Qa6+ Kb8 318. Rb7+ Kc8 319. Qc6+ Kd8 320. Rd7+ Ke8 321. Qe6+ Kf8 322. Rf7+ Kg8 323. Qg6+ Kh8 324. Qf6+ Kg8 325. Rg7+ Kh8 326. Rg6+ Kh7 327. Qf7+ Kh8 328. Qe8+ Kh7 329. Qd7+ Kh8 330. Qc8+ Kh7 331. Qb7+ Kh8 332. Qa8+ Kh7 333. Qa7+ Kh8 334. Qb8+ Kh7 335. Qc7+ Kh8 336. Qd8+ Kh7 337. Qe7+ Kh8 338. Qf8+ Kh7 339. Rg7+ Kh6 340. Qf6+ Kh5 341. Rg5+ Kh4 342. Qf4+ Kh3 343. Rg3+ Kh2 344. Qf2+ Kh1 345. Qf3+ Kh2 346. Rg2+ Kh1 347. Rxa2+ Kg1 348. Rg2+ Kh1 349. Rg3+ Kh2 350. Qf2+ Kh1 351. Qe1+ Kh2 352. Qd2+ Kh1 353. Qd1+ Kh2 354. Qe2+ Kh1 355. Qf1+ Kh2 356. Rg2+ Kh3 357. Qf3+ Kh4 358. Rg4+ Kh5 359. Qf5+ Kh6 360. Rg6+ Kh7 361. Qf7+ Kh8 362. Qf6+ Kh7 363. Rg7+ Kh8 364. Rf7+ Kg8 365. Qg6+ Kh8 366. Qh5+ Kg8 367. Qg4+ Kh8 368. Qh3+ Kg8 369. Qg2+ Kh8 370. Qh1+ Kg8 371. Qg1+ Kh8 372. Qh2+ Kg8 373. Qg3+ Kh8 374. Qh4+ Kg8 375. Qg5+ Kh8 376. Qh6+ Kg8 377. Rg7+ Kf8 378. Qf6+ Ke8 379. Re7+ Kd8 380. Qd6+ Kc8 381. Rc7+ Kb8 382. Qb6+ Ka8 383. Qa5+ Kb8 384. Qb4+ Ka8 385. Qa3+ Kb8 386. Qb3+ Ka8 387. Qa4+ Kb8 388. Qb5+ Ka8 389. Qa6+ Kb8 390. Qb6+ Ka8 391. Qc6+ Kb8 392. Rb7+ Ka8 393. Rxb1+ Ka7 394. Rb7+ Ka8 395. Rc7+ Kb8 396. Qb6+ Ka8 397. Qa5+ Kb8 398. Qb4+ Ka8 399. Qa3+ Kb8 400. Qb2+ Ka8 401. Qa1+ Kb8 402. Qb1+ Ka8 403. Qa2+ Kb8 404. Qb3+ Ka8 405. Qa4+ Kb8 406. Qb5+ Ka8 407. Qa6+ Kb8 408. Rb7+ Kc8 409. Qc6+ Kd8 410. Rd7+ Ke8 411. Qe6+ Kf8 412. Rf7+ Kg8 413. Qg6+ Kh8 414. Qf6+ Kg8 415. Rg7+ Kh8 416. Rg6+ Kh7 417. Qf7+ Kh8 418. Qe8+ Kh7 419. Qd7+ Kh8 420. Qc8+ Kh7 421. Qb7+ Kh8 422. Qa8+ Kh7 423. Qa7+ Kh8 424. Qb8+ Kh7 425. Qc7+ Kh8 426. Qd8+ Kh7 427. Qe7+ Kh8 428. Qf8+ Kh7 429. Rg7+ Kh6 430. Qf6+ Kh5 431. Rg5+ Kh4 432. Qf4+ Kh3 433. Rg3+ Kh2 434. Qf2+ Kh1 435. Qf3+ Kh2 436. Qf2+ Kh1 437. Qe1+ Kh2 438. Qd2+ Kh1 439. Qc1+ Kh2 440. Qb2+ Kh1 441. Qa1+ Kh2 442. Qa2+ Kh1 443. Qb1+ Kh2 444. Qc2+ Kh1 445. Qd1+ Kh2 446. Qe2+ Kh1 447. Qf3+ Kh2 448. Rg2+ Kh1 449. Rf2+ Kg1 450. Qg4+ Kh1 451. Qh5+ Kg1 452. Qg6+ Kh1 453. Qh7+ Kg1 454. Qg8+ Kh1 455. Qh8+ Kg1 456. Qg7+ Kh1 457. Qh6+ Kg1 458. Qg5+ Kh1 459. Ng3+ Kg1 460. Nh1+ Kxh1 461. Qh4+ Kg1 462. Qg3+ Kh1 463. Qh3+ Kg1 464. Rg2+ Kf1 465. Qf3+ Ke1 466. Re2+ Kd1 467. Qd3+ Kc1 468. Rc2+ Kb1 469. Qb3+ Ka1 470. Qc3+ Kb1 471. Rb2+ Ka1 472. Rb3+ Ka2 473. Qc2+ Ka1 474. Qc1+ Ka2 475. Rb2+ Ka3 476. Qc3+ Ka4 477. Rb4+ Ka5 478. Qc5+ Ka6 479. Rb6+ Ka7 480. Qc7+ Ka8 481. Qd8+ Ka7 482. Qe7+ Ka8 483. Qf8+ Ka7 484. Qg7+ Ka8 485. Qh8+ Ka7 486. Qh7+ Ka8 487. Qg8+ Ka7 488. Qf7+ Ka8 489. Qe8+ Ka7 490. Qd7+ Ka8 491. Qc6+ Ka7 492. Rb7+ Ka8 493. Rc7+ Kb8 494. Qb6+ Ka8 495. Qa5+ Kb8 496. Qb4+ Ka8 497. Qa3+ Kb8 498. Qb2+ Ka8 499. Qa1+ Kb8 500. Qb1+ Ka8 501. Qa2+ Kb8 502. Qb3+ Ka8 503. Qa4+ Kb8 504. Qb5+ Ka8 505. Qa6+ Kb8 506. Rb7+ Kc8 507. Qc6+ Kd8 508. Rd7+ Ke8 509. Qe6+ Kf8 510. Rf7+ Kg8 511. Qg6+ Kh8 512. Qh5+ Kg8 513. Qg4+ Kh8 514. Qh3+ Kg8 515. Qg2+ Kh8 516. Qh1+ Kg8 517. Qg1+ Kh8 518. Qh2+ Kg8 519. Qg3+ Kh8 520. Qh4+ Kg8 521. Qg5+ Kh8 522. Ng6+ Kg8 523. Nh8+ Kxh8 524. Qf6+ Kg8 525. Rg7+ Kh8 526. Rg6+ Kh7 527. Qf7+ Kh8 528. Qf8+ Kh7 529. Rg7+ Kh6 530. Qf6+ Kh5 531. Rg5+ Kh4 532. Qf4+ Kh3 533. Rg3+ Kh2 534. Qf2+ Kh1 535. Qf3+ Kh2 536. Rg2+ Kh1 537. Rf2+ Kg1 538. Qg3+ Kh1 539. Qh3+ Kg1 540. Rg2+ Kf1 541. Qf3+ Ke1 542. Re2+ Kd1 543. Qd3+ Kc1 544. Rc2+ Kb1 545. Qb3+ Ka1 546. Qc3+ Kb1 547. Rb2+ Ka1 548. Rb3+ Ka2 549. Qc2+ Ka1 550. Qc1+ Ka2 551. Rb2+ Ka3 552. Qc3+ Ka4 553. Rb4+ Ka5 554. Qc5+ Ka6 555. Rb6+ Ka7 556. Qc7+ Ka8 557. Qd8+ Ka7 558. Qe7+ Ka8 559. Qf8+ Ka7 560. Qg7+ Ka8 561. Qh8+ Ka7 562. Qh7+ Ka8 563. Qg8+ Ka7 564. Qf7+ Ka8 565. Qe8+ Ka7 566. Qd7+ Ka8 567. Nc7+ Ka7 568. Na8+ Kxa8 569. Qc6+ Ka7 570. Rb7+ Ka8 571. Rc7+ Kb8 572. Qb6+ Ka8 573. Qa6+ Kb8 574. Rb7+ Kc8 575. Qc6+ Kd8 576. Rd7+ Ke8 577. Qe6+ Kf8 578. Rf7+ Kg8 579. Qg6+ Kh8 580. Qf6+ Kg8 581. Rg7+ Kh8 582. Rg6+ Kh7 583. Qf7+ Kh8 584. Qf8+ Kh7 585. Rg7+ Kh6 586. Qf6+ Kh5 587. Rg5+ Kh4 588. Qf4+ Kh3 589. Rg3+ Kh2 590. Qf2+ Kh1 591. Qf3+ Kh2 592. Rg2+ Kh1 593. Rf2+ Kg1 594. Qg3+ Kh1 595. Qh3+ Kg1 596. Rg2+ Kf1 597. Qf3+ Ke1 598. Re2+ Kd1 599. Qd3+ Kc1 600. Rc2+ Kb1 601. Qb3+ Ka1 602. Qc3+ Kb1 603. Rb2+ Ka1 604. Rb3+ Ka2 605. Qc2+ Ka1 606. Qc1+ Ka2 607. Rb2+ Ka3 608. Qc3+ Ka4 609. Rb4+ Ka5 610. Qc5+ Ka6 611. Rb6+ Ka7 612. Qc7+ Ka8 613. Qc6+ Ka7 614. Ra6+ Kb8 615. Qb6+ Kc8 616. Ra8+ Kd7 617. Rd8+ Ke7 618. Qd6+ Kf7 619. Rf8+ Kg7 620. Qf6+ Kh7 621. Qh8+ Kg6 622. Rf6+ Kg5 623. Qh6+ Kg4 624. Rf4+ Kg3 625. Qh4+ Kg2 626. Rf2+ Kg1 627. Qh2#

```
> 7 votes

---
Tags: problems, checkmate, records, check, forced-move
---


# Question
Title: Why are such complicated time controls popular?
In professional chess, I often see oddly arcane time controls. For instance, in the 2021 WCC

> each game was 120 minutes per side for the first 40 moves, 60 minutes for the next 20 moves, and 15 minutes for the rest of the game, with a 30-second increment per move starting with move 61. — Wikipedia

I have the impression that, in some of these games, the players even play rather pointless moves when close to the next time bonus in order to get it more quickly. Are there arguments against using just an initial amount of time with a fixed increment after each move (as it's often the case online)?

I really do not want to incite a religious crusade about time controls, I'm just a beginner wanting to understand the advantages of these complicated rules.

# Answer
> Why are such complicated time controls popular? ... For instance, in the 2021 WCC

First point, such time controls are neither popular nor unpopular with the vast majority of chess players for the simple reason that we never experience them. "WCC" stands for "World Chess Championship". Only two players ever play that once every two years. In general the time controls you talk about are only experienced at the very top of the game by the small number of players who can actually make a full time living at the game.

Secondly, the time control you quote has a total playing time for the game of 6 hours 30 minutes plus 1 minute per move after move 60. That is a very long time to be playing one game of chess with no breaks. Yes, the players are allowed to go to the bathroom during that time and they are usually allowed to also drink while playing but eating at the board is not allowed.

The intermediate time controls provide natural break points during the game which allow the players to have a break, go to the bathroom, splash some water on their face to freshen up, grab a sandwich, etc. It is very clear why they are popular at the elite levels where players can be playing one game for 7 hours or more.

At the more mundane level that the vast majority of us play at the time control is 90+30, 90 minutes for the game plus a 30 second increment from move 1, so for most games 4 hours or less. We normal players do very occasionally go beyond 60 moves but it is rare compared to the top players. We can get by with no intermediate time controls.
> 24 votes

# Answer
Part of it will be tradition. Note that for the example that you give, adding a time per move is only one done after move 60. Traditionally, it was not done at all for a very simple reason: It would not have been possible with the chess clocks at the time. Only the advent of digital chess clocks brought these new options.

In the example that you give, for the first section there are 3 minutes per move, which is a common choice for "serious" games. The second section is again 3 minutes per game. Also, it is exactly one hour, which means that with an analog clock there would have been no adjustment necessary after move 40 (as it would have been for example if it would have been 30 minutes).

Nevertheless, the time control for World Chess Championships varied. I just browsed Wikipedia a bit. For 1990 I found an even longer 2.5h for 40 moves (after which the game would be adjourned) and then 1h for every 16 moves. You will note that the additions are again full hours, but also that the time was even more than 3 minutes per move, which is fitting because after all a World Championship is more than serious ;)

Note: Someone with actual historical knowledge will certainly be able to correct some things above or give a more complete picture. I am no expert, but I played a bit of tournament chess before the adoption of digital chess clocks.
> 10 votes

# Answer
Old chess clocks didn't allow for increment to be added after every move, so extra time would be awarded at certain fixed points (normally moves 40 and 60).

With the invention of digital chess clocks time controls with increment per move have appeared and become more popular, but they're still not the only option being used.
> 1 votes

# Answer
To take only the "simple" time control as 1 hour after 40 moves, it is in my opinion to move the game to the "technical" phase. Middle game is over usually due to that part and so a player has gained the advantage.

It would be rather disappointing to be a piece up and yet lose because you have only 2 minutes. Of course, the argument can be "bad time management", but at least the modern FIDE rules have state that if you have decisive advantage or clear draw, then you can call the arbiter for a draw.

If the game is still unclear after the 40 moves, then the player who saved the time will still keep their time advantage.
> 0 votes

# Answer
On one hand, you have to have time controls for a number of reasons. There are logistical issues. Like you can't rent a venue out indefinitely. Also players might drag games out to get an unfair advantage like to wear an opponent down or to get to an adjournment where they can cheat. Also, people get bored and multi-day games aren't going to bring new fans into chess.

But on the other hand, you want to have good quality games and games that people can still appreciate centuries from now. You don't want the time controls to be too restrictive. It would be terrible if two players are playing an incredible game and the game ends because one player blunders in time trouble.

So, I think the goal is to keep the game moving and finish it, but still give the players enough time to produce a quality game.
> -2 votes

---
Tags: world-championship, time-control
---


title: Chess book reviews

text:
# Question
Title: Chess book reviews
What are some of the useful chess book review websites or YouTube channels out there? Or even people with chess blogs or Youtube channels which occasionally post book reviews.

# Answer
> 4 votes
The two web chess review sites I'm familiar with are John Watson's reviews for TWIC (The Week in Chess) and the book review section of Grand Master Square.

# Answer
> 3 votes
The Perpetual Chess Podcast has an entire Book Review Series with an organized listing of books reviewed.

Coverage includes over 30 books, including a wide variety of book types (tournament books, game collections, tactics, strategy, improvement).

Here's a partial list:

# Answer
> 0 votes
Jeremy Silman's website contains many chess book reviews:

https://www.jeremysilman.com/

---
Tags: books
---


title: Hourglass chess timer

text:
# Question
Title: Hourglass chess timer
Consider the following time control idea (which obviously would not be implemented with a sand clock, but a modern electronic clock): The hourglass starts in neutral, each move reverses it. Thus any of your pondering automatically adds to the time of the opponent. As soon as the last sand grain has fallen, loss on time.

Has such a time control been tried in a "serious" game or even tournament?

# Answer
The biggest *problem* with this variant, is that it gets players to play even more impulsively(the clock becomes a strategy to win). Imagine a scenario where white has accumulated a lot of time while black has very little time, instead of thinking hard to find the best move, white would much rather play quickly(otherwise black would gain time). In normal chess you can not control your opponents clock, in this variant you can. So the game becomes more about the clock than chess.

This is likely why it is mostly unknown, and not played OTB.
> 4 votes

---
Tags: chess-variants, time-control, chess-clocks
---


title: How to Learn Chess Comprehensively

text:
# Question
Title: How to Learn Chess Comprehensively
I'm a pretty new to playing chess - I understand the fundamentals and can implement some of the basic ideas like forks and pins, but have never properly learned how to play. I'm looking for a comprehensive way of learning - when I look for courses online, they pretty much all seem to cover individual aspects of the game like tactics or openings or other things like that. There seem to be some books that are comprehensive although I'm looking for something interactive.

What would you recommend? Is chess the sort of thing for which there exists a full course of 'everything you can know', or is it in fact best approached by just learning random things here and there from practice?

# Answer
> 5 votes
The "Chess Steps" method is the training method used by chess clubs for youth players in the Netherlands.

It starts at beginner level, the last step (6) is for players of roughly 2000 strength. There are many workbooks, and also instruction manuals for trainers, but I don't know how much they add -- by far most of the value is in going through the workbooks and solving the exercises. In my opinion, that series of workbooks form a comprehensive course.

Note that doing it that way, you hardly get taught anything by means of text -- it's all solving positions. Which is what chess *is*, in my opinion.

There are other such courses (like Yusupov's series of 10 books) that start off at a higher level, so one can do first one and then another.

# Answer
> 2 votes
My suggestion would be to get a book on basic chess strategy. \[Since I don't know of any for beginners in the English language, I'll let someone else edit this answer with a specific recommendation\]. This will help you understand the "abstract" ideas of the game like king safety, piece development, control of the center/open files/weak squares and so on...

As for the actual execution of concrete ideas, that's what tactics are for! It doesn't make much sense to add a collection of puzzles to a strategy guide, so you may want to get some other book or app for that.

# Answer
> 1 votes
welcome to chess and chess stackexchange!

Q1) I would recommend watching videos about some openings, and deciding which you want to play. You better have some moves in your head before a game!

Q2) There is not "everything you need to know" in chess as our understanding of it keeps growing, but a good way to learn what you might face is actually facing them. So play games, solve puzzles, and only buy a course if you think you really need it.

# Answer
> 1 votes
One thing that no one ever tells you, ever, is that you need to first try to realize that chess is a numeric game, i.e. a game of accumulating small, measurable advantages. Computers have helped us realize that a big deal, but rarely do you see anyone speaking to that in the context of comprehending the game fundamentals. Place the knight in the corner and see how many squares it can reach, then place it in the center and compare. Hopefully, that gives you a clue ... Don't study openings, please, that will delay your development for a long time. I am a 2200 player and I don't know openings - maybe first two or three moves and the names of opening systems associated with that, but that's about it. I play through the center, try to maximize my pieces strength, gain space. King safety can be also quantified, because king "unsafety" increases your opponent's pieces mobility when they gain a tempo by checking the king. Also, initiative is worth probably a pawn. Nothing but quantitative considerations, as you can see ... This way I aim to accumulate positional advantages or, in numeric terms, increase the value of my position, which, at some point, will manifest in tactical opportunities.

Good luck on your journey!

P.S. Sorry, I made it sound almost like you need to calculate the value of each move in a computer fashion - you don't have to. I sort of "eyeball" relative strengths of moves along the considerations above to choose the one that will improve my position the most.

# Answer
> 1 votes
Learn Chess with Dr.Wolf appears to check some of your boxes

* Interactive.
* Suitable for new players overwhelmed by the sheer amount of "focused" material out there.
* Covers all aspects of your game play with the "virtual" coach commenting on your move quality each move.

The stronger recommendation is to dig deep into really good annotated chess books which showcase a strong player punishing (while explaining why) the weaker player's moves.

Classics include:

* Chess Master vs. Chess Amateur (Euwe)
* Best Lessons of a Chess Coach (Weeramantry)
* Grandmaster meets Chess Amateur (Davis and Norwood).

If books aren't your thing, look no further than YouTube speedrun series by some of the more instructive (and less braggy) players (GM Naroditsky, GM Hambleton etc.) where they offer excellent guidance through all stages of the game while they take on entire rating classes of players starting from the lowly beginner.

---
Tags: learning, theory, beginner, study, online
---


title: Winning position after move one?

text:
# Question
Title: Winning position after move one?
**Question:** There are 400 possible two-ply openings; that is, positions that can arise after each player has made one move. Which of these positions, if any, are winning (either for white or for black) with perfect play?

**Context:** It's very likely that chess is a draw with perfect play, which would mean that there is no one-ply opening that gives white a winning position. This question asks about the *worst* first move for white; if there is any first move so bad that black is winning with correct play, then that move (combined with black's best response) would of course be an answer to this question.

On the other hand, there definitely are some three-ply openings where black is winning; for example, black has mate in one after 1. f3 e5 2. g4.

**My attempts:** I ran Stockfish 15 on a handful of two-ply openings that seemed most likely to be winning for white, along with the two one-ply openings that seem worst for white. The most promising lines I found were as follows (along with the depth and number of meganodes in my searches, plus the best continuation and comments on transpositions):

* 1. d4 g5: +2.95 (depth 55/68, 55298 MN; 2. Bxg5)
* 1. h4 g5: +2.87 (depth 52/72, 4894 MN; 2. hxg5)
* 1. e4 g5: +2.14 (depth 38/44, 301 MN; 2. d4, transposes to sideline of 1. d4 g5)
* 1. Nc3 g5: +2.12 (depth 39/47, 314 MN; 2. d4, transposes to sideline of 1. d4 g5)
* 1. d3 g5: +2.07 (depth 36/39, 173 MN; 2. Bxg5)
* 1. e4 f5: +2.07 (depth 41/53, 267 MN; 2. exf5)
* 1. e4 b5: +1.94 (depth 37/49, 135 MN; 2. Bxb5)
* 1. Nf3 g5: +1.80 (depth 44/59, 1020 MN; 2. Nxg5, transposes with 1. Nh3 g5 2. Nxg5)
* 1. Nf3 e5: +1.76 (depth 37/46, 177 MN; 2. Nxe5)
* 1. e3 b5: +1.76 (depth 34/41, 59 MN; 2. Bxb5)
* 1. e4 f6: +1.69 (depth 39/47, 302 MN, 2. d4, transposes with 1. d4 f6 2. e4)
* 1. d4 e5: +1.67 (depth 38/52, 200 MN; 2. dxe5)
* 1. g4: -1.55 (depth 35/48, 165 MN; 1... d5)
* 1. d4 Nh6: +1.53 (depth 35/45, 119 MN; 2. e4, transposes with 1. e4 Nh6 2. d4)
* 1. Nf3 f6: +1.52 (depth 33/40, 31 MN; 2. e4, transposes to sideline of 1. e4 f6)
* 1. Nc3 f6: +1.51 (depth 30/38, 62 MN; 2. e4, transposes to sideline of 1. e4 f6)
* 1. a4 b5: +1.50 (depth 44/61, 268 MN; 2. axb5)
* 1. c4 g5: +1.50 (depth 32/43, 34 MN; 2. d4, transposes to sideline of 1. d4 g5)
* 1. e4 Na6: +1.38 (depth 45/62, 2541 MN; 2. Nc3, transposes with 1. Nc3 Na6 2. e4)
* 1. Nf3 Nh6: +1.33 (depth 36/47, 110 MN; 2. d4, transposes to sideline of 1. d4 Nh6)
* 1. Nc3 Nh6: +1.19 (depth=41/51, 440 MN; 2. e4, transposes to sideline of 1. e4 Nh6)
* 1. Nf3 Na6: +1.16 (depth=38/49, 208 MN; 2. e4, transposes to sideline of 1. e4 Na6)
* 1. Nc3 b5: +1.14 (depth 44/57, 367 MN; 2. Nxb5, transposes with 1. Na3 b5 2. Nxb5)
* 1. d4 Na6: +1.10 (depth=37/44, 133 MN; 2. e4, transposes to sideline of 1. e4 Na6)
* 1. f3: -0.74 (depth 36/47, 114 MN; 1... e5)

I realize that all of these positions are way too complicated to expect a definitive answer in either direction (forced win or forced draw)--see this closely related question. Instead, what I'm looking for is reasonable evidence one way or the other, for all of the most unequal two-ply openings. For example, if white wins 90 times out of 100 when a strong engine plays itself (or when multiple strong engines play each other) from a given position, then I would regard that as strong evidence that the position is a win for white with perfect play.

**PS** since I know someone will say it otherwise: this is a theoretical question, and I'm not interested in "loophole" answers like resigning or letting your clock run out.

# Answer
1.g4 d5: -1.5 (depth 38, Nc3 next)
> 2 votes

# Answer
You've actually already done most of the "hard work" by getting the opening evals. The rest is just looking at the statistics for how often the engine wins against itself. Here is the data for Stockfish.

Given an eval of +2.5, Stockfish wins against itself about 95% of the time, so 1. d4 g5 is very likely winning for White.
> 2 votes

---
Tags: opening, analysis, evaluation
---


# Question
Title: Lowest rated player(s) who earned a GM norm
Who had the lowest rating when they earned at least one GM norm?

# Answer
I don't think he holds the record but IM Yochanan Afek was rated 2329 (and already 50 years old !) when he secured his first GM-norm by winning the Paris City Championship in 2002.

Putting aside GM-norms from special tournaments (Zonals or Youth Championships), I suspect only underrated youngsters might have achieved a norm while being rated lower.
> 3 votes

---
Tags: history, fide, rating, grandmaster, norm
---


# Question
Title: What are some good books that explain the strategic ideas behind the Nimzo-Indian Defence, from Black's perspective?
I'm looking for a book, which does not have to be modern at all, that comprehensively explains the strategic ideas of the Nimzo-Indian Defence from Black's perspective.

# Answer
I play the Nimzo. There is no doubt that Anatoly Karpov is one of the best, if not the best, strategic players of all times.. This link is a good point to start. You will find many analyzed games of Anatoly Karpov in the Nimzo.

In the same website, you will find analyzed games of Petrosian, Capablanca, Kramink, Alekhine, Botvinnik, Smyslov, etc. Almost all the world chess champions played the Nimzo. In the same website, you can find analyzed games of Nimzowitch, who was not a world chess champion, but invented the opening.

Here is the link: https://www.chessgames.com/perl/chess.pl?pid=20719&playercomp=black&opening=E20-E59&title=Anatoly%20Karpov%20playing%20the%20Nimzo%20Indian%20as%20Black
> 1 votes

---
Tags: opening, books, recommendations, nimzo-indian
---


# Question
Title: Russian Chess Federation leaves Europe (ECU) and joins Asia (ACF). What practical difference does this make?
Russia, which like Turkey is part in Europe and part in Asia, has formally left the European Chess Union (ECU) and joined the Asian Chess Federation (ACF).

I understand that this means that when these two FIDE associate member organisations organise team and individual championships then Russian players (who currently have to be affiliated with some other federation like FIDE) are no longer elligible to play in ECU tournaments and instead can play in ACF tournaments.

What other practical differences does this make to the players and the Russian Chess Federation?

# Answer
> 1 votes
Since the start of the war with Ukraine, Russia has been sanctioned by many European organizations in several fields. Chess is one of the them. Most likely Russian players would not have been allowed to play European chess tournaments in 2023.

With the change of Russia in FIDE from Europe to Asia, most likely, Russian players will not have a problem playing the Asian chess championship.

---
Tags: fide
---


# Question
Title: Positions where pawn promotion to queen is worse than to other piece
I'm looking for games from famous grandmasters, in which pawn promotion to a rook, a bishop, or a knight is a better move than queen promotion. I tried to Google some, but I couldn't find anything.

# Answer
Knight promotion is reasonably common (though not nearly as much so as Queening); Rook and especially Bishop, much less so, because the only motivation is stalemate avoidance(\*). Tim Krabbé has a collection of underpromotion in serious play. You can judge for yourself how famous the players are in each case: https://timkr.home.xs4all.nl/chess2/minor.htm

(\*) In principle one could also underpromote in order to *get* stalemated. This does not seem to have happened yet in actual play, but the same Krabbé page shows several examples of composed studies where such an underpromotion is the only drawing move.

P.S. Further Googling brings up a page that cites a drawing N-promotion in "a game between Michael Adams and Tony Miles at Tilburg on 17 November 1993": https://www.chesshistory.com/winter/extra/underpromotion.html

These players probably qualify as sufficiently famous . . .
> 21 votes

# Answer
Here is a list of underpromotions in famous games: https://www.chess.com/article/view/9-amazing-underpromotions

Underpromotion to a knight is not that rare, especially in cases where the new knight gives a check or fork. But bishop / rook underpromotions are exotic, usually to avoid a statemate.
> 8 votes

# Answer
https://www.youtube.com/watch?v=RptrNJFFJJw

This is the "trap line" of Albin Counter-Gambit. at 3:10, you can see that promoting to a Knight is better than promoting to a Queen, simply because promoting to Queen is too slow (not to mention it would be lost anyway), and Knight promotion delivers a check which lets you keep the initiative. It's a line that requires a lot of analysis, so if you are rated lower than 1600, you may feel overwhelmed by all the possibilities in this variation.
> 1 votes

---
Tags: history, pawn-promotion, famous-games, master-games, famous-moves
---


# Question
Title: Is there a way to ask stockfish from the command line if a position is "quiet"?
Is there a way to ask stockfish from the command line if a position is "quiet"? I am running a script like stockfish\_fen.sh to return the analysis, but I would like to also know if stockfish considers this position to be of positional or tactical nature.

# Answer
I don't think there is anything like that, and it'll never be implemented.

If you insist, you may want to look at how Stockfish does quiescence search. A "tactical" position would mean a dozen of long series of recursive calls. A "quiet" position would mean otherwise. However, this is a very dirty trick which might not work very well, you'd also need to do some programming.

There're other ideas, such as looking at the average branch factor, number of captures in the principal variation, the distribution of the scores... None of which is absolutely satisfactory.
> 4 votes

# Answer
Stockfish supports an `eval` command which dumps the static positional evaluation (not in a format that is meant for computer parsing, but it's still doable). You can parse the output of that, and then do a `go depth 1`. If the results differ by more than say half a pawn, the position is not quiet.

An alternative may be to look at the `pv` line returned by `go depth 1`. If it is longer than 1 move, the line is not quiet.
> 3 votes

# Answer
No, there is not. This page describes commands: http://support.stockfishchess.org/kb/advanced-topics/uci-protocol

Also you can get information about Stockfish, with these commands, if you are on Linux:

```
stockfish --help
man stockfish

```
> 2 votes

---
Tags: positional-play, stockfish
---


# Question
Title: What is the effect of the processor type for chess infinite analysis using the current version of Stockfish?
To find the best move, the dream of any chess player, chess engines are used extensively. Nowadays, the most popular chess engine is Stockfish. Many chess players, including top chess grandmasters consider Stockfish "the best chess player of the world." We, humans, are not considered the best chess players anymore.

Today is March 9, 2023. If you go the download section of Stockfish: https://stockfishchess.org/download/ You can find that the current version is Stockfish 15.1.

It is my understanding that a better proccessor can find better results in small amount of time because it can perfom calculations faster. However, my doubt is for infinite analysis without a specific time limitation. Like for example, a faster car can arrive to a destination faster, but at the end both will arrive to the same destination, unless we are talking about a space trip.

In my experience as a chess player, after you arrive with Stockfish analysis to a depth of 60, there are only insignificant differences. I consider that after a depth of 60, we arrive to something similar to the mathematical concept of asymptote or maybe more appropiate would be the concept of limit. Of course, I would like to learn if my understanding is correct. That is the reason behind this question. I am limiting this question to Stockfish to reduce the complexity of this question. What can you tell me about it?

I am asking to assume that the first analysis is performed with a Windows machine equiped with the best processor available, using the version for faster processors, version AVX2. While the second analysis is performed in a Windows machine equiped with an older processor using the version for older processors, version POPCNT. I am using only the Windows operating system, again, only to reduce the complexity of the question.

My understanding is that while the slower processor will stay at depth=60, but the faster processor will go further (maybe depth=70) but for practical purposes there will not be difference because both would have arrive to the same destination, asymptote or mathematical limit.

To support this idea, we have evidence that correspondence chess games end in a draw most of the time. To challenge this idea, we find that the chess rating of correspondence chess players is not equal. All the correspondence chess games are collected in several databases. So, we have what in statisics in called a representative sample.

# Answer
> 3 votes
The way the question is stated seems to conflate two concepts:

1. Does the accuracy of the engine reach an *"asymptote"* after depth 60 beyond which there are only *"insignificant differences"*. There is existing research on diminishing returns with search depth but little data on current engines and such huge depths, if only because of the enormous resource requirements to generate sufficient data there. However at least empirically, in top level computer chess competition, where engines often search in excess of 40-45 ply deep, there are still clear strength differences between engines and last-ply move changes still happen, so the gain from extra depth is likely to be more than 0 Elo even for current software and search depths. I don't see any way to meaningfully answer this question further because it's not well-defined, for example it is not clear what an *"insignificant difference"* is.
2. Because of the reference to *"processor type"* and *"AVX2"* vs *"POPCOUNT"*, there seems to be an implied, but not explicitly asked, question whether the type of processor has any further consequence besides more time. The answer to that is **no**. If one looks at an example in the commit history of Stockfish, you will see that most changes include a reference to "bench", which is the expected amount of searched nodes on a set of test positions. The development process **requires** that all versions on all test machines return the same answer. Because Stockfish almost exclusively uses exact (integer) arithmetic, even for its neural network, this is a workable restriction.

This being said, at least for the second question one would have to strictly add "assuming there are no bugs in the engine". Last month such a bug was found where in very rare cases some of the versions could return a different answer. Because of the above restrictions, such a bug would have to be limited to a very small amount of positions (so it is not found by normal test coverage) and have a strength impact that's 95% likely to be less than -2 Elo (because the testing process enforces this constraint before accepting any change).

---
Tags: engines
---


# Question
Title: Are all main lines and variations of chess openings necessarily SOUND?
Are all main lines and variations of chess openings necessarily SOUND?.

I mean since we can't know all possible games, unique games, which are so large, about 10⁴⁰, how can I be sure that all "book", "theory" openings are SOUND?

I mean that, may be, some "book" openings may be UNSOUND?

Strong CHESS Engines may, to a limit, can examine all "book", "theory" chess openings.

Sound chess openings should lead to a decisive, not drawish, games. If a white opening, should lead to white win. If a black defence, should lead to black win.

Sound book, theory white opening should lead to white win, provided that no inaccuracy, mistake or blunder, from the white. And the same runs for the black defence. Note that possible games are very large, approximately 10⁴⁰ unique games.

I suggest that this is why Super Grandmasters, stopped at 2850 Elo, no even the world champion could beat any strong chess engine.

Of course we exclude inaccuracies, mistakes, and blunders.

# Answer
> Sound book, theory white opening should lead to white win, provided that no inaccuracy, mistake or blunder, from the white. And the same runs for the black defence

> Are all main lines and variations of chess openings necessarily SOUND?

Using your incorrect definition of "sound" the simple answer is "**No**". There are no "sound" openings according to your definition. There are no openings which give either white or black a forced win with best play by both sides.
> 1 votes

---
Tags: opening, theory
---