title: Multiple opening books in Arena?

text:
# Question
Title: Multiple opening books in Arena?
In Arena, you can select an "Arena main book" which will be the chess opening book that will be displayed in the `Book/TB` tab. However, is there any way to merge multiple opening books into that tab? It would be useful to combine a couple of good normal books with, perhaps, a special gambit book.

# Answer
PGN files are simple flat text files. Using a program such as Notepad++ you can simply merge the PGN files containing the openings you wish, into a single PGN file. It's pretty simple.

That said, if the two books you're merging contain the same openings you will have duplicates. Accordingly another strategy is to find the largest PGN book of openings you can, and simply add the missing openings you seek.

You can also convert PGN books to other formats such as the native \*.abk format favoured by Arena.

Using one book at a time seems to be a natural constraint of Arena. So you will have much more success working within that constraint and adopting the idea of merging multiple books into a single one and using it.
> 1 votes

---
Tags: opening, engines, arena
---


# Question
Title: Generate Simple Mate In 1 From Tablebases (for kids)
I was trying to find a kid's app for chess that has some incredibly simple problems. However, all the apps I found had rather tricky problems. So I thought I would download 3 piece table bases and use SCID (or grep, if necessary) to create a 3-piece Mate-In-One tablebase PGN. Then just use that in iChess or any other problem app that allows PGN imports.

Much to my chagrin, the tablebases aren't in PGN format as I expected (and I cant even read them in a text editor. Guess I really misunderstand how these tablebases work).

Any solutions out there?

# Answer
It's possible to generate mates in 1,2,3 etc with tablebase, but that's probably not what you want. You should understand:

* You will need good programming knowledge
* You will need a week generating 6-men tablebase mates
* You will generate too many mates than you can possibly study

If you are confident in programming, you can do this:

* Modify the Gaviota tablebase generator (ask the author for source code). Find where it calculates distance-to-mate, if it's one (or two or three), print the position out.
* Modify the Syzygy tablebase generator. Syzygy reports distance-to-zero, so you may need to use online probing (e.g. Nalimov) or an engine.
* Use the public API in https://syzygy-tables.info. Start from a randomised position. Use the API result to move your position to mate-in-one.

If you don't have any idea what I'm talking about, generating mate positions with tableabse is not for you. You should:

* Buy a book with mate-in-one positions. There is an Android app that can read a chess diagram and convert it to PGN.

**EDIT**: You shouldn't generate total random FENs. You should try to generate FENs that either side has an extra rook, queen etc.
> 2 votes

---
Tags: engines, database, problems, tablebases
---


# Question
Title: How does Lichess rating compare to USCF?
Just wondering some examples of peoples' USCF rating to Lichess (classic lichess, 10 min+)

I know it's hard to compare different pools of players. But I think that considering how we do polling with sample sizes, the numbers could be similar once you have the appropriate offset calculated. I need examples of comparisons of the ratings, to know "what's the average offset"?

I figure if I am in the top 90% Percentile in lichess, then I should be at least top 70% in USCF or some comparison like that. (just as an example)

# Answer
> 2 votes
There is unfortunately no 'good' way to convert from Glicko-2 to ELO. While a lot of people claim they have a formula, there really isn't any system that maintains the same invariants and distribution curve when converting.

That being said, there are some ways you could try and 'convert' your score. For example, you could find people on lichess who have similar ratings to yours, and see if they are USCF rated. Also, playing in a couple OTB tournaments would be more than enough to give you an accurate sense of what your ELO rating is around.

Hope this helps!

# Answer
> 2 votes
From my personal experience, the ratings at lichess and most other online chess websites are drastically overrated in score. I know someone who uses lichess regularly. Although I don't know his USCF rating, he has a score of about 1600 on lichess. Having played him in real life, he seems to be more around 1000-1200 player.

Also, my rating on chess.com is about 1700, but in the last several times I've played in real tournaments, I seemed to be on par with those at 1500. (My USCF rating is 800, but that's a different story).

---
Tags: rating, elo, uscf, glicko
---


# Question
Title: Dynamic (not-drawish) response for black against the c3 Sicilian
Basically what the title suggests. Many of the responses to the c3 sicilian (`1.e4 c5 2.c3`) that I find online result in very drawish positions usually with queens off the board and very little dynamic play. I want lots of action and craziness while still being sound.

This is currently my favored variation (but this is still quite drawish and doesn't feel very 'Sicilian-y'): `1.e4 c5 2.c3 d5 3.exd5 Qxd5 4.d4 Nf6 5.Nf3 Bg4 6.Be2 cxd4 7.cxd4 e6 8.Nc3 Qa5 9.O-O Nc6`.

Here are variations that I've tried:

1. `1.e4 c5 2.c3 d5 3.exd5 Qxd5 4.d4 cxd4 5.cxd4 Nc6 6.Nf3 Nf6` (this goes on to be kinda passive for black and mostly boring).
2. `1.e4 c5 2.c3 Nf6 3.e5 Nd5`, which almost is awesome except it becomes really drawish after `4.Bc4 Nb6 5.Bb3 Nc6 6.Nf3 g6 7.d4 cxd4 8.Bf4 Bg7 9.O-O O-O 10.Re1 d5 11.exd6 exd6 12.Bg5 Bf6 13.Bxf6 Qxf6 14.Nxd4 d5 15.Na3 Nxd4 16.Qxd4 Qxd4 17.cxd4 Bd7 18.Nc2 Bc6`.

> Any ideas?

```
[fen ""]

1.e4 c5 2.c3 d5 (2...Nf6 3.e5 Nd5 4.Bc4 Nb6 5.Bb3 Nc6 6.Nf3 g6 7.d4 cxd4 8.Bf4 Bg7 9.O-O O-O 10.Re1 d5 11.exd6 exd6 12.Bg5 Bf6 13.Bxf6 Qxf6 14.Nxd4 d5 15.Na3 Nxd4 16.Qxd4 Qxd4 17.cxd4 Bd7 18.Nc2 Bc6) 3.exd5 Qxd5 4.d4 Nf6 (4...cxd4 5.cxd4 Nc6 6.Nf3 Nf6) 5.Nf3 Bg4 6.Be2 cxd4 7.cxd4 e6 8.Nc3 Qa5 9.O-O Nc6

```

# Answer
The line with Nf6 is actually pretty interesting. I think you overlooked the main line which is 6...c4, not 6...g6. For the record, the delayed d4 is the less popular variation. It leads to unbalanced play:

```
[fen ""]
1. e4 c5 2. c3 Nf6 3. e5 Nd5 4. Bc4 Nb6 5. Bb3 Nc6 6. Nf3 c4 7. Bc2 Qc7 8. Qe2 g5 9. e6 dxe6 10. Nxg5 Qe5 11. d4 cxd3 12. Bxd3 Qxe2+ 13. Bxe2 h6 14. Ne4 e5

```

There are of course other sidelines in this variation, with a major alternative being 9. h3 for white, but I encourage you to look into it some more.
> 5 votes

# Answer
I play the **Accelerated Dragon**, which is kind of an universal response to `1.e4`, and has the advantages of always being able to keep the positions into familiar territory for you: similar pawn structure, best squares for the pieces and many ideas are recurrent in different variations.

Against the Alapin (`2.c3`) Sicilian I suggest:

```
[fen ""]
1.e4 c5 2.c3 (2.d4 cxd4 3.c3 g6 4.cxd4 d5!) g6 3.d4 cxd4 4.cxd4 d5! {This position may also arise from the Smith-Morra gambit as shown above, so you are cutting off studying time! And it's completely sound.} 5.e5 (5.exd5 {This is the most challenging approach, but because of the position being not exactly the most played, advancing feels more natural.}  Nf6 6. Nc3 Nxd5 {Some theorists suggest that this is hurrying too much to get the pawn back, but if you don't take it now you may end up struggling to get it back.} 7. Bc4 Nb6 8. Bb3 Bg7 {This is a sample line where black has driven the game into his territory and achieved an imbalanced position. A draw would be the most likely outcome though}) (5. Nc3 {This is a tricky sideline that's not much played, but worth knowing at least a few moves deep.} dxe4 6. Bc4 Bg7 7. Qb3 e6) {This is probably the move you'll face the most, so I'll expand more on it.} Nc6 6. Nc3 Bg7 7. Bb5 Nh6 {The knight goes to f5.} 8. Nge2 O-O 9. O-O Nf5 {Notice how the e pawn is not yet moved, you don't want to lock your bishop in.}

```

The main idea behind this move order is that white's interesting possibilities are highly restricted compared to others. If he goes for the most challenging approach, he would have to commit to an isolated `d` pawn, which is not usually the taste of `1.e4` players. If not, the'll have to play an improved version for black of the French Defense or try some "one-move threat" lines.

You'll most likely face opponents that advance you on `e5`. The main idea for black is trying to put loads of pressure on the weak `d4` pawn. Moves like `Qb6` are always to be looked at, specially since it could potentially be a double attack against also `b2`. This is why white's bishop is developed to `b5`, to avoid the double attack and to allow exchanging an attacker on said pawn.

As said in the comments of the game, you *don't* want to play `e6` just yet. On some positions where black achieves the `d5` advance, the `Bc8` simply doesn't play. Now, he has an alternative route and on some variations it even goes to `e6` itself. This is why this position is, for black, much better than the ordinary French Defense position that it may "transpose" to.

This said, the main ideas of attacking on the queenside still hold, and an interesting move to know is a well-timed `f6`. This little pawn break allows the `Bg7` bishop to come into play with devastating effect, as the `d4` pawn normally cannot stand the pressure. Of course, such a move has to be always played carefully, but if `e5` would be possible in the near future, to take under control the whole center, it is definitely a good idea to consider it.

**Conclusion:**

If you like Dragon-like structures (or time is a big issue for you) and dynamic play, I encourage you to try this. The positions are essentially imbalanced, there is no queen trade in the near future and many tactical motifs typical from the Dragon are still playing an important role.
> 4 votes

# Answer
What about 1.e4 c5 2.c3 g6 3.d4 cxd4 4.cxd4 Bg7 5.Nf3 d5! personaly I'll try to play the Hyper Accelered Dragon (witch is the only way to make the Dragon viable for black I think) transposition would be 1.e4 c5 2.Nf3 g6 3.c3 Bg7 4.d4 cxd4 5.cxd4 d5! The same position arise, why wouldn't it be good with the Alapin move order ? I think it's good for black, you may try it also, good luck.
> 3 votes

# Answer
Something unusual, a bit crazy and probably incorrect... but defnitely worth a try, cuz it often works! Especially in blitz games. The variation I'm going to paste here is obviously after white has played badly, but a lot of people lose their minds when they face such a 'novelty'. When white plays correctly he gets some adventage obviously.

```
[fen ""]
1. e4 c5 2. c3 d5 3. exd5 Qxd5 4. d4 e5 5. dxe5 Qxd1 6. Kxd1 Nc6 7. f4 Bg4 8. Nf3 O-O-O 9. Kc2 Bf5 10. Kb3 c4 11. Kc4 Be6 12. Kb5 Rd5 13. Kc4 Na5#

```

Of course white blundered horribly with `9. Kc2` which is losing. Anyway, this move looks natural when you have `c3` played and that's probably why people are losing as white here. Of course `6. f4` isn't neccessary, `6. Nf3` is also okay. I like this variation, it's not drawish\*, which is what you asked for. You sacrifice a pawn for a development and the initiative. It's fun to play, try yourself! Hope you like it and share your results with us.

\*drawish is for example `4. Nf3 - Nc6 5. d4 - e5 6. Ne5 Ne5 7. de5 Qe5`

# edit

I should have mentioned: if white doesn't fall for that 'trap', you shouldn't try to take back that `e5-pawn` that brutally, but simply play `f6` and recapture with your knight. It's like someone said "be quick or be dead".
> 0 votes

# Answer
4fter After e4 c5 d4 cxd c3 d5 exd5 Qxd5 cxd4 e5 White can Simply play Nc3 and has a Little advantage After Qxd4 Dxd4 Nb5 Na6
> -3 votes

---
Tags: opening, sicilian-defense
---


title: Fathom syzygy browsing tool

text:
# Question
Title: Fathom syzygy browsing tool
I'm trying to make syzygy browsing tool **fathom.exe** work. If you have experience with this, please let me know. I tried million of combinations of tokens to format the position command and the program always returns empty string.

When I run this command

```
FILE* pipe = _popen("c:\\fathom.exe --help", "r");

```

program returns this info string:

```
usage: c:\fathom.exe [--help] [--path=PATH] [--test] FEN

WHERE:
FEN
    The position (as a FEN string) to be probed.
--help
    Print this helpful message.
--path=PATH
    Set the tablebase PATH string.
--test
    Print the result only.  Useful for scripts.

DESCRIPTION:
This program is a stand-alone Syzygy tablebase probe tool.  The
program takes as input a FEN string representation of a chess
position and outputs a PGN representation of the probe result.

In addition to the standard fields, the output PGN represents the
following information:
- Result: "1-0" (white wins), "1/2-1/2" (draw), or "0-1" (black wins)
- The Win-Draw-Loss (WDL) value for the next move: "Win", "Draw",
  "Loss", "CursedWin" (win but 50-move draw) or "BlessedLoss" (loss
  but 50-move draw)
- The Distance-To-Zero (DTZ) value (in plys) for the next move
- WinningMoves: The list of all winning moves
- DrawingMoves: The list of all drawing moves
- LosingMoves: The list of all losing moves

The PGN contains a pseudo "principle variation" of Syzygy vs. Syzygy
for the input position.  Each PV move is rational with respect to
preserving the WDL value.  The PV does not represent the shortest
mate nor the most natural human moves.

```

Can you write me please an **exact string command** to analyse for example

4k3/4n3/8/8/4K3/8/1B2B3/8 w - - 0 1

My wdl folder is C:/Tablebases/Syzygy/wdl

My dtz folder is C:/Tablebases/Syzygy/dtz

# Answer
> 1 votes
I have experience working with Fathom in one of my iOS apps. Look at my recent post:

http://talkchess.com/forum/viewtopic.php?t=62378

My command was: `fathom --path=YOUR_PATH --test "FEN_STRING"`

* Substitute `YOUR_PATH` with your path. You must have both WDL and DTZ files in the same directory.
* Substitute `FEN_STRING` with your FEN string. You will need the quotation mark.

My console session posted in the link:

---
Tags: programming, tablebases
---


# Question
Title: Looking for website for organising private tournaments with swiss system?
Do you know any website for organising online chess tournaments with swiss pairing method ? I know lichess.org but they don't support it anymore :/

# Answer
> 2 votes
The related question How to organize a chess tournament appears to have several suggestions; I'm not personally familiar with any of them, but most of the links seem to still be active.

# Answer
> 0 votes
You can do it on playchess.com in the 'tournaments room'.

# Answer
> -1 votes
You can try chess.com, but you must be a premium user to create a tournament.

---
Tags: software, tournament, online-chess
---


# Question
Title: Where can I find a rarity table of chess player ratings?
Now it's fine either as percentage of all FIDE players registered or just as number itself (like either 1/100k players are rated above X, or 23 players rated above X, respectively). Let's say by their peak rating and not necessarily current one.

If unclear what I mean, let's take an example: Last time I checked there were 10 players who reached a rating of over 2800 ELO at some point in their career. I don't know how many FIDE players there are, but if, say, a million, then rarity here is 10/1,000,000. Or we could simply use the number 10.

Now I'm looking for something similar but in a table, like with +2700, +2600, and all the way down. Do you think such information is available? Thanks.

edit: I wanted specific numbers which the other thread had not provided. I am happy with the answer I've chosen now.

# Answer
According to the list downloaded here, there are currently 261782 players with a FIDE rating. I wrote a small program to analyze it, and here are the results:

```
-------------------------
Rating  Number of players
2800+   5
2750+   18
2700+   43
2650+   114
2600+   262
2550+   514
2500+   921
2450+   1641
2400+   3130
2350+   5223
2300+   8669
2250+   13791
2200+   21033
2150+   30045
2100+   41411
2050+   54631
2000+   69229
1950+   83243
1900+   97932
1850+   112783
1800+   127483
1750+   141826
1700+   155776
1650+   168856
1600+   180987
1550+   192154
1500+   202332

```

Keep in mind that there are a lot of countries where club level players (1500 - 2000) have a national rating but not a FIDE rating.

For reference, here is the Java program I wrote. Feel free to modify it for your own analysis.

```
public static void main(String[] args) throws Exception {
    BufferedReader reader = new BufferedReader(new FileReader("rating.txt"));
    String line;
    int[] frequencies = new int[3000];
    boolean first = true;
    while ((line = reader.readLine()) != null) {
        if (first) {
            first = false;
            continue;
        }

        frequencies[Integer.valueOf(line.substring(113, 117))]++;
    }

    int total = 0;
    for (int rating = 3000 - 1; rating >= 0; rating--) {
        total += frequencies[rating];
        if (rating % 50 == 0) {
            System.out.println(rating + "+\t" + total);
        }
    }
}

```
> 10 votes

---
Tags: elo, statistics
---


# Question
Title: Why does White play 13. f3 and not 13. f4 in the Modern Benoni, Classical Line?
In the classical line, the book *Starting Out: Modern Benoni* by Endre Vegh recommends 13. f3:

```
[FEN ""]
[StartPly "26"]

1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. Nf3 g6 7. e4 Bg7 8. Be2 O-O 9. O-O Re8 10. Nd2 Na6 11. Kh1 Nc7 12. a4 b6 13. f3 (13. f4)

```

This is what the author says of 13. f3:

> the centre is thereby strengthened and will not be easily undermined.

**But given that White would like to push with e5, why not support it with 13. f4 beforehand?**

# Answer
> 6 votes
I played this position many times with white and f3 is really good move here.

It is not only about what white wants, but also about what black wants. You have more space and so you can choose easier from more plans. You can play for Rb1 b4, you can play for g4, you can play for f4 and e5. Black has not that much space and can't choose from many plans.

Now look at the position. Who will be happy to see f4 and potentially e5? Probably you in the beginning, but then also Qd8, Re8, Nf6 and Nc7. That is quite a body count. They don't have much work now but will have plenty of job after you weaken the centre. What about your pieces? Both knights will lose part of its mobility as they will have to protect pawn on e4. Bishop on c1 will hate you. Maybe you will help Rf1, while Qd1 and Be2 will see also slight improvement of their chances, but simple adding pros and cons of f4 action compared to f3 should lead to clear NO!. You won't loose the e4 pawn just by playing f4 or anything like that, but by this overextending on part of board where you really are not stronger, you achieve nothing positive at all.

**The plan is good only when it helps you more than your opponent!**

The f3 alternative with killing opponent's bishop immediately on c4 (f3 Ba6 Nc4 Bxc4 Bxc4 is the main line and for good reason, as black can't afford you to play b3 and retake on c4 with pawn!) saves you material advantage of bishop vs. knight, doesn't commit you to anything and then you can calmly go either for Rb1 b4 or some other stuff depending on black answer.

---
Tags: pawn-structure, modern-benoni
---


# Question
Title: How many FIDE-rated games must be played to obtain a *non* provisional rating?
I have a provisional FIDE rating of 1980 based on my score of 1 (two draws) out of 4 at a FIDE-rated tournament earlier this year; see: http://ratings.fide.com/card.phtml?event=2059100 where provisional rating is Rp. I am playing in another FIDE-rated tournament next weekend and I seem to recall it may take as few as 9 games against FIDE-rated opponents to obtain an official (*non* provisional) rating, though I'm having a hard time authenticating this.

This is important to me as it's a 5-round tournament coming up and I want to know whether taking a bye may mean I have to play in yet another FIDE-rated tournament after this one to reach the plateau of 9, if that is indeed the correct figure.

# Answer
> 4 votes
I want to add two details. First, FIDE does not have provisional ratings. The "Rp" you see on that page is your *performance* rating for that tournament. It is based on the rating of your opponents and your score in the tournament.

Second, only games against FIDE rated players count. You've probably figure that out as only 3 of your games were rated while you were thinking of playing 4 or 5.

# Answer
> 1 votes
5 games against rated opponents played in a rated tournament.

---
Tags: rating, fide
---


# Question
Title: How to determine objectively if a move is passive or aggressive?
I'm doing research about how different conditions or situations affect the decision making process in chess. For example if the opponent's ELO ranking affects the average time used for every move. In the example, both variables are numerical and easy to obtain. However I struggle when it comes to define if a move is more passive or aggressive (specially after the opening theory).

I noticed that, independently of playing style, there are some external factors that make us play more actively (aggressively, taking more risk) or passively (defensively, taking less risk). I read some articles that say it depends on the current position and the analyzer "strength" to determine with certainty, but that is too subjective for my purposes. There must be some some objective cues to help me.

I was thinking about the mobility (as in how many moves the player or the specific piece have after the last move) or/and if it is making or stopping a threat. Are there other cues or methods I could use to define if a move is passive or aggressive?

Is there software where I can analyze a complete game and give me this kind of output? Perhaps not if the movement was aggressive, but maybe if it is making a threat or reaching more mobility than before?

I also know that some software like Chessmaster, uses AI "personalities" and some make passive or aggressive moves as their traits. Can someone explain how the software chooses a move that may not be optimal but a passive one?

# Answer
Let me answer your questions precisely and technically:

* `Q: I also know that some softwares like chessmaster...?`

Nobody knows for sure because Chessmaster is closed source. Fortunately, it's **not hard** to replicate Chessmaster personalities. There're several ways to do it:

+ Define different piece-square-table (PST) for each personality
    + Define different tuning parameters for each personality
    + Scale the attacking parameters and/or defending parameters with a constant
    + Give an appropriate Contempt value

It takes some work to create a new personality, but it should be just minor changes to a working chess engine.

The Stockfish engine had an UCI option for optimizating attacking and defending parameters. This was done by scaling the evaluation score accordingly. For example, if you scaled your own king safety score by a positive constant greater than 1, the engine would be more defensive.

* `Q: How to determine if a move is aggregative or defensive?`

Tony, Brian and others gave good suggestions, but their suggestions are for human players and too abstract for a computer. If you want a computer to tell you whether a move is aggressive or defensive, you may need:

* Null move
* Monte-Carlo tree search

Null-move is simple and it's been implemented in various chess softwares. The idea is simple - if the move doesn't threaten anything, it should not be an aggressive move.

Monte-Carlo tree search goes even further. You can use it to determine the distribution of your payoff. If a move is aggressive, the margin error should be smaller. If a move is defensive, the margin error should be bigger.
> 4 votes

# Answer
I think that at the GM level, all moves are aggressive, after a fashion. All are designed to harm the opponent, even if a previous error has cost us the advantage.

Tal's moves may seem aggressive but frequently granted him remarkable defensive resources. Similarly, Petrosian's 'passive' style was anything but. They were elemental forces with wholly different styles.

I don't know how a chess program would rate one more as aggressive and another as passive, except for the obvious - checking may be deemed aggressive. Setting up a double attack may seem aggressive. Perhaps choosing the 2nd or 3rd best 'good' move would be considered passive. Or the lowest rated 'good' move that involved a pawn.

Perhaps a passive move is one that allows the other player the widest array of good responses. Yep, that rings true. That's my answer.
> 3 votes

# Answer
I would say a move is more aggressive if it involves one or more of the following:

1) Attacking an enemy piece, particularly a more powerful piece

2) Attacking a square near the opponent's king

3) Moving deep into enemy territory

4) Threatening to move deep into enemy territory

5) Moving forwards

I would say a move is more defensive if it involves one or more of the following:

1) Moving away from an attack by an enemy piece

2) Defending own piece

3) Defending a square near own king

4) Moving out of enemy territory

5) Moving backwards
> 1 votes

# Answer
You want to define it for some automat system? This will be very hard work to do if it should reflect the real meaning of passivity.

If you want some easy parameter not very concerned about precision of result, these come to my mind:

* Some function of target rank of piece.
* Some function of long term material imbalance in games.

For more complex logic you should probably ask some engine developers but this is closer to science than to everyday work and without good reason they will probabbly not be very cooperative.

Edit: even though I like Tony Ennis answer more, this one is still viable as it will do the work with waaaaaay less CPU resources.
> -1 votes

---
Tags: analysis, software, style
---


# Question
Title: How do you calculate pawn endgames, like if you have X number of pawns facing X numbers of opposite color?
I'll use a random example here with white to move, but I'm really asking about the general principles.

```
8/7p/6p1/pp3p2/3k1P2/PP6/1P1K1PPP/8 w - - 0 1

```

I'm a chess amateur and endgames drive me crazy. Every pawn can move in limited ways but when there are several, suddenly there are so many variations based on which one you move first and how the enemy reacts. Do chess experts really calculate all that? Or do they look and see, for instance, three pawns facing three pawns and right away know that's draw if king is located in a certain square?

In short, I'm sort of looking for some rules of thumbs that can help me analyze (like that pawn square rule about catching a pawn before it gets promoted) just to make pawn endgames manageable.

# Answer
> 3 votes
> Do chess experts really calculate all that?

No, they really don't.

In a position like the one you gave an expert would look at two things -

1) The opposition

2) Reserve moves

and only then start calculating.

The opposition is what you get when the kings are opposite each other with one square gap between them exactly as shown in your diagram. The player who "has the opposition" (a good thing) is the player who doesn't have to move.

The reason it's a good thing is because currently neither king can move forward because then the kings would be next to each other. Generally speaking the player who has to move their king first would have to move either sideways or backwards letting the other king advance when maybe they can attack the other sides pawns.

Here it's not so straightforward because white pawns stop the black king from going to c3, c4, e3 and e5 and black pawns stop the white king from going to c4 and e4. White might want to play f3 to cover e4 instead of e3 and black might want to play b4 to cover c3 instead of c4.

Reserve moves are all the moves each player can play before he has to move his king and lose the opposition. The more the better and one reason to be careful how you push your pawns in an endgame. Here white has 4 obvious reserve moves - f3, g3, h3 and h4. Black has only 2 - h6 and h5. If white plays his moves in the right order, f3, g3, h3 first (in any order) then he will get extra moves g4 and g5 if he wants them because black cannot take the g4 pawn without giving white a passed pawn. So right from the get go black is in bad shape. He is going to have to give way and let white advance.

So, black's only hope is that he can construct a fortress with his pawns so that even though he will have to let the white king come to d3 he can stop it getting to the fourth rank using his king and pawns.

Now it's time to do some calculation.

It looks at first glance that maybe black is just going to be able to go back to d5 with his king (once his reserve moves are used up) and then shuffle his king between d5 and c5 because that will stop the white king going to c4 or d4 and the f5 pawn stops king to e4.

The problem is that then white is going to play b4 when his king is on c3 and black's king is on d5. This will give white a passed pawn and the win after either black takes the pawn and white recaptures with the king or black pushes the pawn to a4 and black plays b3.

So, maybe black needs to play b4 himself first? Maybe on his first move? Now it doesn't matter what white does. If he takes on b4 then black recaptures with his a pawn and his pawn is on b4. If white pushes a4 then black's pawn is protected on b4 and if white leaves it then so does black and the white king is never going to get to c4 to double attack it because the black king can always shuffle between c5 and d5.

But!!! It is white to go first. If he wants to win he has to play b4 himself on the first move. Otherwise it's going to be too late. So, what happens next? Black must capture with the a pawn and white moves Kc2 forcing black to take the a3 pawn as well. White recaptures with his a pawn and he has broadened the base and has the distant pawn (which means that after they take each other's pawns white is going to get back to the kingside just before white).

An expert white would probably stop calculating here confident that he would win.

Let's look at how it might go.

```
8/7p/6p1/pp3p2/3k1P2/PP6/1P1K1PPP/8 w - - 0 1

1. b4 axb4 2. Kc2 bxa3 3. bxa3 Kc4 4. h3 h6 5. g3 h5 6. f3 Kc5 7. Kc3 Kc6 8. Kd4 Kb6 9. g4 Ka5 10. Kc5 Ka4 11. Kb6 Kxa3 12. Kxb5 Kb3 13. gxf5 gxf5 14. Kc5 Kc3 15. Kd5 Kd3 16. Ke5 Ke3 17. Kxf5 Kxf3 18. Kg5 Kg3 19. h4

```

and the f pawn queens.

# Answer
> 1 votes
In most cases you don't mate with pawns only, so the plan in all pawn endgames is clearly to **create a passed pawn and promote it**. This already determines what you should look for in these positions, namely:

* passed pawns, and whether you can create one
* king activity
* weaknesses / easily attacked and capturable pawns

There are a few (somewhat related) concepts which become important in such endgames, such as:

* **Corresponding squares**: basically if your opponent moves the king to a certain square your king has to be moved to a specific square
* **Mined squares**: squares you should not go to with the king
* **Zugzwang**: since any player is forced to make a move, this can be used in certain positions when there is no good move available; forcing your opponent into a position to make a bad move
* **Triangulation**: a method to force a zugzwang position
* **Opposition**: one specific type of zugzwang
* **basic king and single pawn versus king endgames**: how to win or defend these; topics like: as attacker put your king in front of our pawn, occupying *key squares*, how to defend (aiming for opposition),...

Regarding your example diagram, I would evaluate the position as follows:

* black's king is more active
* slight imbalance of pawns (3 vs 2 and 3 vs 4, but because there are doubled pawns it will be difficult to create a passed pawn)
* the f4 pawn could be weak and if white protects it with g3, he has weakens the white squares on the kingside, particularly f3 giving black an attack route

It is obviously impossible to win the game on the kingside as neither side will be able to create a passed pawn there (even if white gives away the f4 pawn). So let's look at the queenside and how the pawn structure could change there. Basically there are four options:

1. black pawns on a5, b4, white on a4, b3, b2; This is a closed pawn structure, basically white wants to move the king via d3-c4-b5 to attack the pawns, while black wants to move his king via d3-c2 to attack the white pawns. Neither of this can be forced as black can just shuffle the king between c5 and d5 (covering c4) and white between d2 and e2 (covering d3). Neither player can make progress. Draw.
2. black pawn on b4, white pawns on b3, b2. This is similar to the first position ("1"), where the kings can be prevented from entering.
3. black pawns on a4, b5, white pawns on a3, b4, b2; This is the most interesting position. White wants to put the king on c2 and play b3 in order to create a passed pawn. Black wants to walk the king via c4 to b3. As a result when the black king moves to c4 white wants to move the king to c2 to prevent that walk; and likewise if the white king moves to c2, black wants to move the king to c4 to prevent b3. If there are no pawn moves available on the kingside (or none that lose there), this can result in a position of mutual zugzwang for whoever goes first to c4 (black)/c2 (white). **3a**: white goes to c2 first, then the line could be 1. Kc2 Kc4, 2. Kc1 Kb3 3. Kb1 Kc4 4. Kc2 and white will play b3 and probably get a passed pawn and win; **3b** black king goes to c4 first, then white king goes to c2 and creates a zugzwang position where black has to allow b3 afterwards
4. black pawn on a4, white pawns on a3 and b2. This is similar to the previous position ("3") with corresponding squares.

Taking this into account, it seems that black does not want to create position "3", i.e. black does not want to play a4 in the original position. If white is trying to achieve position "3" by playing b4 in the original position, black can capture on b4 after which white ends up with a weak pawn on b4 which will be captured.

As far as I can see, neither side can make any progress on the queenside.

This leaves as the only option for a win some combined play on king and queenside. A plan could be to place a pawn as far ahead as possible, (e.g. a black pawn on h3), then try to capture the blocking pawn (white pawn on h2 in this example) with the king. If you do this you give up the queenside, so need to calculate exactly who wins the race. However in this particular position I don't see how such plan could be forced and I believe it is just a draw.

---
Tags: pawns, pawn-promotion, pawn-endgame
---


# Question
Title: Would games played between two perfect players always end up on a draw?
Imagine a scenario where you have two perfect players (i.e. they can consider all the possibilities in a very short amount of time and they choose **always** the right movement).

If they decided to play against each other, would all of their games end up on a draw?

# Answer
The answer is currently unknown. If you don't consider the opening (generally the first 8-15 moves or so), strong AI like Stockfish will generally show a clear optimal move in any position, and the majority of openings tend to yield a draw in these computer matches. However, as there are an incredibly large variety of openings, and this number scales exponentially with the number of moves, it is infeasible, at least in the present, for us to find a definitive answer to this question.
> 3 votes

---
Tags: theory
---


title: Sicilian defense answer to Bc4 and Qf3

text:
# Question
Title: Sicilian defense answer to Bc4 and Qf3
I am a very beginning player and something I see a lot in response to the Sicilian defense is Bc4, with white intending to play Qf3 next turn. I found that e6 is a good answer but I feel where I take it after that is pretty poor and I want to know a better answer. The following is how the game typically goes

```
[fen ""]
1. e4 c5 2. Bc4 e6 3. Qf3 a6 4. d3 b5 5. Bb3 d5 6. a3 c4 7. dxc4 dxc4 *

```

# Answer
> 3 votes
In your posted game you have done a decent job of harrassing and eventually marginalizing the White King bishop. Yet, do you realize that each of your first seven moves is a pawn move? Besides neglecting piece develpment, you leave your center rather unprotected, which partly defeats the purpose of using the Sicilian, and you expose yourself to the inconvenient discovered attack of e5. For the moment, the Queen/Bishop attack is sufficiently neutralized by your 2...e6 and that is the time to begin development of your pieces.

# Answer
> 1 votes
At 3...., you should play nf6 threatening 4.... d5. You need the Nf6 to protect the d5 pawn against exd5, e6xd5, Bxd5, etc.

If White plays nc3 to attack d5 again, you play Nc6 to threaten Na5, attacking the bishop.

# Answer
> -3 votes
Would highly recommend 3...Nf6. You have strong spots on both d4 and e5 to anchor your knight, the former targeting the Queen and weak c-pawn, and the latter targeting both the Queen and Bishop. 3...Nf6 also opens up Nc6, without having to worry about the pawn push to e5. Feel free to follow up with further questions

---
Tags: opening, sicilian-defense
---


title: How can I concentrate during training?

text:
# Question
Title: How can I concentrate during training?
During an actual over the board game, I can be very concentrated. It's almost as if I *feel* things like the danger an uncastled king is in, and it *matters* that I find the very best move.

But when I try to improve my chess at home alone with the board and the pieces, and do some exercise positions from a book, the feeling just isn't there. I look very superficially, my mind wanders, I have tunnel vision, and taking more time doesn't lead to more ideas.

What's a good way to improve my concentration level during training?

# Answer
> 3 votes
The first thing I would try is to simulate game conditions when doing your training exercises.

Set up a real board with a real clock and simulate playing conditions - quiet, no TV, no music, maybe some low ambient noise at most. Give yourself an arbitrary amount of time on the clock to complete the exercise - say, 3 minutes for easy exercises, 10 minutes for difficult ones, whatever - and have at it.

The fact that you train means you do not have a motivation problem. Your problem is in execution, so change the way you execute your training and experiment on that end.

Good Luck.

# Answer
> 3 votes
If you have a demanding job, studying in the evenings can be difficult. You can even have the feeling that your brain simply says, "No".

Personal Productivity Stack Exchange has many questions related to concentration, and many of the answers there should be relevant to chess training:

* Using the pomodoro technique: divide tasks or study session into sequences of intervals of roughly 25 minutes. Take a break after each 25-minute interval. This is one "pomodoro". Take a longer break after four pomodoros. (I'm just covering the basics of the technique here, obviously. One of the questions that mentions the pomodoro technique is My thoughts distract me, how do I keep my focus?.)
* If your mind still keeps wandering in spite of this technique, there are two things you can consider:
    + Meditation. (I haven't tried it myself, but it is often mentioned on Personal Productivity SE.)
    + Some vigorous exercise before a study session or during a longer break. (See also How to quickly restore concentration?, which is actually about restoring concentration after an interruption, but the answers are more generally applicable.)
* Make sure that you get enough sleep. In addition, you can also take a nap before a study session.
* Some people find it helpful to visualize goals to maintain motivation. Alexander Heyne (on YouTube) proposes a different approach to goals; see his videos on goal setting & outcome goals versus habit tracking (and process goals): Why goal setting DOESN'T WORK (and what does) and Stop Setting Goals - Stack Your Habits. He does not talk about chess study, but his ideas should also work for this.
* If concentration is still difficult in spite of all of the above, don't keep "banging your head against the wall". If you repeatedly force yourself to keep on studying in spite of being tired, you can create negative associations with studying chess.

# Answer
> 2 votes
> One can see more over the board than in the quiet of one's study.

Source: Attributed to Nikolai Krogius in *The wisest things ever said about chess*, by Andrew Soltis.

We can see that this is a common problem. We need to find **what motivates you** to study and **find a solution** to helping you achieve that.

I personally am **motivated** by:

* Material that is fun for me. My favourite openings, games by favourite players, endgame play etc.
* Studying a topic when I've been beaten in a game by having that weakness exploited. For example, Bobby Fischer swallowed a book on pawn endgames after blundering in one
* If I am able to combine both, then that is even better

I accomplish these by **making my own videos** on the areas that I would like to study. If my concentration drops whilst making a video, then I have to go back and remake the video.

# Answer
> 2 votes
It sounds very much like your problem is the same one students have a couple of months before their exams. Googling it seems that their study drug of choice is something called Modafinil with somewhere between 20% and 25% of students at some British universities supposedly using it to help them study in the weeks leading up to their exams.

There is some published research which suggests it might help.

> RESULTS: Improvements under modafinil were seen on spatial working memory, planning and decision making at the most difficult levels, as well as visual pattern recognition memory following delay. Subjective ratings of enjoyment of task performance were significantly greater under modafinil compared with placebo, but mood ratings overall were not affected. The effects of modafinil on creativity were inconsistent and did not reach statistical significance.
>
> CONCLUSIONS: Modafinil reliably enhanced task enjoyment and performance on several cognitive tests of planning and working memory, but did not improve paired associates learning. The findings confirm that modafinil can enhance aspects of highly demanding cognitive performance in non-sleep deprived individuals. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

But you should note that Modafinil is on the list of FIDE banned substances along with amphetamines (including ADHD drugs like Ritalin and Adderall), ephedrine (common in over the counter nasal decongestants - a few years ago a Scottish skier lost his Olympic bronze medal due to use of a nasal spray he bought in a pharmacy), caffeine and codeine.

Personally I'm a bit skeptical. If you woke up in the morning and took one of these and immediately opened your book of rook and pawn endgames then it might work. But if you logged on to an online chess site and started playing blitz you might be stuck there for 8 hours! Oh, wait, that second scenario happens all the time (or at least until it's time for lunch).

---
Tags: training
---


# Question
Title: What are some common tactics that arise when black has played h6?
What are some common tactics or ideas that arise when black has played h6 (or white has played h3) in front of his castled king?

An example I have in mind is, in this position, white can win a pawn with Bxh6, gxh6, Qxf6:

A less concrete but still important idea is, with a bishop on the a2-g8 diagonal (pinning black's pawn on f7), white often plans to sink his king's knight into g6 in a couple of moves:

# Answer
Two basic ideas:

1. Put a knight on f5; Black will have a hard time chasing it away with g6 without losing material.
2. Storm with your g-pawn to g5. Especially with the black knight still on f6, Black cannot avoid the opening of some lines.

Both plans would work in some circumstances with the pawn still on h7, but are a lot more effective with the pawn on h6.
> 7 votes

# Answer
In my experience, your second idea, sinking a knight in g6, is not very common. Some more ideas:

* piece sacrifice on h6 for two pawns and an open king
* piece sacrifice on g5 (not forced but tempting). If white has a pawn on h4 and rook on h1, the opening of the h file can often be very dangerous for black. This is also known as *fishing pole trap*
> 2 votes

# Answer
With usual piece placement for this struture it is good to be careful that with weak 8th rank king can get to serious troubles on h7. Qf5+ with knight on f6 lost after g6, occasionaly Ng5+ hxg5 Qh5#. Also any b1-h7 attack can be often very dangerous. Shelter on g7 is more often safer.

You can think out and write to comment some reasons for that as a training. Or you don't have to trust this statement, but I'm always very careful if my King must run after check to h7.
> 0 votes

# Answer
To understand this question, we must look at what the move ...h6 does to the protection of the black kingside position once it is played.

When black plays ... h6, he:

* Weakens g6 - no longer protected by a pawn on both f7 AND h7.
* Weakens h6 itself and makes it vulnerable to capture sacrifices.
* Weakens h5 as well because playing g6 now leaves the h6 pawn unprotected.
* To some extent it weakens ... e6 also, as a sacrifice on e6 and subsequent recapture by fxe6 results in g6 undefended. Do you smell a combination?

Whenever you move a pawn, you change the fundamental structure of the position most of the time, so be very careful. Pawn moves can have far-reaching effects.
> 0 votes

---
Tags: theory, tactics, castling
---


# Question
Title: Clarification in the book Logical Chess, Move by Move, by Chernev
I am working through the book mentioned and in game 8 (Przepiorka vs Prokes) at move 4 ...P-B4, which is black moves pawn to C5. The book states the following: "This move is almost indispensable in Queen Pawn openings. It is important not to play ...Kt-C6 first, as the bishop pawn must not be obstructed." Could someone shed some light on the importance of ensuring the queen's bishop pawn is unobstructed?

# Answer
> 2 votes
Often black plays b6/Bb7/c5 to support an attack against the White d-pawn, and at times even Na6 to support c5. Obstructing the c-pawn slows down or prevents these kinds of maneuvers. Nc6 is an awkward placement of the knight on the queenside with d5/e6 being played by black, as it has no real good second move from c6 to get out of the c-pawns way, thus losing time, if black wants to follow up with ...c6 or ...c5. The move ...c5 is a "breaking" move that black wants in many openings, including the Caro-Kann, the French, etc., and not just d-pawn openings. A knight on c6 is generally speaking a 'good' knight when ...e5 and/or ...c5 has been played, i.e., king's pawn openings, The Sicilian Defense, etc.

# Answer
> 1 votes
One thing would be it allows you to put more pressure on d4, having both the pawn and knight hitting it instead of the pawn being blocked behind the knight on c7. The king's pawn is usually supporting the queen's pawn on d5.

# Answer
> 1 votes
I've often thought that the author over-emphasized this point. But there are good reasons for ...c5 in Queen's pawn openings. This single move accomplishes three things. 1. Put pressure on d4, as @Jerry Snitselaar has said. 2. Make room for the Queen Bishop, assuming ...e5 is not workable. 3. Create a meaningful open file for a rook--again, assuming ...e5 cannot reasonably be played. (I say "meaningful" because it is relatively easy to open *some* file, such as with the a- or b-pawn, but usually a rook on the c-file hits more valuable targets, and besides, it is usually important to prevent White dominance on this file.)

---
Tags: colle-system
---


title: How to play better with Knight?

text:
# Question
Title: How to play better with Knight?
I'm solving tactics on http://chesstempo.com .

One of the things that I struggle with, is tactics involving moving the Knight several times. I find it very odd to calculate Knight movement beyond the first move and often miss very simple tactics as a result.

I have an ELO of ~1600 on chess.com and still sometimes miss simple tactics involving this piece.

Are there any ways to train yourself to be better at calculating Knight movement?

# Answer
> 2 votes
I've mulled this over a number of times. Here is what helps **me** play better with a knight. I offer it not as a general solution, but as a solution that has worked for me. I hope you find it useful:

1. Understand how the Knight moves COMPLETELY.
2. Understand ALL the Knight threatens COMPLETELY.
3. Understand that the value of the Knight relative to the Bishop may change.
4. Understand by colour, what the Knight threatens when he sits still or moves twice (Rule of Even).
5. Understand by colour, what the Knight threatens once he moves (Rule of Odd).

> **Point 1**. Most people know how the Knight moves described as a "L". I've found this to be inefficient since this is only visualizing **one** of his possible moves and it's possible to miss some of his possible moves thinking this way.

To truly see his potential a player needs to know **all** of his possible moves at once. Here's how I visualize it (and will try to explain clearly how I see it):

> Around the Knight is a **box** the corners of which match the colour he is sitting on. The Knight jumps **outside** of the box to the opposite colour squares touching the corners.

It is possible to look at a board and see this "*box*" while playing and see all of Knights potential moves at once, rather than just one. The ability to see this **box** rather than a **single** move is something of an epiphany.

> **Point 2**. Understanding **all the Knight threatens** at once, rather than a single threat allows the player to understand all the pieces he can **attack**.

Just as above (Point 1) where seeing all of a Knights moves show his true potential, seeing all he threatens shows all of his attacking potential. Many players identify what he threatens (in a somewhat sequential manner) one threat at a time. However, this is inefficient and may inevitably miss some. The ability to *visualize his box* allows a player to see **all he threatens** which allows a player to realize his full attacking potential.

> **Point 3**. Some theories of Chess don't assign the Knight a static value relative to the Bishop (meaning the same unchanging value). Consider this for a moment:

If the Bishop works best on an **open board** with far reaching open diagonals **BUT** the Knight can jump around pieces on a **crowded board** but whose reach is always limited, it stands to reason the Bishop's value increases over time as the board opens up and as the game goes on; whereas the Knight's value decreases overtime since the board opening up removes his advantage. Accordingly, consider assigning the Knight a value of 3.5 in the beginning of the game (Bishop at 3.0), and flip these values as the game goes on as it's appropriate.

> **Point 4**. An un-moved Knight threatens the **opposite** colour he's sitting on (or if he moves twice).

A Knight on **BLACK** is threatening **WHITE**. A Knight on **WHITE** is threatening **BLACK**. Remember this and consider it when considering position.

> **Point 5**. A moved Knight threatens the **same** colour he sat upon before moving.

A Knight moving off **BLACK** will threaten **BLACK** once he comes to rest. A Knight moving off **WHITE** will threaten **WHITE** once he comes to rest. Remember this and consider it when considering position.

These last 2 points really help in end-game situations where you're forced to chase an odious opponent around the board. If you want to threaten the same colour you sit upon, you must move. If you want to threaten the opposite colour, stay or move twice.

Good luck!

# Answer
> 1 votes
You suffer from "Knight Vision" problems.

:)

Do a series of visualization exercises whereby you randomly select a start square and an end square, and without looking at the board, write down all the shortest paths the knight can take to get there. Do 8 a day, every 2 or three days, always, and no more frequently than that (your brain won't absorb it all).

You WILL see improvement after several weeks.

---
Tags: tactics, knights
---


title: How to deal with unorthodox players?

text:
# Question
Title: How to deal with unorthodox players?
I am new to chess and know only a bit of opening theory and understand some general ideas like developing my pieces, threatening and controlling the center of the board, etc. but I struggle against players who follow no opening and just bring out the queen and run amok on the board.

How does one wanting to stick to principles deal with such unorthodox play? Am I just too new to understand that there are book responses to such moves or should I focus on repulsing pieces before I develop or should I just follow my plan for development?

Also, I would really appreciate any recommendations about resources for beginners.

# Answer
> 4 votes
Some beginners bring out their queen early, looking for "game."

Just make sure to defend everything the opposing queen attacks. In the process, you will develop your pieces and control the center, while the opponent has only the queen out. Then you'll win.

When you are a bit more advanced, you can offer some of your pieces to the opposing queen while you concentrate on building a winning attack. Here's an example of such a game

# Answer
> 10 votes
Just do what you would do against 'normal' players. Develop your pieces, occupy the center, castle your king, but at the same, watch out for tactics (which, against a lone queen, means: don't leave pawns or pieces undefended).

You can harass the queen during development to gain extra tempi (e.g. 1. e4 e5 2. Qg4 Nf6), that never hurts, but you can also just wait until your development is complete, and only *then* attack the queen. There are no 'book moves' for this.

# Answer
> 5 votes
For the first question I think Glorifindel just said the important, against whatever type of moves you always want to play good, reasonable chess.

For the second question, when I was beginning my chess career, I loved books of Czech author Ludek Pachman (Modern chess strategy, endgames, middlegame...) and even today I think I liked them not only because they were written in my native language. Imho they are way better than popular Nimzovich's My System. I have no doubt there is plenty of good material out there, this is just what I have good personal experience with. Good luck with studying chess!

# Answer
> 3 votes
The idea behind opening theory is that it is such because, besides showing what to do in opening situations, it also show what *not* to do; namely this means that a good way to practice opening theory is to take one line and purposely move a piece otherwise, so that you understand how to punish it (for example try the standard Spanish opening without the book and see how White/Black can capture this or that other pawn if played otherwise). This helps in the long run to understand in general how to punish moves that are out of book (if they were sound they would then be *in the book*, somewhere).

Coming to the actual question we see few different points:

> How does one wanting to stick to principles deal with such unorthodox play?

this depends very much on what you mean by "unorthodox play": if unorthodox means, say,

1.e4 b6 2. d4 Bb7 3.Nc3 e6

That is not really unorthodox, rather it follows a different principle of occupying the centre via indirect control; it is sound and it is indeed in the books, just not on Chapter 1. As a consequence either you just play following natural development or, if you wish, you can go deeper into those lines and learn their theory. If, otherwise, your opponent plays manifestly wrong moves, blundering pawn protections and the like, well, you just take that pawn on, say d5, left as a gift.

> I struggle against players who follow no opening and just bring out the queen and run amok on the board.

Well, if the Queen is running wild on the board then just developing the two Knights in their proper squares (f3-c3 vs f6-c6) will definitely make your opponent spend many tempi, resulting in their pieces **not** being developed. As a consequence you will then have major figures development and initiative; this, obviously, unless the Queen is there for a good reason (see for example all the lines containing the "poised pawn" on b2-b7 or the old-style King's gambits and Cambridge Springs variations).

> Am I just too new to understand that there are book responses to such moves or should I focus on repulsing pieces before I develop or should I just follow my plan for development?

I would say it is half-half: improvement in chess follows the path of both ideas/principles and book analysis. Continue doing what you are doing and the improvements and the results will come as the time goes by.

# Answer
> 1 votes
\[chess joke\]

First, you don't know "a bit of opening theory". You might have a few pet lines, but a better player would mop you up regardless of how much 'theory' you think you know, and will quickly turn that 'theory' into a poorly formulated hypothesis.

:)

\[/chess joke\]

Anyways:

Play dogmatically. You are young in your chess-age, and dogmatic play will punish those who want to bring their queens out. Play like Steinitz, Tarrasch, Rubinstein, in a classic sense.

What does this mean?

The Theory of Steinitz - http://exeterchessclub.org.uk/content/theory-steinitz

Rule #6 applies to you:

6.At the beginning of the game a player should not at once seek to attack. Instead, a player should seek to disturb the equilibrium in his favour by inducing the opponent to make an error - a preliminary before attacking.

...'equilibrium in your favour' being a lead in development for you caused by him bringing his queen out too early and playing cat-and-mouse with your knights and bishops.

And, maybe it's time for a basic strategy book, something shiny and new?

Chess Training for Post-Beginners

---
Tags: beginner
---


# Question
Title: What is the best defense for White against the Traxler Counter Attack?
I had posted the question Should Black avoid the Two Knights Defense because of the Fried Liver Attack? After seeing the *Traxler Counter Attack* from Black, it made me wonder if White should just avoid the *Fried Liver Attack* because of this. I have seen some variations on how the game is continued if Black plays the Traxler Counter Attack, but I am not sure what White's best response would be. In all variations, I have seen the continuation `5. Nxf7 Bxf2`

```
[FEN ""]
1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4. Ng5 Bc5 5. Nxf7 Bxf2+

```

If the game continues `6. Kxf2`:

```
[FEN ""]
1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4. Ng5 Bc5 5. Nxf7 Bxf2+ 6.Kxf2 Ne4 7.Kg1 Qh4

```

In the above game, I see Black with a growing attack on White, so I guess by best I mean, how can White avoid getting brutally attacked in the Traxler Counter Attack?

# Answer
> 1 votes
```
6. Kf1 is the best response.

```

It looks like this:

```
[FEN ""]
1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. Ng5 Bc5 5. Nxf7 Bxf2+ 6. Kf1 Qe7 7. Nxh8 Bb6 8. Bf7+ Kd8 9. Nc3 *

```

# Answer
> 1 votes
I wanted to have this as a surprise weapon with black, but was very disappointed even with immediate d4. Plus after Nxf7 black is on the edge of losing in the Kf1 line as was played in some correspondence games. And it is by far not clear what problems white has in Bxf7+. So for me this looks more like a rapid/blitz attempt. But for players who like mess and don't care that much about objective evaluation this looks very acceptable. No easy refutation, to get something white must go to the complications.

---
Tags: opening, two-knights, fried-liver-attack, traxler-counter-attack
---


# Question
Title: Best way to use UCI engine to play against itself
So far I used UCI only to make analysis of particular positions, sending FEN, showing multipv, analysing fixed depth/time, clearing hash for every next position.

Now I would like to make the same engine play against itself a blitz game and I guess this approach might waste a lot of CPU resources. Any information on this topic, ideally with example of UCI communication included, will be appreciated. Especially I want to ask:

**How should I setup hash and when should I clear it**? After each move, after reaching certain amount of nodes searched from last clearing to defend against hash colisions?

**Is there a better way than sending FEN after each move to UCI?**

**Should I setup multipv to 1 and always wait for "bestmove"?**

I'm not very concerned by slowdowns caused by fen parsing etc, but I would like not to make some huge mistake like clearing knowledge made on previous moves. Of course I want engine being able to reuse as much calculations as possible for both sides from last moves.

# Answer
I don't think it's a good idea to write a new framework. You should use Cutechess. CuteChess is free, stable, fast and reliable.

I'll answer your questions anyway:

* You should not clear the hash, it's the engine job to fill it and replace it
* You don't have to send FEN, you can also give a move list
* By default, multipv is 1 so you don't need to do anything
> 1 votes

---
Tags: programming, uci, blitz
---


# Question
Title: When should you charge pawns in front of a castled king?
In a situation where both players castle on the same side, is it ever a good idea to charge the pawns in front of the castled king? Are there any rules for when you can do this? I know that generally those pawns shouldn't move. But I am also increasingly finding it useful in my games to break up my opponent's king's defensive structure by pushing up pawns. If I don't see any obvious attack on my position, is it worth it?

Here is an example position from my previous game.

I played h3, stopping a further knight advance and looking at pushing g4 to close off the black's light square bishop. But my deeper idea was always to push those pawns right up to open up black's king. To be honest though, I'm still not sure whether this was a good idea at all.

# Answer
> 2 votes
As others have noted, you should not move the pawns in front of your king except in defense, with very few exceptions, such as:

1. The center is closed, and you can attack a "hook" pawn in your opponent's position by advancing *one* of your pawns before your opponent can break through in a meaningful way on the queenside. This strategy usually appears with the h-pawn attacking a kingside castled position with fianchetto, or with g5 (after a preparatory h5 to fix the opponent's h-pawn at h6), where he has not fianchettoed.
2. The center is closed, and you can open a file for a heavy piece attack by advancing and sacrificing a pawn, usually the h-pawn, faster than your opponent can attack on the queenside.
3. The center is closed, your opponent has no counterplay on the queenside, and you have occupied the e5 square with a pawn as White (e4 as Black), denying your opponent a knight position on f6 (f3). Typically, the g-pawn is the attacking pawn in this situation, though the h-pawn occasionally takes the stage.

For examples, take a look at the English Attack against the Najdorf/ Scheveningen Sicilian, the Alekhine-Chatard Attack against the French, the Bayonet Mariotti Attack against the Pirc, etc.

Note that *the center must always be closed*. In such types of positions, you should (as others have noted) play on the side containing your most advanced center pawn, i.e. in the direction they are *pointing*. So, in situations where both players have castled kingside, the center pawns will often be arranged d4-e5 for White, and d5-e6 for Black.

# Answer
> 2 votes
Generally you should play on side where you have advantage in total firepower (P=1, N=3,...). In case of pawn storm in front of your king, the advantage should be bigger than you usually need. You can start easily minority attack with one extra horsie on the queenside, but you should probably not weaken your king seriously when you are just one knight stronger there.

**Edit: To make the rule about firepower complete, I would say your king is somewhere around -8 for these calculations while your opponent's around -3. Takes time to get close to him while your king is already weak.**

In this position I would play for b4. Good rule is that bishop g2 is very bad kingside attacker!

# Answer
> 1 votes
> is it ever a good idea to charge the pawns in front of the castled king? Are there any rules for when you can do this?

What comes to mind first is King's Indian defence where Black attack on king's side (just as an example Gelfand - Nakamura, 2010).

The rule is as usual: side attack could be met by center (or opposite side) counter-attack, so you need to make sure that your center and Queen side survive long enough without much protection. The best measure to achieve this is to close the center first.

Attacking in front of castled kings will surely require from you to keep your rooks before your king too. And then the other side of the board will become absolutely unguarded. So when your opponent wins all the pawns on the other side he can just checkmate you by using his rooks or to create a passed pawn.

On your diagram advancing g- and h-pawns by White looks like nonsense. The center is not closed, and even more than that, Black have more pieces on the King's side than White. So Black can easily meet your g4 by f5. Also moving just f- and g-pawns will be hardly sufficient to open Black's king. You need your f-pawn too. But black pawn on e5 is too strong for this to ever happen.

# Answer
> 1 votes
This is common in many openings with an early f4/f5.

Some examples that I've played include:

The Closed Sicilian, where white has pawns on c2/c3, d3, e4, f4 and g3, sometimes called "The Big Clamp"

```
r2q1rk1/pp1b1pbp/2nppnp1/2p5/4PP2/2PP1NP1/PP2N1BP/R1BQ1RK1 b - - 0 10
[StartFlipped "0"]

```

White can play for a pawn storm starting with h3 and g4

The Dutch Defense, mainly the Stonewall

```
r1bq1rk1/pp1n2pp/2pbpn2/3p1p2/2PP4/2NQ1NP1/PP2PPBP/R1B2RK1 w - - 6 9
[StartFlipped "1"]

```

Black will typically play Ne5, and can play for an attack starting with g5

The King's Gambit Declined, by transposition from the Bishop's Opening.

```
r1bq1rk1/ppp2ppp/2np1n2/2b1p3/2B1PP2/2NP1N2/PPP3PP/R1BQK2R w KQ - 2 7

```

One of white's plans here is to exchange off Black's dark squared bishop before castling, then playing f5 and initiating a pawn storm with h3, and g4.

# Answer
> 0 votes
Personally, the set up I like for white is King's Gambit with a quick castle: pawns-\>g2 and h3, king-\>h1, and I think it offers more protection. the set up you have here doesn't allow for you to develop your pieces without losing your king's protection.

---
Tags: pawns, castling
---


title: List of Crazyhouse engines

text:
# Question
Title: List of Crazyhouse engines
I want to get a list of all (because they are certainly only a few existing) crazyhouse engines. I searched in lichess forum posts by googling "crazyhouse engine" and collected many names and links from 3 different posts.

Initial list, to complete:

Sunsetter

Stockfish (a well known engine, recently implemented for crazyhouse, seems to be the strongest for this variant in this thread, is the default used in lichess for crazyhouse, important news: has beaten jann lee consistently in informal match in this playlist)

Sjeng

Tjchess

Immortal

nebiyu

pulsar

sjaak

Crazyhouse by nathanlo99

# Answer
> 3 votes
From the computer list of the Crazyhouse Chess Variant Association:

And aside from that there is the multi-variant Stockfish that plays Crazyhouse.

And Crazyhouse by nathanlo99

---
Tags: engines, chess-variants, crazyhouse
---


title: How do you use 'en passant'?

text:
# Question
Title: How do you use 'en passant'?
I have been playing chess for years but I was just introduced *en passant* only recently. I keep on forgetting when to play this weird move. I keep on asking myself "is it on the 5th row or the 4th row" If there is an easy way to remember, please help.

# Answer
> 14 votes
Perhaps it helps if you remember the (presumed) reason for having this special move.

Originally pawns were only allowed to make single steps. This meant that pawns on adjacent files could not pass each other without running into the danger of being captured.

When the double step was introduced, pawns on adjacent files could suddenly pass each other (which would have changed the evaluation of many positions most notably in endgames). They could pass each other exactly in one case: white pawn on 5th row black pawn making double step (or equivalently black pawn on 4th row white pawn making double step).

So bottom line if you see a pawn passing your pawn without your pawn ever having a chance to capture it, it is time for en passant.

# Answer
> 5 votes
You can capture en passant when your opponent pushes his pawn twice (to the 4th rank (white) or the 5th rank (black)) and you have a pawn sitting next to it. Then you can capture the pawn as if it only moved one square - but only immediately after the pawn push of your opponent, you can't delay this.

If you have trouble remembering this rule, then perhaps having a position in your mind works better?

```
[FEN "rnbqkbnr/1ppppppp/8/p3P3/8/8/PPPP1PPP/RNBQKBNR b KQkq - 0 2"]
[White "White"]
[Black "Black"]

2... f5 3. exf6

```

---
Tags: en-passant
---


# Question
Title: How to deal with the Sicilian Wing Gambit?
The Sicilian Wing Gambit is never popular with good players, thus, it is only played as a surprise. But, how to deal with this unexpected surprise? It seems to me that all responses would just worsen Black's position. What to do if I face it?

```
[White "Wing"]
[Black "Gambit"]
[fen ""]

1.e4 c5 2.b4

```

# Answer
The easy way out is to just play 2…b6. This move certainly doesn't "just worsen" blacks position:

* Now both players can fiancetto the bishop, but a black bishop on b7 actually has a target, the e4-pawn.
* If white plays 3.bc bc the b-line is open. This makes the option of 0-0-0 quite unattractive, an option that is much more often utilised by white, especially in the sicilian.
* If white doesn't take on c5, he will sooner or later have to deal with the threat against b4. Actually, he will have to evaluate the threat against b4 every move!
> 7 votes

# Answer
I take the pawn and use it to cramp White's QN.

```
[fen ""]
1. e4 c5 2. b4 cxb4 3. a3 d5! 4. exd5 Qxd5 5. Nf3 e5

```

Black has a pawn, controls the center, and it's difficult for White to develop to effective squares.
> 4 votes

# Answer
The classic counterattack is 3.... d5. This attacks the White pawn and improves (not worsens) Black's position. If White plays e5, Black plays e6 and transposes into a quasi French defense, or just takes the a pawn, with a pawn up.

White's better bet is to exchange the e pawn for the d pawn, but then Black's queen ends up in a dominating position in the center because White can't move Nc3 to chase the queen.
> 2 votes

# Answer
What about 2...e6:

```
[fen ""]
1. e4 c5 2. b4 e6

```

It forces whites to reconsider its agressive behavior while giving good opportunities for blacks.
> 1 votes

# Answer
Step back for a moment and consider ideas: With 2. b4, white sacrifices a pawn for virtually nothing. His idea is to get a pawn on d4 without exchanging it for the black c-pawn (the basic underlying idea of 1...c5), but black will have ...d5 as a response and be fine. So, you accept the pawn with 2...cxb4 (there is no good reason not to - do not play in fear), and now white has to chose between 3. a3, a quasi-Volga gambit in reverse, or go for 3. d4. Both moves are met with 3...d5 by black. Black will end up with quicker development and a better pawn structure and should have an advantage going into the middlegame.
> 1 votes

---
Tags: opening, sicilian-defense, gambits
---


title: Advantages in chess game

text:
# Question
Title: Advantages in chess game
I want to know how I can get advantages in a chess game and what the different types of advantages are, e.g. space and positional advantages?

# Answer
The question isn't very clear...

An advantage in chess could be many different things:

* Space advantages by the pawn structure
* Pieces mobility/activity
* Pieces coordination
* Strong and weak square
* Pawn structure (isolated pawn, double or tripled pawn, majority or minority, backward pawn on open and/or close line)
* King safety
* Good or bad pieces
* Etc...

There are many forms of advantages, and I certainly forgot some...

And one way to get an advantage is to build on the very small advantages you have in your position at the end of the opening.

For example, in the main line of the King's Indian defense, white has space advantages but the king is under serious pressure.

I hope this helps a bit...
> 5 votes

# Answer
These all could be considered potential imbalances in the Silman universe. Because, you know, that is what chess really is all about.
> 1 votes

---
Tags: learning
---


# Question
Title: What happens when someone quits in the middle of a swiss tournament?
5 rounds of a Swiss Style Tournament passed and a person who was second in the table quit (withdrew). What should we do? What about points others earned wining him? What about people who lost against him? And what about his future games?

# Answer
> 2 votes
The General handling rules for Swiss Tournaments published on the FIDE website merely say:

> 5. Players who withdraw from the tournament will no longer be paired.

The rules don't say that he/she can't be included in the final ranking (unless the additional rules for the tournament say the contrary, I suppose).

The points that his/her opponents won should remain valid. (How to deal with ties between opponents in the final ranking - that is unclear to me.)

It is not clear why leaving a tournament should affect a player's future games, unless there are regulations that apply to a cycle of tournaments. For example, for the Regulations for the 2016-2017 FIDE World Chess Grand-Prix Series contain the following rules:

> 4.5 If a player withdraws from an event after completing 50% or more of the games, the rest of his games are lost by default. Unless a withdrawal is justified by serious injury or illness, he will forfeit his right to the prize for the tournament and be excluded from the rest of the World Chess Championship cycle.
>
> 18.3 Should a player withdraw from a tournament or the Grand Prix Series without proper justification to the WCOC, then an automatic penalty of €5,000 will be imposed by FIDE on the player and the player may be excluded from the next World Championship cycle.

For *official FIDE competitions* (not all tournaments fit this category), the following rules from the FIDE Tournament Rules (version from 2011) also apply:

> 5 (c) If a player withdraws, is excluded from a competition after the drawing of lots but before the beginning of the first round, or there are additional entries, the announced pairings shall remain unaltered. Additional pairings or changes may be made at the discretion of the CA in consultation with the players directly involved, but only if these minimise amendments to pairings that have already been announced.
>
> 9 (b) When a player withdraws or is expelled from a round-robin tournament, the effect shall be as follows:
> 1. If a player has completed less than 50 % of his games, his score shall remain in the tournament table (for rating and historical purposes), but the points scored by him or against him shall not be counted in the final standings. The unplayed games of the player are indicated by (-) in the tournament table, and those of his opponents by (+). If neither player is present this will be indicated by two (-).
> 2. If a player has completed at least 50 % of his games, his score shall remain in the tournament table and shall be counted in the final standings. The unplayed games of the player are shown as indicated as above.
> (c) If a player withdraws from a Swiss-system tournament, the points scored by him and by his opponents shall remain in the cross-table for ranking purposes. Only games that are actually played shall be rated.

---
Tags: tournament
---


# Question
Title: Was I right to capture the pawn in this position?
I played a blitz game against a 1900 player which I won. I'm interested in this position, with me as Black to move.

The computer recommended to take the bishop, but I didn't want to take it immediately, because I don't want to give their rook an open file. I thought if they want to take my rook, they better do it with the g pawn.

```
[FEN "r2q2k1/2p2ppp/2p2n2/p7/P2pr3/1BB2P2/1PP3PP/3Q1RK1 b - - 0 1"]

```

I played Rh4 to keep an eye on the pawn and if they were willing to kick it by playing g3, they'll end up with a weakened position. They replied with g3 as expected. And here I could take the bishop or the h pawn then the bishop, which is what I did.

Had I followed what the computer said, I would have been up 2.5 or 3 points in computer evaluation. What I did got me half a point to 0.8, which is strange, hence I'm asking this question. The computer didn't even bother moving the rook to the h-file.

In the position, what would be the best approach?

# Answer
**N.B. This answer is without the aid of a computer.** Here I compare 1...Rh4 to 1...dxc3

## 1...Rh4

The material difference in the given position is exchange + pawn vs. minor piece. This is a difference of 3 pawns. After 1...Rh4, white can win a pawn with 2. Bxa5. On paper this is now a difference of 2 pawns, but computers tend to overvalue pawn structures, so is probably penalizing black for the doubled, isolated c-pawns.

## 1...dxc3

I think that Black is better after this sequence, because:

* Black will soon be up 2 pawns
* Black has better placed pieces
* Black has the long term strategy of making the light square bishop a spectator by placing most of the pawns on dark squares

---

```
[FEN "r2q2k1/2p2ppp/2p2n2/p7/P2pr3/1BB2P2/1PPQ2PP/5RK1 b - - 0 1"]

1... dxc3 2. Qxd8+ Rxd8 3. fxe4 cxb2 4. e5 Nd5 5. Rb1 Nc3 6. Rxb2 Re8

```
> 8 votes

# Answer
Well, actually it's hard to spot this line without using computer assistance, so your choice in blitz game seems reasonable (except your opponent should have played Bxa5 which gives you a material advantage of pure exchange only).

```
[FEN "r2q2k1/2p2ppp/2p2n2/p7/P2pr3/1BB2P2/1PPQ2PP/5RK1 b - - 0 1"]

1... dxc3 2. Qxd8+ Rxd8 3. fxe4 cxb2 4. e5 Nd5 5. Rb1 Nc3 6. Rxb2 Rd1+! 7. Kf2 Rd4

```

Now Black threat with Nd1+, so they win an extra tempo to play Kf8 protecting against White's attack on 8th horizontal.

Thus Black keep their main idea to play Rb4 and c5-c4 winning material. The only way for White to save bishop is to play Ba2 and Bb1 which puts White's pieces into absolute zugzwang. So this ending is a total win for Black.
> 1 votes

# Answer
You reasoning for not taking on c3 is flawed, as the Rook will end up on the b-file after exchanges and cxb2, suffering inactivity to get back the black b-pawn. Bad\_Bishop's answer seems accurate to me.

After 6.Rxb2 then Rd1+ 7. Kf2 Rd4 (threat Nd1+) and -+. White is busted.
> 0 votes

---
Tags: strategy, middlegame
---


# Question
Title: Can there be two bishops on white tiles? If not, can my queen be capture and then promoted so I can win the game?
.

Can there be two bishops on White squares? If not, can my queen be captured and then be promoted so I can win the game?

I reallly. don't know what to do because I think you cannot that have two bishops on White squares when the bishop is the only captured piece.

# Answer
> 13 votes
Your only problem here is logistical. You can promote your pawn to any piece except the King, even if that means you have two bishops on the same colour squares, or two (or more) queens on the board; but according to the official rules, you must replace it physically with a piece of the correct shape and colour. What to do if no such piece is to hand?

In a tournament, the organisers will make sure to have spare pieces available for such contingencies; but in a home game, improvisation is the norm. For instance, if one of your Rooks has been captured, you can turn it upside down and call it a Queen. In this case, you can just say "that pawn is now a Queen", which ends the game immediately with checkmate.

# Answer
> 5 votes
11684's comment is correct. You can have 2 White bishops if you want. It is possible for you to have 9 Queens, if you want. You can't have:

1. A king
2. A pawn
3. Per Brian, a piece of your opponent's color

# Answer
> 1 votes
Good answers here already, but I don't feel like they actually answer the question(s).

> Can there be two bishops on white tiles?

Yes, there can. You can promote your pawn on g8 to a Bishop. Luckily you can use the dark-squared Bishop that has been captured, ready at hand at the top of your photo, for this.

Tony Ennis has summed up the only restrictions on promotion in his answer. If you still had both Bishops on the board, TonyK's answer explains how to deal with that logistically, so even in that case you could've had one dark-squared Bishop and two light-squared Bishops on the board.

> If not can I get my queen killed and change my pawn to a queen and win the game

This question has two parts/misconceptions, I believe.

First of all, you need to promote the pawn immediately as it reaches the eighth rank. As soon as it set foot on g8, it must be promoted before your turn ends, and it can't stay a pawn on g8. Therefore, you can't get your Queen captured/"killed" and *then* promote your pawn afterwards.

Secondly, just like you can have two light-squared Bishops on the board, you can also have two Queens on the board. If I understand you correctly, you're proposing that you sacrifice your Queen in order to be able to promote the pawn to a new Queen. This is not necessary; you can just promote to a second Queen right away. Again, like TonyK said, the only problem with that is logistics: If you don't have a second Queen piece at hand, stop the clock and look for one, or use an upturned Rook, or something else. Seeing as promoting to a Queen there immediately wins the game by mate, however, it's probably not necessary to do that.

---
Tags: rules, pawn-promotion
---


# Question
Title: Alternative approaches to chess engine programming
As far as I understand, roughly speaking, chess engines work by:

1. calculating all possible variations (game tree) up to some depth
2. evaluating the final position based on some criteria (material, piece activity...)
3. based on this evaluation decide for the best move

I fully understand that to have an efficient engine there are ways to prune certain lines, limiting the depth, etc; but this is not my question.

Question is: Are there any alternative attempts to program a (not necessarily strong, but not random either) chess engine, which does not follow this scheme?

# Answer
In the beginning years of computer chess, people have actually tried to teach computers chess in the same way as they do with humans, explaining strategic concepts like a healthy pawn structure or the initiative. These attempt were soon abandoned because the method you describe was much more successful.

Recently, there has been another attempt to let an engine teach itself chess via Deep Learning (probably encouraged by the success of Google's Go AI). According to the article I linked to, they were quite successful and managed to reach IM strength.
> 16 votes

# Answer
@Glorfindel is not wrong but deep learning approach to chess is really a fancy term for parameter tuning in chess programming.

Deep learning allows a chess engine to learn a evaluation function, something usually hand written by a programmer. During a game, it works like a normal chess engine.

Other possibilities:

* GPU chess programming
* Monte-Carlo tree search
> 3 votes

# Answer
Certainly! IF you truly just mean.... "in theory, are there other methods to code a chess engine?"... Then, yes!!

For instance.... one could store a copy of every possible position in chess (a huge number, I know), and have an evaluation for each one. Then, it's answer to any given question (i.e., "best move for white in X position"), will be known immediately just by looking up that board. Is the current state of computer hardware such that this would make any sense? Nah. But you didn't ask that.
> -4 votes

---
Tags: engines, programming, computer-chess
---


# Question
Title: Different number of day options in tournaments
I'm thinking of entering a chess tournament, and finding it very hard to decode some of the jargon in the tournament listings. The tournament I'm considering entering has 4-day, 3-day, and 2-day options, and I can't figure out how this works regarding the possibility of winning 1st place in your section. Can someone give a general run-down of what the consequences are of joining the 2-day option vs the 3- or 4-day? Can you still win the tournament? How could that work, given that you cannot possibly play some of the other people in your same section but who chose the 3- or 4-day option, since the time controls are listed as being different?

# Answer
> 1 votes
It's my understanding that all of the players, regardless of whether they started in the 2, 3 or 4-day options, merge on the final day of play. Playing fewer days means you will play faster time controls in the early rounds, so that everyone plays the same number of games, up to the final day's rounds, which are played at the slower time control. The winner is determined like in any other Swiss, by who has the most points at the end of the tournament.

---
Tags: tournament
---


# Question
Title: Does playing the King's Indian against 1.g3 put black at a foreseeable disadvantage?
I am currently in a turn based game where white opened with 1.g3. I clearly see that white probably (at least white *should*) will fiancetto his king's bishop on the next move, aiming to control the white squares.

I google'd 1.g3 and saw it's called Benko's Opening, and as I suspected will likely transpose into something else.

It's tough for black to know exactly how white will attack, and the king's indian does fit that scenario (not overly aggressive, gives options, and also doesn't give white a full center advantage).

So my question is, giving a game that started with Benko's Opening and black plays King's Indian, does this put black at a foreseeable disadvantage where white would easily be able to capitalize?

I can see the opening possibly taking this route

```
[FEN ""]
1.g3 Nf6 2.Bg2 g6 3.d4 Bg7

```

# Answer
No, there is nothing wrong with this approach for Black. A kingside fianchetto is a perfectly reasonable response to White's. You are likely to end up transposing to an actual King's Indian if White eventually plays c4, in which White's fianchetto is a fine setup but not a killer.
> 4 votes

# Answer
This *particular* position gives white the option of going 4.e4, transposing to a fianchetto Pirc. White doesn't go for c2-c4 in the Pirc, making it quite different from the King's Indian, and it may be that black isn't prepared for that. Also this move order is quite flexible for white because he still has choices for both his knights.

That's how white got black out of his preparation in a famous game by Benko vs Fischer in the Curacao Candidates, 1962:

```
[FEN ""]
[Event "Curacao Candidates"]
[Site "Willemstad CUW"]
[Date "1962.05.02"]
[EventDate "1962.05.02"]
[Round "1"]
[Result "1-0"]
[White "Pal Benko"]
[Black "Robert James Fischer"]
[ECO "A00"]
[WhiteElo "?"]
[BlackElo "?"]
[PlyCount "80"]

1. g3 Nf6 2. Bg2 g6 3. e4 d6 4. d4 Bg7 5. Ne2 O-O 6. O-O e5
7. Nbc3 c6 8. a4 Nbd7 9. a5 exd4 10. Nxd4 Nc5 11. h3 Re8
12. Re1 Nfd7 13. Be3 Qc7 14. f4 Rb8 15. Qd2 b5 16. axb6 axb6
17. b4 Ne6 18. b5 Nxd4 19. Bxd4 Bxd4+ 20. Qxd4 c5 21. Qd2 Bb7
22. Rad1 Re6 23. e5 Bxg2 24. Kxg2 Qb7+ 25. Kf2 Rd8 26. exd6
Nf6 27. Rxe6 fxe6 28. Qe3 Kf7 29. Qf3 Qb8 30. Ne4 Nxe4+
31. Qxe4 Rd7 32. Qc6 Qd8 33. Kf3 Kg7 34. g4 e5 35. fxe5 Rf7+
36. Kg2 Qh4 37. Rf1 Rxf1 38. Kxf1 Qxh3+ 39. Qg2 Qe3 40. Qe2
Qh3+ 1-0

```

So that's something to look out for, it's not automatically a problem but it's different. Black can prevent this by playing an early d7-d5, but then it's not a King's Indian anymore either.
> 4 votes

---
Tags: opening, kings-indian
---


title: Winning percentage in chess 960

text:
# Question
Title: Winning percentage in chess 960
How does the winning percentage (white win/draw/black win) in chess 960 (Fischer random) compare to that of regular chess? Are there more white wins, fewer draws,...?

# Answer
The CCRL 40/4 FRC engine competition that has run through almost 200,000 games running night and day come up with these stats:

Chess960 FRC based off 200,000 or so games: White wins: 80'914 (41.6%) Black wins: 70'840 (36.5%) Draws: 42'546 (21.9%) White score: 52.6% http://www.computerchess.org.uk/ccrl/404FRC/rating\_list\_all.html

Standard chess based off 1.4 million games: White wins: 547'582 (39.2%) Black wins: 447'252 (32.0%) Draws: 403'047 (28.8%) White score: 53.6%

As you can see, there are significantly fewer draws among the engines and slightly more black wins. These days, the top engines are playing the Chess960 opening fairly well so the stats aren't completely useless. As for top quality human games, there are less than 2000 on the records which is way too small a sample.

A rudimentary case study was carried out to find out if there were any really unfair start positions in Chess960, but none were found. Each of the 960 starts offers players something reasonable. Here is where it was done: http://chess960jungle.blogspot.com.au/search/label/SP%20analysis

I can't post more links as references because the site won't let me. The problem with Chess960 right now is that most of it is being played online at blitz time controls which is useless for statistics.
> 9 votes

---
Tags: chess-variants, statistics, chess960
---


# Question
Title: I have an unusual chess set and am seeking advice
As suggested, I have reworded my question. Hope this is more appropriate.

Many years ago (circa 1988/89) I had commissioned and made a chess set of key characters from the American Independence (American, French and British figures).

This is a one-off (the casts were broken after use) and is hand crafted/painted, made from solid pewter.

I have a data sheet for the set (albeit photocopy quality) detailing the pieces. This set has never been used so the condition is mint.

I was collecting sets for quite a few years and did intend to display this one but never got round to it.

What I am after is advice from the forum as to what to do? I have stopped playing and collecting a long while ago. It's not that I am not a fan of chess but lack a regular playing partner and work consumes so much of my time (particularly when travelling), I can never seem to get the time to even set them on display on the few boards I have.

Sensible comments appreciated.

Thanks

p.s. for information/interest I have uploaded pictures of the set I have described in this post

# Answer
> 1 votes
Amazon, ebay, and top local online shop in your country

---
Tags: chess-set
---


# Question
Title: How can I generate legal random chess setups?
Is there a free online website that attempts to generate "legal" random chess setups X amount of moves into the game?

# Answer
> 1 votes
I was unable to find an online tool to do this, but in terms of how, the following appears to be the logic that would be used:

* Both white and black pieces would be in the correct starting positions;
* White would start;
* Turns following white's start would be exchanged between white and black;
* Any piece able to move during a turn would be a member of the list of pieces to be randomly selected to move;
* Once a piece was selected, all squares for that piece that are legal moves would be added to the list of possible moves, and a move would be selected randomly from that list;
* Attacks would not take place unless the attack was randomly selected as a move. If an attack does take place, then the attacked pieced would be removed from the board.
* Iterations of randomly selected moves would stop once the number of moves into the game set before generating the board had been reached.

# Answer
> 8 votes
I stumbled upon Chess Hero. It looks very nice, but it is not online. Per the website:

1. You supply a set of PGN files
2. The program picks random positions from the PGN files and challenges you to guess the best move computed by a chess engine
3. On every attempt you are given a penalty (the difference in score between your move and the engine best)

The software can be found here.

# Answer
> 6 votes
Find an online database of games. Choose a random game and a random move in that game. Voila, an instant realistic and legal position.

# Answer
> 2 votes
I've actually programmed precisely that in PHP to test a hypothesis two days ago. If you're interested, I've uploaded the code to github for you: https://github.com/dennisvink/php-random-chess-move-generator

# Answer
> 0 votes
Besides the two ways already mentioned:

1. Pick a random position from a database.
2. Play a random amount of random moves.

We should also mention the most simple:

1. Generate a totally random position. Validate it. If not legal repeat.

You should be able to find lots of tools for analyzing if a position is legal. (E.g. exactly one king on each side etc.)

# Answer
> -2 votes
How about using live games from lichess? Here is an example call to the server. See the docs for pulling a list of users currently playing.

# Answer
> -2 votes
I think Lichess training do just that. It's software take a game position from it's database and challenge you to pick the best one based on Stockfish analysis.

---
Tags: learning, software
---


title: Check by Knight NxC3+ Move Implications

text:
# Question
Title: Check by Knight NxC3+ Move Implications
Here is the game I played which belongs to `ECO C34`. I would like to know Check NxC3+ implications. I couldn't cut the Knight. In which are the ECO games this NxC3+ can arise. Thanks for your comments and analysis in advance.

Here is the PGN.

```
[fen ""]
[Event "Live Chess"]
[Site "Chess.com"]
[Date "2017.01.12"]
[White "anandsadasivam"]
[Black "keviano7"]
[Result "0-1"]
[ECO "C34"]
[WhiteElo "643"]
[BlackElo "667"]
[TimeControl "600"]
[Termination "keviano7 won by checkmate"]
[CurrentPosition "rn3k2/ppB2bp1/8/3p1B2/1b1P2P1/7P/PPP5/R2Kq3 w - - 0 20"]

1.e4 {[%clk 0:09:59]} e5 {[%clk 0:09:50]} 2.f4 {[%clk 0:09:53]} exf4 {[%clk 0:09:13]} 3.Nf3 {[%clk 0:09:43]} Nf6 {[%clk 0:09:04]} 4.Nc3 {[%clk 0:09:35]} Bb4 {[%clk 0:08:51]} 5.d4 {[%clk 0:09:28]} O-O {[%clk 0:08:43]} 6.Bxf4 {[%clk 0:09:25]} Re8 {[%clk 0:08:28]} 7.Bc4 {[%clk 0:09:17]} Nxe4 {[%clk 0:08:20]} 8.Ng5 {[%clk 0:09:06]} Nxc3+ {[%clk 0:08:16]} 9.Kd2 {[%clk 0:08:00]} Nxd1+ {[%clk 0:08:11]} 10.Kxd1 {[%clk 0:07:59]} d5 {[%clk 0:07:22]} 11.Bd3 {[%clk 0:07:32]} f6 {[%clk 0:06:53]} 12.Bxh7+ {[%clk 0:07:27]} Kf8 {[%clk 0:06:36]} 13.Nf3 {[%clk 0:07:07]} Bg4 {[%clk 0:06:08]} 14.h3 {[%clk 0:06:27]} Bh5 {[%clk 0:05:37]} 15.g4 {[%clk 0:06:18]} Bf7 {[%clk 0:04:41]} 16.Nh4 {[%clk 0:06:09]} f5 {[%clk 0:04:31]} 17.Bxf5 {[%clk 0:05:59]} Qxh4 {[%clk 0:04:22]} 18.Bxc7 {[%clk 0:05:29]} Re1+ {[%clk 0:04:09]} 19.Rxe1 {[%clk 0:05:17]} Qxe1# {[%clk 0:04:05]}
0-1

```

For reference here is the FEN.

```
[FEN "rn3k2/ppB2bp1/8/3p1B2/1b1P2P1/7P/PPP5/R2Kq3 w - - 0 20"]

```

# Answer
I am not sure what you are asking. This is not a question of any eco or opening but rather of tactics which you were missing. After Nxc3+ (discovered check), you lose the queen and basically the game. There are two main themes in this game:

1. **pin**: of the knight on c3 by the bishop on b4; Therefore the pawn on e4 is not protected anymore as you cannot move the knight
2. **discovered check**: These are in 99% of cases deadly as the piece which moves out of the way (in your case the knight on e4) can capture a piece or attack a stronger piece (in your example both happens as black first captured on c3 and thereby attacked the queen on d1), while you have to deal with the check first and cannot recapture or secure your stronger piece.

If you practice tactics (which you should particularly as a beginner playing an opening like the king's gambit which is very tactical) you will be more aware of these themes and will be able to avoid them in the future.

You should have prevented this earlier. For instance 6. Bxf4 seems unnecessary as this pawn would be very difficult to protect for black and would fall sooner or later anyway.

Instead I'd suggest 6. Bd3 and castling as soon as possible in order to get out of the pin of the c3 knight and also out of any problems on the e-file as in your game.
> 8 votes

# Answer
After 4...Bb4 5. e5 makes Black look scattered. White mobilizes nicely after 5...Nh5 6.Nd5 Nc6 7.Bb5 Be7 8. 0-0 0-0 9. d4.

The problem with 5. d4 is it makes good on the Bb4 pin on the Nc3. 5... Nxe4 is possible immediately, instead of ...0-0. But even so, as in the game, after 5... 0-0, 6. Bxf4 is simply not paying attention to the e-pawn, and as suggested already, 6. Bd3, 6. Qd3, or even 6. e5 are better moves.

Tactically speaking, you should shy away from the King's gambit unless your tactics are tight and fast. Dropping a queen by move 9 tells me this is not so. Play to your strengths.
> 2 votes

---
Tags: analysis, kings-gambit, eco
---