title: Could Ding win this endgame vs Carlsen?

text:
# Question
Title: Could Ding win this endgame vs Carlsen?
Could Ding win this endgame vs. Carlsen (at this point in the diagram), in the game played yesterday at Lindores Abbey? Without using engines, it seems logical to me to play 41.Re3 or 41.Rd3 (instead of 41.Kc5 as played by Ding), with the idea of leaving the f2 Pawn to its destiny, but clearing a way for the King to the g6 Pawn, and eventually winning Black's other Pawns, while the White Rook is defending the g3 Pawn.

```
[fen "8/1k6/6p1/3K1p1p/1P5P/5RP1/4rP2/8 w - h6 0 1"]

```

# Answer
This is a book draw. At our level it is difficult but at GM level this is an easy version of KR+3 v KR+4 with the extra pawn on the the queenside. The fact that Black's king is already in position to block the passer makes it much easier than the classic version of this endgame. His very active rook is another plus. White is not going to lose but he can make at best token efforts to win.

> Without using engines, it seems logical to me to play 41.Re3 or 41.Rd3 (instead of 41.Kc5 as played by Ding)

These moves make no sense. Black is then going to play Rxf2 and follow up with f4. Soon the kingside pawns will be eliminated and the draw becomes much easier.

Jonathan Rowson devotes 42 pages to this endgame in his book "Amateur to IM". If you want to find out more about this endgame then his book is highly recommended.
> 2 votes

---
Tags: endgame, carlsen, rook-endgame, ding
---


# Question
Title: What’s the point of early ...a6 move in Queen’s Gambit Declined?
As title above, what is the point or the main idea of a very early ...a6 Pawn move in Queen’s Gambit Declined? I see that the move is fairly popular at GM and even top level.

# Answer
It is hard to tell exactly without an exact line, but normally it has the idea of following with ...dxc4 (putting the enemy bishop on the c4 square), ...b5 (now kicking it away) and ...Bb7.

This solves the annoying problem of placing the c8 bishop on a decent square
> 4 votes

---
Tags: opening, queens-gambit-declined
---


# Question
Title: How do I determine the bye player in a given round of a round-robin tournament?
The Berger tables for round-robin tournaments state:

> Where there is an odd number of players, the highest number counts as a bye.

As far as I understand this statement correctly, this means that, for example, in an 8-player round-robin, the 8th seeded player will always be the bye player and hence will not play any game.

What else could this mean?

# Answer
> 6 votes
It means that in the pairings given in the tables, if there are an odd number of players (so not an 8-person round-robin for instance), the player *playing against* the highest number receives a bye.

For instance, for 5 players (use the 5-6 player table):

* Round 1: #1 gets a bye
* Round 2: #4 gets a bye
* Round 3: #2 gets a bye
* Round 4: #5 gets a bye
* Round 5: #3 gets a bye

# Answer
> 1 votes
Its all documented here: https://www.fide.com/fide/handbook.html?id=184&view=article

Example: Where there is an odd number of players, the highest number counts as a bye.

```
9 or 10 players:
Rd 1: 1-10, 2-9, 3-8, 4-7, 5-6.
Rd 2: 10-6, 7-5, 8-4, 9-3, 1-2.
Rd 3: 2-10, 3-1, 4-9, 5-8, 6-7.
Rd 4: 10-7, 8-6, 9-5, 1-4, 2-3.
Rd 5: 3-10, 4-2, 5-1, 6-9, 7-8.
Rd 6: 10-8, 9-7, 1-6, 2-5, 3-4.
Rd 7: 4-10, 5-3, 6-2, 7-1, 8-9.
Rd 8: 10-9, 1-8, 2-7, 3-6, 4-5.
Rd 9: 5-10, 6-4, 7-3, 8-2, 9-1.

```

As result - who ever plays highest number - has bye, for example round 5 Nr3 gets bye as he plays against 10.

---
Tags: rules, round-robin
---


# Question
Title: Term for checking piece whose opponent daren't capture it
What if any, is the term for a piece whose owner gets a draw by keeping up a relentless series of checks with it -- a paradox being that even if this player puts it *en prise*, the opponent daren't capture it because that would deliver stalemate?

The piece is in many cases a rook, and I have come across the terms "rambling rook" and "roving rook", but they seem to mean something else.

I've also come across the term "desperado", and that seems to mean something similar, but it is not the same. A desperado is a piece which might do some damage, e.g. delaying-checks, but they merely delay mate: those checks run out, and the other side captures the desperado without stalemating, and goes on to win.

The tactic is an unusual form of perpetual check. In most perpetual checks, the checking piece switches back between two squares on neither of which is it *en prise*.

# Answer
> 14 votes
I'd use the term you already mentioned, "rambling rook", for this (at least when it's a rook). Tim Krabbé claims to have invented it:

> If the term 'Rambling Rook' sounds unfamiliar, this could be because I invented it. In Russian it is beshenaya ladya, in Dutch dolle toren, both meaning 'crazy rook.' There is no English term, and I thought a little alliteration would be in its place.

Here are a couple of usages, showing that the term is quite widespread:

Rambling Rooks, compiled by SwitchingQuylthulg on chessgames.com

> ### Rambling Rooks
>
> Witness rooks selflessly throw theirselves at the opponent's mercy again and again... until there is no choice but to take them and accept draw by stalemate.

Can you stop the rambling rook? by user Sleafar on our sister site Puzzling Stack Exchange:

> The rook can't be taken, because black couldn't move anymore which is a stalemate (= draw). If the king moves away the rook will continue to give checks.
>
> Can you stop the rambling rook and find a way for white to win the game anyway?

# Answer
> 4 votes
Well, that's only possible with a rook or a queen (at least, in most realistic situations) and indeed it's a typical theme in rook endgames.

In Spanish, we have a name for that: torre loca (meaning "crazy rook") I think "crazy rook" is also used in English, but I don't find so many links, so maybe there are other names for it or those I can find are a translation error

# Answer
> 2 votes
Sometimes I hear it referred to as a "poison piece," because it kills you if you take (consume?) it.

---
Tags: terminology, stalemate, perpetual
---


# Question
Title: Which opening requires the longest amount of chess moves?
For most openings that I play (e4 and d4 openings) I have observed that they take exactly 4 moves (e.g. Giuoco Piano Game without variation).

C50: Giuoco Pianissimo, Italian four knights variation takes 5 moves. The Van't Kruijs Opening (1. e3) takes less than 1.

Which opening requires the longest amount of chess moves?

## Edit

As I see I have been unclear, let me clarify. When I say two distinct openings, all I mean is a different name. For example, Ruy Loypez, XXX Variation is different from Ruy Lopez Ppening is different from Ruy Lopez, YYY Variation.

# Answer
> 6 votes
Here is one possible answer: there is an eco.json file available which is based on the *Encyclopedia of Chess Openings*. If you take the contents of that file and sort the openings by the length of the line leading to the named position, there is a unique winner, the 36 plies long *Ruy Lopez: Marshall, Main Line, Spassky Variation*:

```
{'c': 'C89',
 'f': '5rk1/5ppp/p1pbr3/1p1n3q/P2P2b1/1BPQB1P1/1P1N1P1P/R3R1K1 w -',
 'id': 3320,
 'm': 'e2e4 e7e5 g1f3 b8c6 f1b5 a7a6 b5a4 g8f6 e1g1 f8e7 f1e1 b7b5 a4b3 e8g8 c2c3 d7d5 e4d5 f6d5 f3e5 c6e5 e1e5 c7c6 d2d4 e7d6 e5e1 d8h4 g2g3 h4h3 c1e3 c8g4 d1d3 a8e8 b1d2 e8e6 a2a4 h3h5',
 'n': 'Ruy Lopez: Marshall, Main Line, Spassky Variation'}

```

---
Tags: opening
---


# Question
Title: What is the realistic depth in chess we can set in graphical user interface when we have hardware with 16 core processor with 32 threads?
I want know the depth we can set in 16 core processor and 32 threads time can be maximum set to 15 seconds. Please share your thoughts and ideas.

# Answer
If you want to search based on a time limit, you should be using iterative deepening search. That is: search to depth 1, then 2, then 3, etc. After you search to each depth level, check if you've exceeded the time limit (or are close to exceeding it).

This may seem inefficient but if you use a transposition table it actually gives the engine a significant boost since it can look at the best moves first on each iteration.
> 0 votes

---
Tags: computer-chess
---


# Question
Title: Are there any attempts at writing Stockfish MCTS?
As of time of writing, there is one major traditional engine using Monte Carlo Tree Search for its search algorithm - Komodo. The MCTS version of Komodo started out weak but gained strength quickly, and Komodo MCTS recently defeated Komodo AB (i.e. Komodo using the more traditional alpha-beta pruning) in the TCEC Cup 3. That indicates that MCTS is at least comparable to standard AB search.

Are there any attempts at converting Stockfish to MCTS search?

# Answer
> 7 votes
This is difficult to answer definitively as there is obviously no way to say that there isn't someone *somewhere* working on an MCTS version of Stockfish. However, as of the time of writing, there exists no official attempt to create an MCTS version of Stockfish.

While some forks of Stockfish, such as ShashChess and SugaR have MCTS-like modes, they differ from what you are looking for:

* One of these modes applies a simple neural network to determine `R` in Late Move Reductions in Stockfish's alpha-beta search.
* The alternative collects MCTS-like information for each root move by collecting the evaluation of every node visited in a standard alpha-beta search. This is not really MCTS as it only collects additional statistics on the same alpha-beta search function.

Komodo MCTS, which does use its own handcrafted evaluation function and a full-fledged MCTS search, is only competitive with the standard version due to the fact that its implementation of MCTS applies alpha-beta rollouts: i.e. the alpha-beta search used in standard Komodo is used to determine the expected win % for leaf nodes, and also as the *policy* to determine which nodes should be preferentially expanded.

The exact methods by which Komodo MCTS converts its alpha-beta score to an expected win probability, as well as the details in how alpha-beta searches are used to determine which node MCTS should expand, are all proprietary. As such, it's unlikely that implementing MCTS in Stockfish is anything close to trivial.

---
Tags: engines, stockfish
---


# Question
Title: Why does NCM show no progress for Stockfish when each new version has to beat the previous version?
NCM plays each Stockfish dev build 20,000 times against Stockfish 7. This yields an approximate Elo difference and establishes confidence in the strength of the dev builds. As of time of writing, one can see from the plot that Stockfish's strength hasn't really budged for a month: version 20190324-1637 had a performance of +217.95 +/- 3.73 elo relative to Stockfish 7, while the latest version 20190420-0634 is +221.52 +/- 3.79 elo. The gap is within the error bars.

(It's possible that this is sort of the expected performance increase in a month's time, but the latest version's results appear to be anomalously high. For example the next-latest version, 20190419-1533, is +218.61 +/- 3.77 and almost indistinguishable from the 20190324-1637 version.)

The weird thing is, for each version of Stockfish to be promoted to the "main version", it has to beat the previous version. All these new versions of Stockfish (that aren't non-functional changes) have to do this. If we look at the catalogue of Stockfish patches, we see patches such as:

> Author: protonspring Date: Tue Apr 16 23:10:53 2019 +0200 Timestamp: 1555449053
>
> Move pawnsOnSquares to Position (#2100)
>
> We can remove the values in Pawns if we just use the piece arrays in Position. This reduces the size of a pawn entry. This simplification passed individually, and in concert with ps\_passedcount100 (removes passedCount storage in pawns.).
>
> STC LLR: 2.95 (-2.94,2.94) \[-3.00,1.00\] Total: 19957 W: 4529 L: 4404 D: 11024 Elo +2.18 http://tests.stockfishchess.org/tests/view/5cb3c2d00ebc5925cf016f0d
>
> Combo STC LLR: 2.95 (-2.94,2.94) \[-3.00,1.00\] Total: 17368 W: 3925 L: 3795 D: 9648 Elo +2.60 http://tests.stockfishchess.org/tests/view/5cb3d3510ebc5925cf01709a

In other words this version of Stockfish defeated the previous one by ~2 elo. Why isn't this ~2 elo showing up in the NCM data? I know elo isn't transitive (i.e. if engine A beats engine B by 50 elo and engine B beats engine C by 50 elo, it doesn't mean engine A beats engine C by 100 elo), but this is just one patch, and there were plenty of elo-gaining patches that passed Fishtest. For NCM to show *no progress* for months, in spite of all these patches, doesn't make sense to me.

# Answer
> 4 votes
Fishtest tests proposed changes to Stockfish's code with SPRT to determine if they should be accepted. Broadly speaking, there are two types of changes which are tested in this way (non-functional changes do not go through Fishtest): simplifications, and changes which intend to gain strength - elo changes.

The crucial difference here is that simplifications (like the one referenced in the question) are tested for no regression, whereas elo changes are tested for an improvement: SPRT bounds of \[0.5, 4.5\] are used for elo changes and bounds of \[-3, 1\] are used for simplifications.

The vast majority of changes to Stockfish recently have been simplifications, and as such they are not expected to increase strength.

For example, the patch in the question is a simplification, and was tested with SPRT bounds \[-3.00, 1.00\]. The fact that it passed tells us that *there is a 95% chance that the change does not lose 3 elo*. If the test failed, we would know that *there is a 95% chance that the change does not gain 1 elo*.

We can't say anything more precise than this, because SPRT stops immediately as soon as there is enough evidence to accept either hypothesis and doesn't attempt to measure the elo change more precisely. Although an elo difference of +2.18 is quoted at STC, all we know is that the lower error bound on the elo gain is `>= -3.00`.

There is insufficient evidence to say that the change produced an actual elo gain of +2.18, and thus claiming that this simplification gains 2 elo would be misleading.

The small number of elo gaining changes is what results in Stockfish's slow progress at the moment.

---
Tags: engines, stockfish
---


# Question
Title: Why is 5. f5 so necessary in the Dzindzi-Indian Opening/Modern Defense: Pterodactyl, Beefeater Variation?
I have played a couple of games as black with this line. It is a simple plan: to put pressure on the weak c3 and c4 pawns.

This line is mainly known as the Dzindzi-Indian Opening, according to the comments and this video. It's also called the Modern Defense: Pterodactyl, Beefeater Variation according to chess.com.

```
[FEN ""]

1. d4 g6 2. c4 Bg7 3. Nc3 c5 4. d5 Bxc3 5. bxc3 f5

```

I have tried it while playing correspondence, so I have followed the move suggested by databases: 5. f5. This has had good results after quickly playing Qa5, trying to attack the weak pawns along with other minor pieces.

5...f5 **347**
2018 2403/2426/2709 30.3% 25.6% 44.1%

5...Qa5 **22**
2017 2359/2306/2586 50% 22.7% 27.3%

5...e5 **5**
2014 2370/2338/2418 40% 20% 40%

5...d6 **1**
2010 Steadman vs. Bosboom 0-1

*Chesstempo database for the position

I wonder what the reason is for taking away a tempo to play f5 while the plan is clear, at least as I play it: to profit from the doubled pawns by attacking on the queenside.

Is f5 played to avoid e4?

# Answer
You don't want a White pawn getting to e5, especially with a friend at f4. White can let you have a c-pawn if he can achieve such a central dominance.

Also, without f5 it is awkward to develop the Ng8 -- you notice none of the variations you show have Nf6. But now after f5, Nf6 will grip the e4 square. Thus White often plays e4 anyway!
> 5 votes

# Answer
By playing ...f5 you're trying to weaken the e4 push. This is the most important immediate thing to attend to. It's not like White's doubled pawns are going to run away anytime soon.
> 4 votes

# Answer
f5 has the aim to stop the e4 push. However, a "refutation" of the line is 1. d4 g6 2. c4 Bg7 3. Nc3 c5 4. d5 Bxc3 5. bxc3 f5 6. e4 fxe4 7. f3!; Here, if black captures in f3, then white has a strong attack due to the better development. Therefore, in his DVD series on the Dzindzi, GM Ron Henley suggests 7. ...e5!, but he doesn't consider the first choice of Stockfish, which seems very good for white: 8. Nh3! with the idea of Nf2 (ff 8. ... exf3 then simply Qxf3).
> 3 votes

---
Tags: opening, evaluation, modern-defense
---


# Question
Title: Why is c4 bad when playing the London against a King's Indian?
Recently I (rated ~1900 "classical" on Lichess) played the following opening: 1.d4 Nf6 2.Bf4 g6 3.e3 Bg7 4.Nf3 O-O 5.Nbd2 d6 6.c4

```
[FEN "rnbq1rk1/ppp1ppbp/3p1np1/8/2PP1B2/4PN2/PP1N1PPP/R2QKB1R w KQ - 0 6"]

```

Upon playing c4, the stockfish analysis goes from a score of 0 to a whopping -1.1, as if I've already blundered a pawn. I've noticed this in a lot of my games - when black avoids developing his queenside and putting pawns in the center, I'm tempted to play c4, planning Nc3, castling kingside, taking up space on the queenside and if black is passive, perhaps pushing for a central pawn break with c5. But in these situations stockfish usually strongly dislikes c4.

Why? Stockfish's response is usually suggesting black play c5 pretty quickly, but this allows d5 giving me a lot of kingside space instead, and I can imagine a nice eventual pawn break with e5. I'm perhaps not at a level where I should be focusing on the opening so much, but I feel like I'm missing a big strategic idea here.

# Answer
It may be to the fact that you are making his bad Bishop into a Monster. After 6...c5, 7. d5 Nh5! and the dark square bishop is free to roam.

```
[FEN "rnbq1rk1/pp2ppbp/3p2p1/2pP3n/2P2B2/4PN2/PP1N1PPP/R2QKB1R w KQ - 1 8"]

```
> 8 votes

# Answer
If you want to play c4 against the King's Indian, it's better to go "all in" by having your e-pawn on e4 (so playing a main line against the KID). With the pawn on e3 you're sort of dipping your toe in the water with c4. It's not nearly as effective.

There's also an important tactical reason for why c4 is bad (probably why Stockfish gave -1). After 6...c5, if you push 7.d5 then Black has 7...Nh5, attacking your f4-bishop and the hanging b2-pawn. You'll have to give up the pawn or settle for Black playing ...Nxf4 and giving you doubled pawns. You could avoid pushing d5 but then after ...Nh5 (again) your d-pawn is under heavy fire since it doesn't have any support from your c-pawn.

If your c-pawn were on c3 then the d4-pawn would have more support, and there would never be any issues with the b2-pawn hanging.
> 7 votes

# Answer
I don't think the problem is with any c4 in this type of position altogether. I think that if you go for a line like 5.c4 and 6.Nc3 your position is just OK.

The particular position you post is maybe a different story as the knight is a bit misplaced on d2 (this leaves the d4 pawn a bit exposed. Many of the moves suggested are right, and exploit this fact in one way or another.

I am surprised, however, by how much the chess community has changed! In both responses, the writers believed the engine's evaluation and tried to justify it. I'd rather think Stockfish is exaggerating here! For how long have you let it think? (Please beware of the use of computer analysis in the opening. When no tactics are involved, it can be quite misleading!) If we trusted machines for the opening, we would be playing 1.Nc3 all the time. But how many games have you seen with that move?

The line with 6...c5 pointed out by @Inertial\_Ignorance is strong, but I don't think Black is more than slightly better after 7.d5 Nh5 8. Qb3 Nxf4 9.exf4. By the way, you can also just play 7.Nb3 or 7.bxc5 instead continuing your development with a reasonable position.

One (correct) argument is that the sequence is bad as a whole as you'll never get anything more than equality, but I don't see any other way to play that leads to an advantage for White, with or without c4. With correct play, you will reach an equal position that is (maybe) a little more comfortable for Black
> 7 votes

---
Tags: opening, strategy, kings-indian, london-system
---


# Question
Title: Why is 3. Nc3 played in mainline of the Modern Defense?
After:

```
[FEN ""]

1. e4 g6 2. d4 Bg7

```

by far the most common third move is 3. Nc3. This goes against the principle of not blocking the c pawn with the knight as white, now of course principles can be broken but I can't see the benefit of doing so here.

The e4 pawn does not need defending, and if the aim is to stop 3... d5 then 3. c4 achieves this as well, then Nc3 can be played later.

So why is it not preferable to play 3. c4 before Nc3?

# Answer
3. c4 will likely transpose to a King Indian defense while 3. Nc3 will likely lead to a Pirc. 1. e4 players will prefer the more familiar Pirc positions.

The Modern Defense move order lets White decide the main position.
> 6 votes

# Answer
There is no such principle as "don't block your c-pawn". A c3/c4 pawn push is better in some positions and worse in others. What White intends is to develop his queenside fast, castle there and launch a kingside attack with his pawns, so c4 is out of the question if you want to play that plan.

Indeed, White would want to do the same thing against the King's Indian, the reason why he doesn't is that Black would not allow it! See for instance 1.d4 Nf6 and now 2.Nc3 is not done because 2...d5 would come, otherwise, if would be the best move!
> 3 votes

# Answer
It is just a matter of taste. White is playing a king pawn opening so with the pawn on e4 the principal of blocking the c-pawn does not apply. White simply doesn't want to play a King's Indian defense.

With Nc3 White has a lot of options:

* For one he can seek a more Dragon type game with the idea of Bc1-e3, Qd2, and h2-h4; often with f2-f3 being played.
* Alternatively, White can go for f2-f4 lines probably pushing e4-e5.
* Or White can play classically with Nf3 and Be2.

So overall a flexible developing move.
> 3 votes

# Answer
3.Nc3 saves a tempo by not pushing the c-pawn first, which could be important in some sharp lines. However, 3.c4 is equally as good, transposing from the Pirc into the King's Indian.

It really just depends on your preferences.
> 1 votes

# Answer
Carlsen used to play 3.Nf3 with the idea of 3...d6 4.Bc4 Nf6 5.Qe2 0-0 6.0-0, with Rd1 and e5 following. It is very easy to play with white because the attack is immediate, and solving the black issues on the board seems not to be that easy.
> 0 votes

---
Tags: opening, positional-play, modern-defense
---


# Question
Title: Why play Nb5 in this line of the sicilian?
After 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 why is 5. Nb5 the best move? The game usually continues 5. Nb5 d6 6. N1c3 a6 7. Na3 and it looks to me like whites knight on a3 is misplaced. What makes this line good for white?

```

      [StartPly "8"]

      [FEN ""]
      1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 e5 5.Nb5 d6 6.N1c3 a6 7.Na3

```

# Answer
The real reason why this is the main line lies in the many possible variations after 5.Nb5 and its alternatives. Any verbal explanation will at best be approximately correct. With that in mind, here is my take:

5.Nb5 is the variation that best keeps control of the weakened d5 square. If black achieves d5 its only strategic problem will vanish, so keeping control of d5 is whites main strategic objective. 5.Nb5 provokes d6, which makes it impossible for the Nc3 to be neutralised by Bb4. This Bb4 move is a problem if the knight retreats to f3 or b3. If the knight goes to f5, d5 is even immediately possible.
> 5 votes

# Answer
The knight has been recluded to the a3 square, with the move a6 and e5. while a6 may be a useful tempo, e5 is weakening. Meanwhile, the knight is going to e3 via c4, controlling d5. If black plays b5 to avoid it, then white ideas are based on the c4 break: in this case, the Knight can be recycled via c2.
> 3 votes

# Answer
The knight on b3 isn't doing much other than covering d4 which isn't a big deal. White has plans to reposition the knight to e3 and forcing d6 does block in the black bishop.
> 0 votes

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


# Question
Title: What are good openings for bullet chess?
It is evident that bullet chess has a different set of strategies from regular chess. It follows, therefore, that certain openings will be better or worse relative to their normal chess counterparts. Hikaru Nakamura covers some examples in his book "One Minute to Mate", but the coverage is very light. What are some good bullet chess openings that are particularly strong due to the nature of bullet chess?

# Answer
The best bullet players can and do play standard openings. The openings are theory because they *are* the best moves.

If you want to play something different, there are a few justifications. If you play certain moves all the time, you can often make the moves faster and gain time on the clock. Similarly, if you play something off-beat, you will most likely know some plans from the position and often have a better understanding than your opponent.

With that lead in, one of the simplest openings to play is to fianchetto both bishops, play `e3` and `d3`, and bring the knights to d2 and e2 (not necessarily in that order). There is very little going on in the first 8 moves, so you won't have to look hard for tactics. The downside is that you give your opponent a large space advantage.

The main plans of this opening are to develop all of your minor pieces and then decide to play either `c4` or `f4` depending on how your opponent has deployed his or her forces. You can castle (usually kingside) and then just play chess.

Personally, I have always had better success in online chess (especially bullet) playing standard openings. Play openings that you are comfortable with, and you will be able to take advantage of your whole sum of chess knowledge, as opposed to just utilizing bullet "tricks".

While it is beyond the scope of this question, one of the best ways to improve at bullet is to work on playing better and faster when both players have 10 seconds. Most games are won or lost in this time frame.
> 13 votes

# Answer
Openings you are **more familiar** with than your opponent, and in which it **makes a difference**¹. If you want to take advantage of it somehow, and not just “play better”.

Therefore I'd propose to go for *gambits* and very *open positions*, in an aggressive style. Especially not well-known ones². In these openings, being familiar with the ins and outs of the arising positions will give you a big advantage if your opponent isn't. On the contrary, in a closed game, tiny mistakes can be a lot harder to punish, especially in this time frame (i.e. you don't want to have so safe-but-small an advantage that the first slip you do in endgame will ruin it).

Therefore I suggest :

And for black :

* Budapest Gambit against `1. d4`.
* Elephant Gambit against `1. e4 e5 2. Nf3`.
* Petrov or Scandinavian defenses could be options too.

If you're ready to learn many more, you can delay them to later moves in most played lines, but that grows the repertory you have to master. You might want to have a look there.

¹ I'd argue Andrew's suggestion of fianchettos is way too passive for that, as your opponent has virtually no chance of doing a mistake against that. (I've played this system for a long time.)
² I'm not talking about Queen's gambit or the Najdorf, that is.
> 9 votes

# Answer
In my opinion, one must play an opening that one plays most often, as in bullet chess there is very little time to think. If you are receptive to go and learn a new opening, then I recommend Stonewall as it makes the game a very closed game while retaining a strong hold of the center. With black pieces, French Defence and Budapest Gambit serve as good openings.
> 6 votes

# Answer
To be perfectly honest, just play your regular openings. You know them the best, and consequently will be able to play quicker with them. I'm around 2400 online in 1 0 chess and this is the strategy I use if I'm feeling "serious" about my rating.
> 1 votes

# Answer
I played 1+0 some time ago and book openings were not something to consider a lot at my level (I had 2000 at 1+0 at chess.com).

However, it is slightly different if you play 1+0 (or 1/2+0) than e.g. 2+1, which is sometimes included in bullet time.

If you play 2+1, you can play the game as in blitz following the openings you know, but 1+0? well at this time control you may want to put your opponent in trouble.

It is common at 1+0 to offer even pieces just to win some time. Sometimes your opponent get nervous and to play weird opening making quick threats can be something to consider at a \[young\] non-master level.

```

[FEN ""]

1. e4 e5 2. Bc4 Nc6 3. Qh5 g6 4. Qf3 Nf6

```

The result is black can lose 5 seconds (as important as a pawn at a 1+0 game) whereas white has not a weak structure or serious troubles in development.

---

If you don't want to play weird openings you can try Budapest Gambit kindly openings. After 2.....e5 white may lose some seconds or fail not capture the pawn with advantage, and you can always finishing by materializing some traps as this one if your opponent doesn't know the theory.

```

[FEN ""]

1. d4 Nf6 2. c4 e5 3. dxe5 Ng4 4. Bf4 Nc6 5. Nf3 Bb4+ 6. Nbd2 Qe7 7. a3 Ngxe5 8. axb4 Nd3++

```
> 0 votes

---
Tags: opening, bullet-chess
---


# Question
Title: Should an arbiter claim draw at a K+R vs K+R endgame?
I was asked for first time to help at a non federated tournament for kids to arbitrate their games, played at 30 minutes with no increment time. It was a scholar tournament and they made mistakes as leaving checkmates in one, let the queen to be captured etc.

At one game both kids arrived to a K+R K+R endgame. There was not a way to quickly gain the rook and win the game and both kids had time. One kid claimed it was a draw. We were two arbiters (not experts, just two 1900 helping a bit at the club). We claimed draw.

Was it a correct decision or we should have left the kids play?

# Answer
You can declare a draw and in fact you are required to declare a draw but only after you have counted 75 moves by each side without a capture or a pawn move. This is according to the FIDE Laws of Chess article 9.6.2:

> 9.6 **If one or both of the following occur(s) then the game is drawn:**
>
> 9.6.1 the same position has appeared, as in 9.2.2 at least five times.
>
> 9.6.2 **any series of at least 75 moves have been made by each player without the movement of any pawn and without any capture. If the last move resulted in checkmate, that shall take precedence**

Of course the players are also free to agree a draw between them.

EDIT: blues makes the following comment:

> III.5.1 may also apply. If the arbiter agrees that the opponent cannot win by normal means, or that the opponent has been making no effort to win the game by normal means, he shall declare the game drawn. Otherwise he shall postpone his decision or reject the claim. This does not require 75 moves or fivefold repetition

I will answer that here since there is insufficient room in a comment to do so.

Guidelines III.5.1 almost certainly does not apply in this case. III.5.1 is not standalone. It is part of section III and is dependent on earlier parts of III.

Let's take a look.

> **Guidelines III. Games without increment including Quickplay Finishes**
>
> **III.1** A ‘quickplay finish’ is the phase of a game when all the remaining moves must be completed in a finite time.
>
> **III.2.1 The Guidelines below concerning the final period of the game including Quickplay Finishes, shall only be used at an event if their use has been announced beforehand.**
>
> **III.2.2** These Guidelines shall apply only to standard chess and rapid chess games without increment and not to blitz games.

First, according to the OP, the time control was all moves in 30 minutes, so a rapid time control and no increments mean it is possible that III applies. However according to III.2.1 these **shall only be used at an event if their use has been announced beforehand**. They were almost certainly **not** announced beforehand, else the two arbiters would have at least know of their existence and they appear not to.

Suppose they were announced beforehand. Then we come to:

> **III.4** If the player having the move has **less than two minutes** left on his clock, he may request that an increment extra five seconds be introduced for both players. This constitutes the offer of a draw. If the offer refused, and the arbiter agrees to the request, the clocks shall then be set with the extra time; the opponent shall be awarded two extra minutes and the game shall continue.

The OP in one of his comments seems to say that both players still had 25 minutes left. This would mean this does not apply. Nevertheless supposing the player did have less than 2 minutes left, the arbiters cannot apply this rule unless the player specifically asks for it. The arbiters are not allowed to help the players in any way and may not volunteer this information during the game. They may only make announcements informing all players **before** the game.

Continuing, we finally reach the part blues references:

> **III.5** If Article III.4 does not apply and the player having the move has less than two minutes left on his clock, he may claim a draw before his flag falls. He shall summon the arbiter and may stop the chessclock (see Article 6.12.2). He may claim on the basis that his opponent cannot win by normal means, and/or that his opponent has been making no effort to win by normal means

First, this can only apply if III.4 does not apply. The only way that can happen is if there are no digital clocks capable of being set with the required time and increment. If such clocks are available then III.4 applies and III.5 does not apply.

Suppose, however, that all the previous counterfactual "if onlys" apply then III.5 can only apply if the player also knows the rule and makes the specific request in the correct manner. Again, even if the arbiter knows the rule he may not help the player by volunteering the information.

Hence my original conclusion that - Guidelines III.5.1 almost certainly does not apply in this case.
> 25 votes

# Answer
It is not a drawn position according to the rules, since there is sufficient mating material. It may be a draw from the point of view of endgame theory, but given players who make lots of mistakes, it wouldn't be all that surprising for one to lose to a tactic.

I would let them play until the player who wanted a draw can claim it based on the 50-move rule or threefold repetition, or someone runs out of time or the game ends some other way. (Were they keeping notation? If not making a proper claim could be difficult, although an arbiter who witnesses the game could rule it a draw after 75 moves or fivefold repetition. Also note that USCF rules allow the arbiter or a deputy to count moves, if requested, for a 50-move claim under sudden death.)

That said, for a "non federated kids tournament", I suppose you may have some leeway, so I wouldn't really fault you for ruling it a draw.
> 16 votes

# Answer
It's better to let them play it out a bit and ideally only draw once reaching 50 moves. But if one of them is low on time (and their opponent is clearly just trying to flag them) then you should claim the draw.
> 6 votes

# Answer
It is difficult to say what the exact rules should be if you aren't affiliated with a group that publishes rules for such situations. But I think your actions in this case were reasonable.

USCF rule 14H used to state that a player with less than two minutes on the clock (with no delay or increment being used) could make a claim of insufficient losing chances. Officially, that rule is no longer in effect, although a tournament is still allowed to use it as a variation without announcing it in advance.

If this variation is used, then rule 14I4 specifically states that rook vs rook should be a draw unless it is a position where there is a quick win. In general, if a class C player with ample time would not reasonably lose the position against a master, then the draw claim would be upheld, under this variation. This is regardless of the actual strengths of the players involved or how little time is on the clock.

Since there were more than 2 minutes on the clock ("both kids had time") technically this variation could not have been invoked. However, an attempted draw *claim* also constitutes a draw *offer*, which the other player may accept even if the claim is not upheld. According to your comment on another answer, you asked the other player if they agreed with the draw, and they seemed happy with it. That would be good enough for me. If neither player wanted to play on, there would be little point in forcing them to shuffle the pieces around for 50 moves. It's possible that novice players would not even be aware of the possibility of simply offering a draw.

The part of the USCF Official Rules of Chess book which contains the rules is now available online, by the way. I found it here.
> 5 votes

# Answer
Relevant FIDE rule, appendix G.5:

> If Article G.4 \[a player may claim extra time for both sides\] does not apply and the player having the move has less than two minutes left on his clock, he may claim a draw before his flag falls. He shall summon the arbiter and may stop the chessclock (see Article 6.12 b). He may claim on the basis that his opponent cannot win by normal means, and/or that his opponent has been making no effort to win by normal means.

Similar to the USCF rule cited by D M, technically this can only be invoked if the claiming player has less then two minutes on their clock.
> 3 votes

---
Tags: rules, tournament, claim-draw, tournament-directors
---


# Question
Title: What should the arbiter and what should have I done in this case?
Recently, an official (FIDE-rated) tournament was held, where I participated.

In the last round – which was the most critical one – I was black and my opponent white. In the middle of the game, they started making strange sounds, which clearly disturbed both the nearby boards and me.

At first, I mentioned that they were disturbing. Since they wouldn't listen, I called the arbiter. In all 4 cases, the arbiter warned the user like this:

> \<Player name\>, could you please stop doing this, since you are disturbing your opponent?

In addition, when I offered draw, here's what my opponent replied:

> If the game were drawn, then I would offer it first to you.

* **What should the arbiter have done**? At least, I'd expect to have a punishment in the clock (e.g., +2 minutes for me, -2 for them). It is well-defined in article 11 of Fide Laws of Chess (emphasis mine):

> 11.5 It is **forbidden** to **distract** or **annoy the opponent** in **any manner whatsoever**. This includes unreasonable claims, *unreasonable offers* of a draw, or the introduction of a source of noise into the playing area.
> 11.6 **Infraction** of any part of Articles 11.1 – 11.5 shall lead to **penalties** in accordance with Article 12.9.
> 11.7 **Persistent refusal by a player to comply with the Laws of Chess shall be penalised by *loss of the game***. The arbiter shall decide the score of the opponent.

And I suppose that this behaviour is persistent.

* **What should *I* have done**? I ended up losing the game and, while I could end being 2nd, I ended up being 3rd! Could I make an appeal to another arbiter or even the chief?

# Answer
First, we cannot tell you what the arbiter should have done because we were not there and certainly don't have all the facts. We only have your version of events. What you say was very disturbing may not have been perceived as so disturbing to others there at the time. We weren't there, so we just don't know. We can't judge.

As to what you should have done, you did the right thing by bringing the disturbance you suffered to the attention of the arbiter. If the arbiter took no action beyond issuing a warning you could have made another appeal to the arbiter during the game for more robust action.

At the end of the game you could also have refused to sign the scoresheet and instead raised the issue again first with the arbiter and then the chief arbiter. If this failed then you could have lodged an appeal with the appeals committee for the tournament. FIDE rated tournaments are required to have an appeals committee to which you can appeal during the tournament. This committee is usually composed of players in the tournament and disbands when the tournament finishes.

Finally, if you took all those actions and still did not get a satisfactory answer you could appeal to your national chess federation. You could probably still do that now but if you didn't make the previous levels of appeal and complaint you are unlikely to get any satisfaction.

Currently there is a high level women's tournament (candidates for world championship) taking place in Kazan in Russia which has a problem with noise from a band playing music outside. Some of the players have earplugs and are not being disturbed by it others do not and are being disturbed.
> 18 votes

# Answer
At this point you should report the Arbiter to FIDE and if applicable the USCF. You could even try to get the result of the game changed.

They should have implemented Article 12.9 penalties followed by *loss of game* if it continued.

Now that you have read the articles, you probably see that you could have pressured the Arbiter to implement the rules.

\[Unfortunately, the world is full of people that are either incompetent or lazy and therefore don't do their jobs; forcing competent people to learn all kinds of area's in life just to be able to hold the incompetent accountable or simply get the service they need.\]
> 8 votes

---
Tags: rules, tournament, arbiters
---


# Question
Title: What are the rules of chess in a nutshell?
I believe the question How to start learning chess? is actually two questions only one of which is a duplicate. This question is a fixed up version of it which asks only the other one of those questions.

Would it be possible to explain the rules of chess in a nutshell? A clear short description of the rules is nowhere to be found but I'm sure it can be explained very simply.

# Answer
Yes, the rules can be explained in a nutshell as follows. It uses some ideas I originally wrote at https://en.wikipedia.org/w/index.php?title=Chess&oldid=649489454.

Chess is a 2 player game. It starts with the pieces arranged like in the following image.

One player moves only white pieces and sits on the side of the board where the white pieces start. The other player moves only black pieces and sits on the side where the black pieces start. Which ever player moves the white pieces starts first.

Chess without some of the extra rules works as follows. Each player on his or her turn can make any move as long as it satisfies the following conditions:

* It's a move of one of the following forms:

+ Normal move

    A normal move is a move where a player moves one piece of their own color under the following conditions:

    - The piece he or she moves is the type of move for that type of piece which is as follows:

        * The king moves one square in any direction.
            * The rook can move any number of squares along any rank or file.
            * The bishop can move any number of squares diagonally.
            * The queen combines the power of the rook and bishop and can move any number of squares along rank, file, or diagonal.
            * The knight moves to any of the closest squares that are not on the same rank, file, or diagonal, thus the move forms an "L"-shape: two squares vertically and one square horizontally, or two squares horizontally and one square vertically.
            * The pawn may move forward to the unoccupied square immediately in front of it on the same file without capturing, or on its first move it may advance two squares along the same file without capturing; or the pawn may capture an opponent's piece on a square diagonally in front of it on an adjacent file, by moving to that square.
        - The piece stays the same type of piece unless it's a pawn moving to the 8th rank in which case it stays the same color and can get promoted to anything except a king. The promotion is not restricted to captured pieces. The pawn must get promoted if it reaches the 8th rank.
        - The piece may not go through another piece unless the former's a knight.
        - The piece captures another piece if it moves there but captures nothing if it moves to an empty square.
        - The piece may not capture a piece that's its own color.
    + Castling move

    A Castling move involves the king and a rook where the king moves two squares along the rank directly towards one of the rooks, then that rook moves over the king to the square that the king crossed over under the following conditions:

    - Neither the king nor the rook it's castling with ever moved before.
        - There are no pieces between the king and the rook it's castling with.
    + En passant move

    When a player moves a pawn 2 squares then on the very next move, the other player moves their pawn diagonally forward 1 square to the square that pawn moved through, capturing it in the process, the latter is said to be doing en passant. Note that the pawn does not move to the square of the pawn it captured in en passant.

A square is said to be under attack for one player when the other player has a move to that square satisfying the first condition. When the king is under attack, it's said to be in check.
* He or she may not make a move that leaves or puts his or her king in check.
* The king may not castle into check, out of check, or through check.

You win if you check mate your opponent. That is, after your turn, your opponent is in check and doesn't have a legal move. If after your turn, your opponent is not in check and doesn't have a legal move, it's called stalemate. Stalemate is one of the ways for the game to end in a draw.

There are also extra rules. Some of them are very clear and considered a universal rule of chess. Others are unclear how people should play in casual games but are clear in a certain type of tournament. I'm not absolutely completely sure of what they all are. Some of the clear ones are

* The 3 fold repetition rule states that if you go into the same state from the same other state a third time in the game, a draw is declared.
* One player can forfeit the match by resigning. It usually happens when they see that their opponent has a forced win.
* A draw is declared when both players agree to a draw.

Sometimes people also play a casual game of chess with a clock. People also sometimes play a variant of chess like crazyhouse chess but when they're doing that, they're said to be playing a different game which is not chess and are not said to be playing chess. Sometimes one player gives the other player permission to leave and not finish the game. Sometimes one player gives the other player permission to take back moves.

For a certain type of FIDE tournament with a certain rating, the rules are as follows:

* After both players complete 50 moves with nothing getting captured and no pawns moving forward, a player can claim a draw.
* If 75 moves have been completed without anything getting captured or any pawn moving forward, the game must end in a draw unless the last move is a checkmate.
* Both players play with a clock. Each player has 90 minutes for the first 40 moves plus 30 minutes for the rest of the game and an additional 30 seconds per move.

Sources:
> 0 votes

# Answer
The definitive guide to chess is given in the FIDE Laws of Chess. The game itself is defined by the first five articles and this is short.

There are many more articles, appendices and even guidelines in the FIDE Laws of Chess which cover over-the-board competition rules and practices but these are not required for a basic understanding of the game, only for tournaments.
> 6 votes

# Answer
How to win: preventing the opponent's king from moving while attacking it. This is a *checkmate*.

That's the goal of the game. The rest of the rules just relate to how each piece moves.

King: Can move one square in any direction.

Queen: Can move any number of squares in any direction, but can't jump over pieces in the way.

Bishop: Can move any number of squares along any diagonal it's on, but can't jump over pieces in the way.

Rook: Can move any number of squares horizontally or vertically, but can't jump over pieces in the way.

Knight: Can move in an L-shape. 2 squares horizontally and one square vertically, *or* 2 squares vertically and one square horizontally. It *can* jump over any pieces in the way.

Pawn: Can move one square forward, and has the additional option of moving 2 squares forward if it's on its starting square. However, it captures enemy pieces by moving one square *diagonally* in either direction. The pawn is unique in that it captures and moves differently (unlike all other pieces). In addition, if the pawn reaches the end of the board it turns into a queen, rook, bishop, or knight (your choice).

Also, the game could end where no one wins, a tie or *draw*. This can happen in a variety of ways:

* Both sides only have a king left.
* Neither side has any material left that's sufficient to possibly make a checkmate. Any example is one side having a king and knight vs a lone enemy king.
* A position has been repeated three times. This is called a three-fold repetition.
* One player offers a draw and the opponent accepts.
* Stalemate: one side has no moves left because his king is trapped and the rest of his pieces have either been captured off the board or cannot move. This is very similar to a checkmate, except that the trapped king is *not* being attacked.

I've left out some rules, but this is the meat of it.
> 3 votes

---
Tags: rules
---


# Question
Title: What is the reason (if any) for 1.e4 c5 2.Nf3 d6 3.Nc3?
As title above, what is the point of playing 3.Nc3 (before d2-d4) after 1.e4 c5 2.Nf3 d6? Compared to the “normal” 1.e4 c5 2.Nf3 d6 3.d4?

```
[fen ""]

[Variant "Standard"]
[ECO "B50"]
[Opening "Sicilian Defense"]

1. e4 c5 2. Nf3 d6 3. Nc3 { Less common move } (3. d4 { Usual move })

```

# Answer
It basically just stalls for a move before 100% committing to the open Sicilian. For example, suppose you were playing White and hated facing this Sicilian (1.e4 c5 2. Nf3 d6 3.d4 cd 4.Nxd4 Nc6). You could use the move order you described and after 3.Nc3, only play 4.d4 if your opponent doesn't play 3...Nc6. If they do play 3...Nc6, then go for some Closed Sicilian.

Also in online bullet some people have done the 3.Nc3 move order against me because it takes half a second to realize what's happening and then play 3...Nf6 instead of 3...cd.
> 7 votes

# Answer
If White is not willing to play a Maroczy formation (with c4), then Nc3 will eventually be played in almost any variation. Black has no clear way of preventing d2-d4 on the next move (3...e5 kind of sucks)

On the other hand, White may want to wait for Black's move before deciding whether to push d2-d4 or maybe go for a different variation against certain Black's responses (for example a closed Sicilian after 3...e6 4.g3
> 5 votes

# Answer
Najdorf players will have to go either 3. ...Nf6 or 3. ...a6. After the latter, White may make a move after which he deems ...a6 sligtly premature, such as 4. g3 (without saying that this will lead to an advantage for white over the Open Sicilian). I played 4. a4 once and got a good position after ... Nf6 5. e5 dxe5 6. Nxe5 Nbd7 7. Nc4 Nb6 8. a5 with a bind on the Q-side. After the former, there is 4. e5!? as well which is more dangerous than it looks and can easily throw an unprepared opponent off guard. The line is a specialty of 2700 player Mamedov.
> 2 votes

# Answer
Does it make sense though if white hates the sicilian 1. e4 c5 2. Nf3 d6 3. d4 cd 4. Nxd4 Nc6? Usually this move order leads to some Rauzer system after 5. Nc3 Nf6. The move order with 4... Nc6 gives White just the extra option to play some kind of Maroczy bind, and after 1. e4 c5 2. Nf3 d6 3. Nc3 Nf6 4. d4 cd4 5. Nc6 White ends up in the Rauzer anyway. I guess some people play 3. Nc3 against 2... d6 only, because they are playing it against 2... Nc6. After 1. e4 c5 2. Nf3 d6 3. Nc3, Black has no much additional options (except maybe 3... a6). After 1. e4 c5 2. Nf3 Nc6 3. Nc3 White manages to avoid the Sveshnikov, since there is no useful waiting move for black which still leads to Sveshnikov.
> 1 votes

# Answer
It avoids the Kalashnikov and the Sveshnikov
> 0 votes

# Answer
I sometimes play 3.Nc3 as it gives an option of against 3...a6, 4.e5 which leads to the kind of tedious positions I enjoy :) instead of some Najdorf. There are a lot of these kind of funny options for white players. For example 1.e4 c5 2.Nc3 Nc6 3.Nge2 used to give me some headaches as a sveshnikov player because 3...Nf6 is not what I was looking for against the closed sicilian, but there is still the possibility of white going 4.d4.
> 0 votes

---
Tags: opening, sicilian-defense, 1.e4
---


# Question
Title: Engine not necessarily playing strong but "attractive"
Does anyone know a chess engine that is not programmed to be as strong as possible, but to play "attractive" chess ?

The program should have an aggressive style and play for mate attacks, even if the attacking moves are not quite optimal. Or at least, the program should trade some panws early to avoid very closed positions which tend to take an eternity between engines to be finished.

On the other hand, the program should not play too weak. The rating should at least be about 2000 Elo.

Does anyone know such an engine ?

# Answer
Many engines have adjustable parameters, which allow to alter their playing style. If you mess around it a bit, you can create whole 'engine personalities'... Here, for example, someone though it interesting to create a personality called, the Komodo Kinghunter. Apparently, it does exactly what you are looking for - plays aggressively and not necessarily optimally. Note that I have not tested it myself.

It's different for different engines (I remember most of these at least used to be configurable in stockfish) and graphical interfaces, but some typical factors one can usually twiddle with (at worst by going to source code and recompiling) are:

**Contempt Factor**

> The Contempt Factor reflects the estimated superiority/inferiority of the program over its opponent. The Contempt factor is assigned as draw score to avoid (early) draws against apparently weaker opponents, or to prefer draws versus stronger opponents otherwise.

Additionally, if the engine has high contempt for its opponent, it might engage in more attacking style.

**Pawn structure**

> Pawn structure is a term used to describe the positions of all the pawns on the board, ignoring all other pieces. Pawn structure encompasses a broad range of ideas, from the general shape of the pawns (such as closed or open) to specific characteristics of individual pawns.

So here there's a wide range of things to change engines evaluations for - double pawns, passed pawns, general structure, exchanges etc.

**Mobility** A factor for how much the engine will value the piece mobility - I suppose more mobility leads to more attacking and unpredictable positions.

**Aggressiveness** Self-explanatory; allows to make the engine more or less aggressive.

**Cowardice** Self-explanatory; allows to define how defensive towards its own king the program should be.

Source for quotes

**EDIT: I was made aware (per Student T's comment), that the engine I initially posted below is not attractive at all and in fact a clone of Rybka. I guess it was too good to be true!**

If you are reluctant to do all this fiddling yourself, here's an engine which (again, I have not tried it myself, so cannot substantiate these claims in any way):

> Thanks to its finely tuned positional vision, Vitruvius shows a readiness to sacrifice a pawn or two, the exchange and sometimes even a whole piece, for purely positional compensation.

And named among its strengths:

> Playing strength above the 3100ELOmark; Detects and exploits zugzwang positions; Very human and speculative approach to the game

Also of interest: this Vitruvius article

Unfortunately, it is not free.
> 7 votes

# Answer
If you increase Rybka 3 Dynamic's contempt setting, it sacrifices more and more material in attractive style.

The Fritz GUI (sold with Rybka, Komodo, Houdini, Junior, Shredder et al) includes a King's Attack slider in its Handicap and Fun dialog. The Fritz 10 engine in particular avoided closed positions like the plague, and often played for mate. It had an 'aggressive' parameter.

Chess Tiger and Gambit Tiger (Chessbase or Lokasoft) had a "Suicidal" option under their Gambit Level parameter.

Junior 7 had a 'sacrifices' parameter.

Deep Sjeng 1.6 comes with gambitkitten, redshift and Tal personalities.

Someone created a Dissident Aggressor personality for Zappa Mexico which is apparently quite wild.

TheKing (a.k.a. Chessmaster) plays for mate even on its default settings.

Amyan has a kinghunting parameter.

Tao 5.6 tends to go for very complex positions with multiple pieces en prise.

The old DOS program Chess System Tal had an attractive style with lots of sacs.

Spark 1.0 and Fruit 2.3.1 had a King Attack parameter.

The Kinghunter personality for Komodo only worked for version 1.0, and they changed the parameters after that.

I think in general the programmers tried to make these engines both strong and aggressive. All of these (with the exception of Chess System Tal) are at the level of an International Master or higher. Engines below that designed to have a somewhat attractive style would include: Der Bringer, HeavyChess, Homer, Monarch and Trappy Beowulf.

Another thing you could try is loading some of Chessbase's weaker engines, and increasing the King's Attack slider in Handicap and Fun. Inmichess, Exchess, Comet and Capture R01 were all in the 2000-2400 range, and were sold by Chessbase in their Young Talents package.
> 5 votes

# Answer
I have created such an engine at https://www.apronus.com/chess/romantic-chess-variant.htm

It has been modified to allow pawn promotion to knights only and to treat pawns very lightly when assessing the material balance. In fact, this creates a chess variant which I called **Romantic Chess** because it is meant to discourage playing for a better endgame as a winning strategy, effectively promoting direct mating attacks as the only realistic way to win the game.
> 0 votes

---
Tags: engines, aggressive-play, attack
---


# Question
Title: Is it acceptable to pair a player with the same colour three times in a row?
A few months before an official national tournament is held, an announcement is published, which contains information about specific rules (e.g., no draw offers until the 30th move), etc. One thing that caught my attention was that a player **can't have the same colour for 3 consecutive rounds**.

Yet, in the last round, I played Black and my opponent White. After the end of the game, I realize that my opponent had taken White 3 times in a row. Swapping colours was also impossible since I was Black in the last 2 rounds.

Can the result actually be changed? Or should the game be replayed?

As I am not an arbiter, I'd also like to ask whether there is an option in Swiss Manager (the pairing program used) not to allow players to get the same color 3 times in a row?

# Answer
> 9 votes
> Lodging an appeal also came to mind that time. However, can the result actually be changed?

No. Only in extreme cases such as cheating can the result be changed.

> Or should the game be replayed?

No. There is no reason why the game should be replayed.

> In addition, as I am not an arbiter, is there an option in Swiss Manager (the pairing program which was used to make the pairings) not to allow players get the same color 3 times continuously?

Swiss Manager uses the JaVaFo pairing engine written by FIDE. The pairing engine implements the FIDE defined pairing rules. As far as I know (I am a FIDE arbiter) the only pairing rule that can be overridden is the one which says that a player who has already had a voluntary bye can also be given a compulsory bye in a later round given an odd number of players. In my experience this is never done.

> **In the last round**, I played with Black and my opponent with White.
>
> After the game, which I unfortunately lost, due to the lack of opening preparation, I realized that my opponent had taken White 3 times in the 3 last rounds. Playing with opposite colours was also impossible, since I had White 2 times continuously. In addition, I had played with most of the players which were up to the 10th position, so I couldn't find anyone else to play - maybe this is an exception?

In the FIDE Handbook the rules for Swiss pairing are given in the section Basic rules for Swiss Systems.

Your case is covered by these two rules.

> **f** For each player the difference between the number of black and the number of white games shall not be greater than 2 or less than –2.
> **Each system may have exceptions to this rule in the last round of a tournament**.
>
> **g** No player shall receive the same colour three times in a row.
> **Each system may have exceptions to this rule in the last round of a tournament**.

In the last round of a tournament the requirement to allow the highest placed players to play each other in the interests of having clear winners and major places decided fairly takes precedence over most of the other rules. The rule which says that two players who have already played in an earlier round cannot be paired against each other again takes precedence over all other rules and cannot be broken.

# Answer
> -1 votes
Unfortunately there's nothing you can do once the game is over, even if pairing rules were violated. In some tournaments you can talk to the TD after pairings are *posted*, but in FIDE tournaments pairings might be final once they are posted (if memory serves).

In rare cases you could lodge an appeal with an appeal committee, but most tournaments don't have these.

---
Tags: tournament
---


title: Leela Chess Zero - UCI engine

text:
# Question
Title: Leela Chess Zero - UCI engine
What is current use status of Leela for practical player? Is it already working well as UCI? Could anybody give some insight on strength with various thinking times, especially in analysis mode? As leela uses different thinking process, I must ask also for multiPV search. Is the speed down of many PVs still as devastating as with other engines?

I have desktop with 6x3.2Ghz CPU. As graphics card like RTX2080ti is 'just' around 1300€ with good use outside of chess too, I wonder, what performance change would it mean.

With mentioned hardware, how long would approximately leela have to think to compare to Stockfish?

Stockfish 0.1s Stockfish 1s Stockfish 10s Stockfish 1min Stockfish 10min Stockfish 1hour

# Answer
> 6 votes
Lc0 is fully compatible with UCI. It's strength depends a ton on what hardware it's being run on. On any hardware (tested down to Raspberry Pi), it will be superhuman (over 2900 elo). With a RTX 2060 ($200ish) it should be roughly even with SF on 8 cores (although you may need to mess with settings a bit to get it there). A 2080ti puts decently (20 or so elo) ahead of 24 cores of SF. The current MultiPV mode is only a display tweak. It isn't weaker, but it doesn't give as good analysis of the non-primary lines. If you have more questions, the best place to ask is probably the Lc0 discord.

# Answer
> 6 votes
Can't comment on hardware but will say something about Leela's strengths and weaknesses -

If you look through the games from the TCEC superfinal, sometimes Leela is brilliant. For example in this position from game 61:

```
[fen "r1bbnr2/pp1n1q1k/3p4/2pPp1pP/2P1PpP1/2NQ1N2/PP2BB2/2KR2R1 w - - 10 26"]

```

Stockfish (White) evaluated this as +0.63, while Leela was at -2.01. From the human point of view, I suspect most will prefer Black. That's because White has nothing on the kingside while Black is more capable of playing on the queenside. The game proved Leela right - it took a lot more moves for Stockfish to realize it was inferior, and even more moves after that for Stockfish to resign (it is a fantastic defender), but the fact that Leela saw it was superior so much earlier than Stockfish is very impressive. There are many similar games from the superfinal - Leela seems very capable of outplaying Stockfish positionally, often converting a Stockfish advantage into one of its own, even if the game eventually ends in a draw.

Another advantage of Leela is multi-PV. MCTS engines get this for free, while Stockfish (which runs on AB) needs to invest computational power. If this matters for you then that's an additional advantage for Leela.

However the infamous "Leela blunder" is still a thing. Take this position from game 81:

```
[fen "4rr2/2pb2bk/1p1p4/2nP3P/p1P1p3/P1N1Bq2/1P3N2/1K2Q1RR w - - 2 26"]

```

Leela just played 25...Rae8 and showed a +0.67 eval. It thinks its position is inferior, but not by that much. Its principal variation went 25. .. Rae8 26. h6 Be5 27. Rg7+ Kh8 28. Ka2 Rf7 29. Nfd1 Nd3 30. Qh4. Stockfish had the same moves, but saw that 28. Qg1! wins, and its eval shot up to +7.68 one move later. Leela remained blissfully unaware until Stockfish played Qg1, and resigned shortly afterwards. Stockfish virtually never makes this kind of one-move blunder.

Another problem with Leela is that it doesn't seem to defend very well. When Stockfish loses, it defends grimly and it takes a long time for Leela to grind a win. On the other hand when Leela loses, it often implodes. In the ongoing TCEC Champions bonus, its loss to Houdini 3 (!!) is illustrative. Houdini 3 is an engine many years old, rated hundreds of elo below Stockfish (and ostensibly Leela). But Leela hated the starting position so much it managed to lose. Comparatively you would need to play hundreds if not thousands of games before Stockfish loses to Houdini 3.

Finally a noticeable weakness of Leela's is that it isn't very good at beating inferior opponents. For example in the ongoing TCEC Champions bonus, which includes engines from many years ago, Leela is performing worse than 1-year old versions of Stockfish. In this, Leela is kind of similar to Petrosian - it doesn't win many games, but it's good in match play.

In the end, I think Leela is inconsistent. In some positions it's much stronger than Stockfish, and in others it's just worse. As a practical player, I'd say use both. Their relative strengths and weaknesses should be pretty apparent. As a heuristic, trust Stockfish if the position is highly tactical, or if it's an endgame. Otherwise trust Leela (but run Leela's principal variation through Stockfish to eliminate the "Leela blunder").

**EDIT:** Will probably expand on this later, but GM Matthew Sadler wrote a piece on the relative differences between Stockfish and Leela based on the 15th TCEC superfinal which you might find interesting (especially games 43/44) In a nutshell, Stockfish is comfortable going to a slightly inferior endgame and defending endlessly, while Leela hates that playstyle and prefers to seek active play.

---
Tags: engines, leela
---


# Question
Title: What are the benefits of learning to play chess as an adult (30s) if any?
I played chess when I was a child, but never got into it seriously (I didn't know it was possible at that age). Nowadays I'm playing regularly as a hobby and I'm interested in how this can affect my performance in other aspects of my life (specially in my job as a mathematician and a computer scientist).

Now I know it is highly beneficial to play chess as a child but I wonder if there is any research showing any benefit from learning chess as an adult (it's obvious that professional players and even amateur players are intelligent and have developed amazing mental skills... but they usually start playing at an early age).

Also, what different approaches could an adult take to learn chess? (if there is any research about it).

# Answer
> 7 votes
The benefit I like the most (I'm almost 60) is that it prevents, or slows down the onset of, Alzheimer's disease.

http://www.nytimes.com/2003/06/24/opinion/checkmating-alzheimer-s.html

http://gambit.blogs.nytimes.com/2010/12/07/can-playing-chess-prevent-alzheimers/?\_php=true&\_type=blogs&\_r=0

# Answer
> 7 votes
I think you are asking the wrong question. There's been recently a lot of (horrible?) marketing relating chess to Alzheimer's disease prevention, abstract reasoning skill improvement and so on. While this is all great, and very interesting from a scientific point of view, I'll say it's irrelevant!

The reason for that is that nobody plays chess because it's good for them. People play chess because they enjoy it, regardless of whether it serves them for any further purpose or not. By the way, pretty much any hobby you can think of has some type of benefit, and by choosing chess, you are therefore harming yourself in some way! The same principle applies to people who go to the gym. Either you enjoy your training our you will eventually quit.. And if you enjoy your training, then why do you need it to be beneficial?

With regards to the "which approach to choose for learning", just forget about research! If your goal is to play better chess, no scientist in the world can give you the domain-knowledge of an actual experienced chess coach... But you don't even need to hire a coach at all! Just learn by doing! Play a few games, analyse them (by yourself, not with a chess engine) and if you want to train some specific aspect, the best thing you can do is focus on the ones you will actually enjoy training!

In summary, chess will have an impact on your intellectual skills. But you have to achieve that as a side-effect, not as a target

# Answer
> 2 votes
From my own expierence , I started learn chess in my 50's. I also have dyscalcula (fancy word, it just means I don't visualize numbers so they get jumbled up for me, like how a dyslexic gets when they try to read words ). Chess is teaching my to watch the entire board, note how my actions can affect the actions of another, also notice how one action can have far-reaching consequences, like playing the wrong chess piece the wrong way (kinda like the chaos theory! ).

It helps me to understand that if I want to win, I have to look at the big picture (opponents set up, potential moves, can they check me , my set up , my potential moves, can I check them ) all at the same time, and on top of that, it's never the same game twice so I can't play on memory, I have to adjust every single time.

.......AND it's great fun too!! Just my two cents!

# Answer
> 1 votes
My case is a bit particular as I have Asperger Disorder, but I returned to chess as an adult after leaving it at 10 years old and I could say it might have saved my life. I would say I might not have graduated without chess. It improved my concentration when studying for exams, but it also taught me not to be so impulsive, which has helped me in most facets of life.

---

About your particular case, as mathematician you might improve your speed in calculus, especially if you do tactics exercises (a needed step, answering your second question), as well as have some other medical benefits like those related to Alzheimer's.

Understanding positional chess and strategy may also encourage your brain to better solve abstract math problems.

It might be positive for your profession and help you not to lose capabilities, as, note it, most of Science's extraordinary discoveries and works are done at a young age (around 25/30) and we all lose capabilities with age.

Also, if you reach a level to compete you can go to a club and socialize, which is always nice for health and happiness.

So if you like and enjoy the game, be sure it has some benefits for your brain and your health in general.

# Answer
> 0 votes
I don't know the answer to this question. However, I believe you might have made a wrong assumption about it being beneficial to play chess as a child so I'll write what I have to say about it. What does it mean to say it's bad to play chess as a child? That's very vague. I think it may be harmful to gain too much experience with chess before the age of 5 as I will explain later. People sometimes make mistakes. We don't know what's meant by "It's beneficial to play chess as a child." Even if we can determine what is meant, it's probably still only a theory that we cannot be absolutely certain of.

According to https://www.inc.com/bill-murphy-jr/science-says-were-sending-our-kids-to-school-much-too-early-and-that-can-hurt-th.html, students generally learn better from school when they're older. This too is probably only a theory. That might just be because when students start younger, they generally need longer to learn the basics and the teacher might move on from the basics before they're ready. However, I'm not sure it's not the case that there is also a slight tendency for students to sometimes misinterpret what they learned because they learned it too young and then later have trouble unlearning their misinterpretation and some people really are better off without the extra early learning of concepts than with it.

In one episode of the TV show "My 600 lb life," the overweight patient at the time she was 5 her parents or one of her parents kept saying "You're too fat. You can't have it," meaning dessert and she thought it was a punishment for being fat and got very depressed and kept on eating more to get her mind off the depression. It's probably because unconsciously, it can be deduced from the fact that she got a punishment that she did something wrong. An older person in that situation if their parents said something like that for the first time when they were older would probably figure out that it wasn't a criticism and tolerate that comment really well. That's probably how the parents of that patient thought of it and they probably didn't realize that she was too young to be able to figure out what they really meant by what they were saying. She probably thought they were thinking like the person who had his World of Warcraft account cancelled in the YouTube video Greatest freak out ever (ORIGINAL VIDEO). For her, she probably would have been so much better off without the early learning than with it.

Similarly, the article Too Young for Chess gives me a probable reason to think that kids in general cannot gain knowledge on how to play chess really well very fast before they turn 5. Maybe so much early learning and studying chess before the age of 5 for some people can even make it harder for them to learn things later than it would have been if they didn't do all that early learning and studying chess.

---
Tags: learning
---


# Question
Title: Options for following the Norway Chess tournament live
I've heard a new tournament format is being adopted in the new series of Norway Chess, where each drawn classical game is followed by an Armageddon game in order to conclude with a decisive result for each match-up.

What are the recommended (free) websites for following the event live other than the official coverage of the tournament?

# Answer
You can follow the event live from various platforms, to name a few:

**Chess24**: live broadcast of moves and engine analysis available to all users, and the live commentary provided by Jan Gustafsson and Peter Svidler restricted to premium members for this event. But all broadcasts are recorded and available freely on their youtube channel, including Peter Svidler's analysis of a game of the round.

**Lichess**: also provides the live broadcast of moves via its dedicated study page for each round of the tournament. The advantage is more freedom to customize the engine analysis while following a game and also more suitable for following the moves live from your phone.

**Miscellaneous**: There are also various streams providing commentary for the event (see e.g. the twitch page of chess streams), among them is the chessbrah channel having Yasser Seirawan and Nils Grandelius currently as guests.

So there's plenty to choose from given what you're most interested in. If there's one thing I would definitely recommend, is to watch Peter Svidler's post analysis videos of the game of the round as they are highly instructive and fun.
> 2 votes

# Answer
It depends on what you are looking for (comments, video...) but if you are just are looking for the games, chessbomb has them live: https://www.chessbomb.com/arena/2019-altibox-norway-chess
> 0 votes

---
Tags: tournament, norway-chess
---


title: Sicilian Defence, Dragon Variation

text:
# Question
Title: Sicilian Defence, Dragon Variation
```
[FEN ""]
1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be3 Bg7 7. f3 O-O 8. Qd2 Nc6 9. O-O-O d5 10. exd5 Nxd5 11. Nxc6 bxc6 12. Bd4

```

What is White's plan & idea behind 12. Bd4 move?

# Answer
One of the main purposes of playing f3 at the Yugoslavian attack against the dragon is to put pressure on black's king by pushing the kingside pawns (g4, h4-h5).

However the black strong bishop defender should be eliminated in order to put black's king in troubles.

Normally this is done via Bh6.

In this line white is putting pressure on c3 knight, so Bh6 doesn't work.

Bh6?

This is the continuation of Stockfish if Bh6, winning a pawn.

```
[FEN ""]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6
5. Nc3 g6 6. Be3 Bg7 7. f3 O-O 8. Qd2 Nc6
9. O-O-O d5 10. exd5 Nxd5 11. Nxc6 bxc6 12. Bh6 Nxc3
13. Bxg7 Qxd2+ 14. Rxd2 Nxa2+

```

If Nxc3 bxc3 Qa5!, a classical on Dragon, starts a strong attack on queenside (Stockfish gives -8).

```
[FEN ""]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6
5. Nc3 g6 6. Be3 Bg7 7. f3 O-O 8. Qd2 Nc6
9. O-O-O d5 10. exd5 Nxd5 11. Nxc6 bxc6 12. Bh6 Nxc3
13. bxc3 Qa5

```

As said, the idea of this move is not only exchanging bishops but also reducing pressure on the diagonal; Nxc3 is a threat.
> 3 votes

# Answer
Something that instantly stands out to me is that **12. Bd4 challenges black's strong fiancettoed bishop.**

Black must submit to trading pieces or weaken his bishop.

Also,**12. Bd4 removes pressure from the c3 knight.** This piece is in a bit of a weak position, especially since one of its defenders is a pawn next to the king that we don't really want to move, and *definitely* don't want to double up.

Finally, **12. Bd4 could help white control the d-file.** Black's queen could step out of the way much more easily and allow the d1 rook to push the d8 queen off of the open d-file. (For example: Knight takes knight, queen takes knight, bishop takes bishop, rook takes bishop.) The queen is also free-er to move along the "up-and-to-the-right" diagonal.

---

Regarding other future ideas:

A move like **Bc4** might be in order soon: it develops a piece, unites the back-rank rooks, attacks a strong but weakly-defended piece, and has the chance to participate in a kingside attack, eventually. It also protects the hanging a2 pawn.
> 4 votes

# Answer
In the line with 9.0-0-0 d5, by contrast with 9.Bc4 or 9.0-0-0 Bd7, the center gets open and White is more often aiming for play in the center than on the h-file.

White wants to neutralize the strong Bg7 and any possible counterplay on the b-file and exploit the weaknesses on c6, c5, d6 and the open d-file.

After the usual 12...e5 (12...Bxd4 13.Qxd4 Qb6 is more solid but passive) 13.Bc5 Be6!, White does best not to take the offered exchange but to build up her pressure with Ne4, Kb1, Bc4, and often g4-h4 and/or b3-a4.

Black chances are linked with threats against a2 or b2 or activating his pawn majority on the kingside with ...f7-f5.

Fixing the pawn structure, even by closing the kingside (g4-g5 met by ...h6-h5) is good for White because Black would lack levers to create counterplay and White minor pieces all have good active and safe posts near the d-file: c4,c5,e4.

A dream scenario for White:

```
[FEN ""]
1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be3 Bg7 7. f3 O-O 8. Qd2 Nc6 9. O-O-O d5 10. exd5 Nxd5 11. Nxc6 bxc6 12. Bd4 e5 13.Bc5 Be6 14.Ne4 Re8 15.h4 h6 16.g4 a5 17.g5 h5 18.Bc4 Nf4 19.Qc3 Qc7 20.a4

```
> 2 votes

---
Tags: opening, strategy, sicilian-dragon
---


title: Is White controlling this game?

text:
# Question
Title: Is White controlling this game?
Which side is in a better position here : white or black ? Is White controlling this game as all rook, knight, bishop, queen are in open position now ? What are the chances for black to come back ?

```
[fen "rn1qk2r/1p1b1pp1/pPp1p1np/P1PpP1b1/3P4/1Q3N1P/1B1NBPP1/R3R1K1 w Qkq - 0 1"]

```

# Answer
Yes, white is better in this position, because it controls more space. The black position is somewhat cramped, particularly the queenside pieces (Bd7, Nb8, Ra8) are difficult to develop.

The queenside pawns are blocked so the play is going to happen on the kingside. (there might be some tactical ideas for white in the far future related to a piece sacrifice on a6 or c6 creating a strong passed pawn on b6; but for the time being nothing is going to happen on the queenside.)

Typical plans for white in this position:

* quickly move pieces to the kingside before black can develop any counterplay
* potentially exchange the active black pieces (such as Bg5).
* create a pawn break/pawn storm with f4-f5 at some point

Typical plans for black:

* develop queenside pieces
* create some kind of counterplay (perhaps playing f6 at some point later on, without weakening the e6 pawn or kingside pawn structure; having played h6 already is rather bad in this case)

Without giving any concrete lines it seems to me that the white plan is much easier to achieve than black's
> 13 votes

# Answer
> Which side is in a better position here : white or black ?

White is clearly better since he controls more space and is more developed than black.

> Is White controlling this game as all rook, knight, bishop, queen are in open position now?

No, White is not controlling the game. There is still all to play for because the queenside is completely blocked and although White's pieces are all developed, as in "off their starting squares", they are not co-ordinated well and are not on very good squares. White needs to regroup his pieces before he is ready to launch an attack. If he allows the kingside to become as blocked as the queenside then it will be a draw. White should not be in a rush to advance his kingside pawns.

> What are the chances for black to come back?

Black is cramped for space. He needs to either grab more space or exchange off some pieces. However he must be careful not to exchange his best pieces, in particular his dark squared bishop, BxN would be a mistake. He also needs to complete development.

Ideally he would like to castle queenside and then launch a pawn storm against white's castled king, however that would take far too long to engineer, something like Bc8, Nd7-f8, Bd7, Qe7 (NxB from white would help black, allowing QxN), 0-0-0 is 6 moves which black probably doesn't have.

It is important for Black to consider White's plans and how to counter them. White's obvious next move is Bd3 to open the e rook up and to threaten the black knight on g6, thereby discouraging black from moving his f pawn.

Meanwhile either f6 or f5 is key for black to either try and counter the white center or to try and create space on the kingside for his pieces to move and develop, particularly his white-squared bishop which is currently acting like a "tall pawn". Perhaps black should prepare f6 or f5 with moves like 0-0, Be8, Nd7 etc. He must find a way to bring his QR and QN into the game or else he is basically playing a rook and a knight down.
> 8 votes

# Answer
**BLACK IS LOST!**

Plug the position into a chess engine and see the evaluation -- probably thinks White is +5 despite material being equal.

It will be decades before Black can mobilize the queen-side pieces. So in essence play can develop where White will have over-powering force on the king-side.

As White I would start with 1.g3 (which prevents Nf4), followed by Bd3 -- Black's two active pieces are in trouble. Eventually f2-f4, g3-g4, f4-f5 with the board getting squishy from Black's squashed forces; it almost doesn't matter how White pushes on the king-side -- he just moves everything over there.

Black will never break Whites Pawn wall. Even if he gets in f7-f6 the e5 square is firmly under Whites control.
> 6 votes

# Answer
White has a much better position, but all is not lost for black.

```
...   BxN!
NxN   O-O
NB3   PB3

```

White's position still looks better, but black's not too far behind.

```
BQ1   PB4

```

and black has enough time to maneuver his pieces over. Best he can hope for is a draw.
> 1 votes

---
Tags: positional-play
---


title: Longest series of mutual "!" moves

text:
# Question
Title: Longest series of mutual "!" moves
Normally I'd pester the/a computer chess forum, but I couldn't register yet...

On the Matplus chess forum, the following construction task came up.

Both White and Black are on the brink of losing because the position is so sharp. Both players have only one way to draw the game. However, the seqeunce falls under th Nunn convention-each move is the only one that doesn't lose, but it has at least one legal alternative. They are denoted as “!” moves. What is the longest sequence of mutual "!" moves?

Here is an illustrating example:

```
[FEN "2K5/8/7k/6N1/3q1N2/8/8/8 w - - 0 1"]

1. Nf7+ Kh7 2. Ng5+ Kh6 3. Nf7+

```

Nalimov confirms that 1.Sf7+! Kh7 2.Sg5+! Kh6! is the only way to draw (by repetition), but since Kh7 is also an only legal move, this position is invalid.

I don't have Nunns "Secrets" series at hand, where surely some examples can be found. Neither can Imine a database for this question. Maybe you can?

# Answer
> 6 votes
The example below comes from Guy Haworth's *Chess Endgame Records*.

The annotations, as explained by Guy Haworth, are as follows:

% the only move available
! the only value-preserving move available (i.e., for a White move, the only winning move, and, for a Black move, the only drawing move, all others losing)
''' the only move which does not allow a repetition or otherwise waste time
'' the unique optimal move selected by the defined strategy
' an optimal but not unique optimal move

The other notation used is as follows (this is copied from Guy Haworth's book):

Metrics: DTM Depth To Mate

Miscellaneous notation:
AUMS Absolutely Unique Move Sequence

```
[White "KR"]
[Black "KNP"]
[Result "1-0"]
[Date "2013.11.24"]
[Event "5m, 2-3m, KRKNP, GBR 0103.01, longest-known decisive AUMS: SV+M+/SUm"]
[Annotator "Haworth, Guy"]
[FEN "8/8/7p/7n/k7/8/2K5/3R4 w - - 0 1"]

1. Rd4+! {dtc/m/z = -26/-49/-17m} Ka3'' 2. Kd3! Kb3'' 3. Rd6! Kb4'' 4. Kd4! Nf4'' 5. Rb6+! Ka5'' 6. Rf6! Ne2+'' 7. Kc4! Ng3'' 8. Rg6! Ne4'' 9. Kd4! Nd2'' 10. Rg2! Nf3+'' 11. Kc5! Ka6'' 12. Rg6+! Kb7'' 13. Kd5! h5'' 14. Rh6! h4'' 15. Rf6! Ne1'' 16. Rf1! Nc2'' 17. Rb1+! Ka6'' 18. Rb2! Ne1'' 19. Ke4! h3'' 20. Rb1! Nc2' 21. Kd3! Na3'' 22. Ra1! h2' 23. Rxa3+! {KRKP: dtc/m/z = -3/-15/-3m} {Nalimov and Lomonosov DTM EGTs} *

```

Each of the first 35 plies, from White's 1st to White's 18th move, is the unique best for the player. What move is best for Black on their 18th turn depends on the criterion applied. Black's 18th move here, 18 ... Ne1, is the unique move which enables Black to maximise the number of successive White turns at which White has only one winning option. However, if Black is to maximise the number of future turns (i.e. maximise DTM), Ne1 is not best for Black: it loses for Black in 20; best is 18 ... Ne3+ (loses in 32) 19 Kc6 (best; wins in 32; Kc5 wins in 34).

# Answer
> 1 votes
Just to add a note of interest for the people of CSE (excluding Hauke of course who knows of this), here's the current known **record of 32 plies** by Geir Sune Tallaksen Østmoe, borrowed from the question's linked Matplus forums.

The question is asking for the longest, or an example of, series of both sides that are the only drawing move that is dual free in a position without promoted pieces. This is under the "Nunn Convention," which, to my understanding, means that there must be at least one other legal moves, and pawn promotions count as duals.

I do not know of any studies myself, but perhaps I will find something someday. I if I do, I shall update this answer.

Now, here is that 32 ply record, from post number 19.

```
[Title "Geir Sune Tallaksen Østmoe, Matplus.net Forum 8/9/2019, White To Draw"]
[FEN "k1B5/r1p1p2b/nPPP2R1/BN2b1R1/2P2qp1/p7/P3P2P/6Kn w - - 0 1"]

1. Bb7+ Rxb7 2. Rg8+ Bxg8 3. Rxg8+ Nb8 4. Rxb8+ Kxb8 5. bxc7+ Rxc7 6. dxc7+ Bxc7  7. Bxc7+ Qxc7 8. Nxc7 Kxc7 9. Kxh1 Kxc6 10. Kg2 Kc5 11. Kg3 Kxc4 12. Kxg4 Kc3  13. h4 Kb2 14. h5 Kxa2 15. h6 Kb1 16. h7 a2

```

---
Tags: theory, draw, problems
---


# Question
Title: Did Richard Teichmann fail to take his "bishop pair" idea to its logical conclusion?
Playing Black in a game against J.R. Capablanca, Richard Teichmann accepted an isolated queen pawn as the price for getting a bishop pair

On move 20, White played Nf5, attacking his black squared bishop on e7, which was protecting his pinned knight on f5. He accepted the exchange of the knight for his good bishop, then had to sacrifice the h pawn to free his king from the resulting pin.

```
[fen ""]
[Event "Berlin exh"]
[Site "Berlin"]
[Date "1913.11.20"]
[EventDate "?"]
[Round "2"]
[Result "1-0"]
[White "Jose Raul Capablanca"]
[Black "Richard Teichmann"]
[ECO "D63"]
[WhiteElo "?"]
[BlackElo "?"]
[PlyCount "75"]

1.d4 d5 2.Nf3 Nf6 3.c4 e6 4.Bg5 Be7 5.Nc3 Nbd7 6.e3 O-O 7.Rc1
b6 8.cxd5 exd5 9.Bb5 Bb7 10.O-O a6 11.Ba4 Rc8 12.Qe2 c5
13.dxc5 Nxc5 14.Rfd1 Nxa4 15.Nxa4 b5 16.Rxc8 Qxc8 17.Nc3 Qc4
18.Nd4 Qxe2 19.Ncxe2 Rc8 20.Nf5 Kf8 21.Nxe7 Kxe7 22.Nd4 g6
23.f3 h6 24.Bxh6 Nd7 25.h4 Nc5 26.Bf4 Ne6 27.Nxe6 Kxe6 28.Rd2
Rh8 29.Rc2 Rc8 30.Rxc8 Bxc8 31.Kf2 d4 32.exd4 Kd5 33.Ke3 Be6
34.Kd3 Kc6 35.a3 Bc4+ 36.Ke3 Be6 37.Bh6 Kd5 38.Bg7 1-0

```

Teichmann's alternative was to move the bishop back to f8, allowing White to take the knight (and double his pawns on the f file). In that case, he would have two bishops against two knights to compensate for his wrecked pawn structure.

Teichmann was down a clear pawn after the way he played, counting on bishops of opposite color to give him a draw. Would he have been at less of a disadvantage playing the way I outlined in the previous paragraph, given that two knights are worth less than two bishops?

# Answer
> 7 votes
I'm not going to claim in a black-and-white way that your idea of `20...Bf8` is strictly inferior to Teichmann's `20...Kf8` in objective terms, but I can think of two solid reasons not to play into the resulting `20...Bf8 21.Bxf6 gxf6`:

1. Contrary to your general operating premise that two bishops are superior to two knights, in this position White's knights are fantastic, and in particular, Black's poor pawn structure is such that the knights have wonderful outposts to camp in, as well as weak pawns to target down the road. Really, I'd take either of these knights over either bishop in this situation, so much so that if I were playing Black from this point on, I think I'd feel compelled to trade one of the bishops for a knight at some point anyway, and so I'd rather have done so without having compromised my pawn structure in this way.
2. White's position in this line is much *easier to play*. White has no structural weaknesses, while Black has targets in her structure. The knights have natural squares screaming out for occupation, while the light-square bishop is especially hemmed in, not least because of the isolated d5 pawn.

It's tough to give detailed analysis of variations without inline commenting, so I'll just illustrate what I mean with a single line. After, say, `22.g4` to make luft for the king and grab space on the kingside, even a seemingly productive move like `22...Rc2?!` for Black doesn't actually lead anywhere, basically because of the pluses indicated above. For instance, after `23.Ned4` Black can't follow up with `23...Rxb2?`, because after `24.Rc1!` White will gain a big edge while Black looks after her inferior pieces: e.g. `24...a5` (forced, as otherwise the b7 bishop will be embarrassed) `25.Rc7 Ba6 26.Ra7 Bc8 27.Rxa5` and White has a huge plus. Even if it doesn't look that way at first glance, if one plays around with this position a bit, it's much easier to find good moves for White, and it's actually quite difficult to bring the black pieces (including the king) into play without running into trouble.

```
[fen "2r3k1/1b2bppp/p4n2/1p1p1NB1/8/4P3/PP2NPPP/3R2K1 b - - 0 1"]

1...Bf8 2.Bxf6 gxf6 3.g4 Rc2?! 4.Ned4 Rxb2? 5.Rc1! a5 6.Rc7 Ba6 7.Ra7 Bc8 8.Rxa5

```

Again, that's just one illustrative line, and certainly one in which I picked a mistaken idea for Black for effect. But the point is, if Black can't effectively make an active threat like the one indicated without facing such a harsh backlash, then it's not a position in which Black has much of anything to play for, and instead is one through which Black must suffer and just hope to hold on. To me, that's reason enough not to go in for this option over `20...Kf8`.

# Answer
> 3 votes
I would like to point another way for Black to try and hold to the dark squared bishop, without allowing doubled pawns on f6. I believe that 1...Bd8 would be a reasonnable choice in that difficult position, but White still seems winning.

```
[fen "2r3k1/1b2bppp/p4n2/1p1p1NB1/8/4P3/PP2NPPP/3R2K1 b - - 0 1"]

1...Bd8 2.Nd6 Rc7 3.Nb7 Rb7 4.Bf6 Bf6 5.Rd5 Rc7 6.Rd2

```

Capablanca's win against Spielmann in a similar endgame is famous.

---
Tags: analysis, positional-play, minor-pieces
---


# Question
Title: Why is Na5 not played in this line of the French Defense, Advance Variation?
I find Na5 a good resource for black in this line of the french, profiting from the fact that white's b-pawn is binned to the bishop. As far as I can understand this position with my limited chess, I find it a strong move, winning space on queenside with the plan of trying Bd7-Rc8-Nc4 on c-file.

```
[FEN "r1b1kbnr/pp3ppp/1qn1p3/2ppP3/3P4/2P2N2/PP3PPP/RNBQKB1R w KQkq - 3 6"]

6. a3 Nh6 7. b4 cxd4 8. cxd4 Nf5
9. Bb2 Na5

```

However, I don't find this move at the database of chesstempo I use to use for my correspondence games.

Stockfish neither considers it. It even don't play 10....Nbd2 (it plays Nc3) to defend on c4 (which I would expect), and doesn't wonder at all about Nc4 (it simply trades his bishop for the knight; apparently it should result an advantage on the center).

What's my misunderstanding here?

# Answer
> 8 votes
The plan you outlined with ...Bd7, ...Rc8, ...Nc4 is a good strategical plan, but there are a few concrete reasons it doesn't work well:

* In the opening you should be focusing on developing all your pieces and castling. Your plan with maneuvering the knight to c4 will move the same piece three times.
* At depth 33, Stockfish gives 10.Nc3 Bd7 11.Rb1!, breaking the pin on the b2-bishop and attacking the a5-knight. Now you have to move the knight before your a8-rook manages to reach c8. If you go ahead with 11...Nc4 then 12.Bxc4 dxc4 is poor for you. Your new pawn on c4 is mainly a weakness at the moment, and White may blast open the centre with d5 to attack your uncasted king.
* Also, White could always play 10.Qa4+. If you block with 10...Bd7 then 11.Qxa5 wins the knight. So you have to respond with retreating the knight: 10...Nc6.

# Answer
> 8 votes
The Nbd2 --\> Nc4 plan to protect the bishop doesn't work because c4 is attacked by black's pawn. Stockfish takes a more direct route to kick the pin:

```
[fen "r1b1kb1r/pp3ppp/1q2p3/n2pPn2/1P1P4/P4N2/1B3PPP/RN1QKB1R w KQkq - 0 1"]

1. Nc3 {White can kick the pin in a moment.} (1. Nbd2 {This move also poorly develops the knight - and as you can see, c4 is covered anyway.}) 1...Bd7 2. Na4

```

And the pin is already gone. Na5 didn't really do anything in the first place. It was interesting while it lasted, but that wasn't long. It wasn't exactly a *bad* move, even (lichess would call it an "inaccuracy," I'd wager); however, there are better ideas here, such as the simple developing move Bd7.

---
Tags: positional-play, french-defense
---


title: Ruy Lopez, Exchange Variation

text:
# Question
Title: Ruy Lopez, Exchange Variation
```
[FEN ""]
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 dxc6 5. Nc3 f6

```

Theory recommends 5. ... f6. Why? What is the specific reason behind this move? How this move helps Black? Other than 5. ... f6, are there any other good moves available for Black?

# Answer
Not only does 5...f6 protect the e5-pawn, but it also resists against White pushing his own pawn to e5 (if Black's e5-pawn gets exchanged off).

Consider the main line of 5...Bd6: 6.d4 exd4 7.Qxd4. Now White's threatening e5, along with Qxg7. Black's only move to maintain the balance is thus 7...f6. So he ends up having to play the move anyway, but perhaps under less favourable circumstances.

Comparatively: 5...f6 6.d4 exd4 7.Qxd4 Qxd4 8.Nxd4 sees Black exchanging off the queens, making it much safer for his king (which is still a fair number of moves away from castling).

All this being said, 5...Bd6 is completely playable, along with 5...Bc5 and 5...Bg4. But 5...f6 is simply the most solid and safest way to reinforce the e5-pawn.

Funny side note, on live book someone let Stockfish somehow think to depth 53, and it gives 5...f6 as the best move with an evaluation of -0.18.
> 3 votes

# Answer
White is threatening to take the pawn on e5. It couldn't take it with 5.Nxe5 because, since the pawn on d4 is undefended, Black can immediately get it back with ...Qd4 6.Nf3 Qxe4+. Or Black could also consider ...Qg5 followed by ...Qxg2. With 5.Nc3, the e4 pawn is defended, making the threat of taking on e5 more serious. If you look at games between highly rated players, 5...f6 is indeed the most popular move, but there are other alternatives that are also fairly frequent, such as ...Qd6 and ...Bd6. I'm pasting below the table from the lichess opening book. If you look at all the popular moves (say those with more than 10 games), they all defend the pawn one way or another (in the case of 5...Bc5 it is a bit tactical).

That said, I don't know why defending with ...f6 is the most popular. It is simple and solid, I suppose (maybe they prefer to defend a pawn with a pawn to give more freedom to the pieces?). If you go by results, protecting the pawn with the queen or bishop (the second and third choices above) are also fairly common moves and actually have a higher frequency of wins for Black (but also for White!).
> 4 votes

# Answer
I think it has more to do with the surviving bishop for white. Since it covers black squares then this move indeed closes the board for that bishop.
> 1 votes

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