Looking for a single, good opening that revolves around a “crab” pawn structure I have often heard (or this one video just got it stuck in my head) Youtube videos (the timestamp is 2:37, nothing else relevant) refer to this kind of pawn structure as a “crab” pawn structure (below, white pawns.) The name makes sense because it is like a crab pincer enclosing the board, as agadmator said.
This is just an example; it is not to be analyzed.
[FEN ""]
[startply "8"]

1. e3 f5 2. f4 Nf6 3. c4 c5 4. d3 Nc6

Is there a good opening that revolves around such a “crab” pawn structure? I seek merely one, not all possible ones. As long as the structure of the pawns, as shown in the example, is the same, the “crab” can be anywhere on the board.
I would like to utilize such an unorthodox playing method to surprise opponents. I would like to know the advantages/disadvantages of the opening, such as how to counter/play it. There is no need to cover all possible variations.

To answer your question, there are no good openings that revolve around this "crab" pawn structure. This is because this structure takes a lot of pawn moves, decreases the mobility of your bishops, and creates weakness on the kingside. It would even be difficult to come up with a respectable variation of any opening that has this pawn structure (perhaps the variation in the link provided is playable, but I don't think it gives an objective advantage).
Of course the pawn structure in the link is different than the one you displayed. Either way, I recommend avoiding these "crab" structures at all costs.
If you want to surprise you're opponent with unorthodox openings in an aggressive manner, try some gambits out. For example, King's Gambit, Smith Morra Gambit, Evans Gambit, etc.


Is Rover opening sound in crazyhouse opening theory? The rover opening 1. a4 is played a lot on the lichess server and there have been some high level games in it. The opening is not gaining any initiative or tempo, it is just rook lifting prematurely, which is a terrible idea in normal chess, but works a bit in crazyhouse.
Does anyone have a lichess study or a good explanation on how to get good lines out of the Rover opening.

I don't think it's a good idea to rook lift this early in crazy house. Lichess's carzy house computer actually says that 1.e4 gives white a +2.3 advantage and 1.a4 gives white -1.0. In crazy house, you have to get your pieces out as fast as possible.


Pawn storm, should I start with h4 or g4? If Black has castled kingside and White castled queenside or kingside, and White wants to launch an attack by a pawn storm. How do you know that you should start with h4 first or g4 first? I know that it depends on the pawn structure of Black.

1) Black can have a kings-indian or dragon sicilian setup around the king (Bishop on g7, knight on f6, and pawns on f7 g6 h7). In these examples, how should white start the pawn storm

[fen "rnbq1r2/pp2ppbk/2pp1npp/8/2PPP3/2N1BP2/PP1Q2PP/R3KBNR w KQ - 2 9"]

[fen "r1bqr1k1/pp2ppbp/2np1np1/8/3NP3/2N1BP2/PPPQ2PP/2KR1B1R w - - 6 10"]

[fen "r1bq1rk1/p4p1p/2p1p1p1/3n4/3Q4/2N2P2/PPP3PP/2KR1B1R w - - 0 14"]

2) A QGD pawn setup (knight on f6, pawns on f7 g7 h7).

In this example where black committed g6, how should white start the pawn storm?

[fen "r3r1k1/pp2bp1p/4pnpB/q3N3/2Pp1Q2/8/PP3PPP/3RR1K1 w - - 4 20"]

If Black plays pawn to h6 to defend, then with which pawn should White start the attack? g4 or h4? And if Black doesn't move the pawns (pawns on f7 g7 h7), then how should white start the pawn storm?

Typically you use a pawn storm to exchange pawns around the castled enemy king and thereby to open lines and diagonals for an attack. Most of the time you want a closed (to some extent) center in order to avoid counterplay in the center.

In this sense your example 4 is not a typical use case for a pawn storm. It might make sense to push the pawns here as well, but the reason for that are concrete tactical motifs. E.g. by playing g4-g5 you seem to force black to exchange the bishop for the knight after which there are ideas with Qg7 mate...

Other than that, it depends a lot on the actual position.

A typical defensive strategy is to block the advancing pawns, thereby halting the pawn storm. In your first example you need to consider that if you play g5 black can block with h5, if you play h5, black can block with g5. To break such blockades, you could consider piece sacrifices (for a pawn or two) or what options you have by pushing the f pawn.

In your second example, if you play g5, black can block with Nh5. In your third example, playing first g4 leaves you with lots of weak dark squares that are eyed by the black queen and knight. Playing first h4 here seems like a much better choice (if you had to decide between g4 or h4).

Some general guidelines (but as mentioned above, don't follow these blindly) depending on the opponent's pawn structure (of course the same applies to exchanged colors):

Pawns on f7-g7-h7

typically broken by playing g6 supported by a pawn from h5. See English attack in the Najdorf Sicilian.
You could also attack with h6, but this really only makes sense if you can make use of the dark squares, e.g. if you have a queen, dark squared bishop... that can enter via the a1-h8 diagonal or if you have a knight that could use the outpost that forms on f6.

Pawns on f7-g6-h7

Break with h5. Most of the time you want rooks on the h-file for the attack, when the h-file opens. See Yugoslav attack in the Sicilian Dragon.
Need to consider whether black can close the position with g5 after you play h5. Therefore in some cases, white wants to play g5 before h5.

Pawns on f7-g6-h6

This is a flexible setup for black, because whether you play h5 or g5, black can always block replying g5 or h5 respectively.
One idea to break it is with a pawn on f4, so as white you aim for h5 but have a pawn on f4 (ready or can play later) in order to prevent the blocking with g5.
Another idea to break it is tactically. Often you end up with such positions, like in your first example, with Qd2, Be3 and Kh7. A typical tactical idea then is to play Ng5 with a white pawn on h4 and a rook on h1. If black takes the pawn hxg5, white opens the h-file with hxg5 check which very often is deadly.

Pawns on f6-g7-h7

You'd go for the f6 pawn by playing g5. Need to consider, whehter black can reply with f5 after which there is not much of an attack.
Sometimes you could follow up with h5-h6 with the idea that the g7 pawn moves and cannot recapture on f6.
See attacks against the Sämisch in the Kings Indian. (i.e. pawn storm by black)

As mentioned these don't work all the time and depend on the concrete position. If you consider the potential for blocking the pawn advance, by closing the structure, which pawn to push often comes naturally.

I'd recommend to look at some of these attacks in actual games. You can use the openings mentioned above as a guideline.


Did black misplay here or did I miss something? I'm getting back into chess after a hiatus of 8+ years, so I'm a bit rusty. This position is from a game I just played online.

I'm white and it's my move. I threaten black's rook and knight with Qd5, and this is how it played out. I'm amazed it worked in my favor, because as far as I can tell, instead of 3. - a6, he could have moved 3. - Qf6, which would save him after a few exchanges. Am I missing something, or did he just make the wrong move?

EDIT: Removed irrelevant sentence about Kf7.

r1b1kbnr/p1pp4/1p6/4nP1p/6pq/2N5/PPP1BPPP/R1BQ1RK1 w - - 0 1

1. Qd5 Nc6
2. Bb5 Nge7
3. Re1 a6
4. Bxc6 dxc6
5. Qxc6+ Bd7
6. Qxa8+ Kf7
7. Qxa6

As you saw in your game a6 failed terribly as it's simply inviting white to take on c6 and win the rook. Black had a better way of avoiding all of this a move earlier, i.e. 2. Bb5 Nf6 instead of Nge7. See illustration:

r1b1kbnr/p1pp4/1p6/4nP1p/6pq/2N5/PPP1BPPP/R1BQ1RK1 w - - 0 1

1. Qd5 Nc6
2. Bb5 Nf6
3. Re1+ Kd8
4. Qd2 (4. Qd3 Bc5) (4. Qc4 Bc5)

Finally as for Qf6, as has been suggested in comments by others, it simply loses to Ne4 (or the engine move which is Bf4, but it doesn't matter as Ne4 is good enough):

r1b1kbnr/p1pp4/1p6/4nP1p/6pq/2N5/PPP1BPPP/R1BQ1RK1 w - - 0 1

1. Qd5 Nc6
2. Bb5 Nge7
3. Re1 Qf6
4. Ne4 Qf7
5. Bxc6 dxc6
6. Qe5 Bg7
7. f6

So both a6 and Qf6 blunder the game away, the former bit more horribly so.


Does this process ever becomes a second nature? I have started playing "real chess" but the problem is it takes too much time. How will I able to win in small time-controls? Does this process of searching the opponents threats and looking for candidate moves ever become a second-nature?

If you are interested in the psychology of learning and improving in chess, I really recommend reading Chess for Zebras from Jonathan Rowson (and/or Move First Think Later from Willy Hendriks, which has a very similar message).
tl;dr: Yes, finding the "best" move continually becomes more and more natural (and thus faster!) while you improve (although even masters never reach the point of perfection).
Rowson explicitly distinguishes between Knowledge (theory learned from books etc.) and Skill (the practiced ability to actually use that knowledge on the board). If you think about learning languages, the former would be knowledge about grammar and vocabulary (you can learn that to a reasonable degree in school), and the latter would be the ability to speak/write fluently (you can only really learn this by constant practice of the language). Someone with only school knowledge will have to consciously think about everything and thus needs more time than a skilled speaker to form sentences - even if he/she knows all the parts!
It works roughly the same way in chess, up to the point that strong masters can often subconsciously "feel" a move within seconds and then "just" have to use their calculation abilities to make sure it actually works.


Is this case considered an ambiguity or not? From the answer to my question How are PGN ambiguities handled?:

  In the case of ambiguities (multiple pieces of the same type moving to
  the same square), the first appropriate disambiguating step of the
  three following steps is taken: ...

After reading that, a new ambiguity surged from that disambiguation, it is not clear what would happen if the pieces that look like they can move to a same square are all pinned except one piece, is then a need to disambiguate even if only one of those pieces can legally move in there?

Here is an illustrated example:

[FEN "4k3/8/8/8/8/8/8/q2NKN2 w - - 0 1"]

Should I use Ne3 or Nfe3?

While it's not ambiguous (only Nfe3 is legal), it is better to be specific with Nfe3.  Successful software can deal with both Ne3 and Nfe3, but not every pgn parser is perfect, and some beginners will appreciate the additional guidance.


Rook and Pawn Endgames I want to learn more about rook and pawn endgames because they are very common. But it’s such a broad subject - where should I even begin?

For example, I do know of the Philidor and Lucena positions, but are there any other fundamental endgames positions I should know? Or should I take a different approach to getting started here?

Thanks so much!

Before consulting a book, try reading the Wikipedia article on rook and pawn endgames.

As you mention, it's a very broad topic.


Is there a list of approximate ELO ratings for each Stockfish level? I want to create something that will select an appropriate Stockfish difficulty setting automatically given the player's rating. The straight Stockfish v11 that I've downloaded has 20 difficulty settings, and various other settings for controlling thinking time. Is there a resource that has approximate ratings for the levels? If that doesn't exist, what method would be recommended for finding the approximate ratings of chess engines when I'm starting from scratch?
EDIT: Sopel gave a link some time ago, that answers the problem, although they did it in comment form so I can't mark it as the correct answer

They have a development pipeline doing testing based on one of the early versions.
I saw a graph of such test in some heavy loading page from Next Chess Move website:

Stockfish Development Builds

The development page gathering the test linked from the Fishtest wiki:

Stockfish Testing Queue

And for completion:

Fishtest GitHub Repository Wiki


How can I automatically extract features from a position? I am working on a project where I take a chess board position (FEN string converted to binary) & it's evaluation score and feed it to a neural network. My aim is to make the neural network differentiate between good and bad positions.

How I encode the position : There are 12 unique pieces in chess i.e pawn, rook, knight, bishop, queen and king for white as well as black. I encode each piece using 4 bits with 0000 denoting an empty square. So the 64 squares are encoded into 256 bits and I use 6 more bits to denote game state like whose turn it is to move, king-castle status, etc.

Problem : Since the input space for chess positions is neither smooth nor uni-modal (one small change in the board position can result in a huge change in the evaluation score), the neural network doesn't learn well. Now, the next logical thing to somehow extract useful features (like material difference, center control, etc) and feed it to the network.

I do not want to hand pick the features as I want the network to learn everything by itself. Therefore I am thinking of extracting features automatically using autoencoders. Is there any better way to accomplish this?

Summary : What is the best way to automatically extract features from a chess board position so that it can be fed into a neural network?

UPDATE : To generate training data, I have modified Stockfish to dump it's evaluation process into a log file. So every new move(position) it considers is written to a file as an FEN string along with it's eval score

I do not want to hand pick the features as I want the network to learn everything by itself.

There is an AI-Koan concerning this situation:

  In the days when Sussman was a novice, Minsky once came to him as he
  sat hacking at the PDP-6.

  "What are you doing?", asked Minsky.

  "I am training a randomly wired neural net to play Tic-Tac-Toe" Sussman
  replied.

  "Why is the net wired randomly?", asked Minsky.

  "I do not  want it to have any preconceptions of how to play", Sussman said.

  Minsky then shut his eyes.

  "Why do you close your eyes?", Sussman asked his teacher.

  "So that the room will be empty."

  At that moment, Sussman was enlightened.

Think about it.


What is a fortress in chess? Throughout the 2016 World Championship match, analysts have made many references to the term "fortress". What does it mean, and how can I use it to my advantage?

A fortress in chess is a position in where the weaker side defends by making waiting moves, and where the stronger side cannot make any progress as long as the defender does not make a crazy move. A very well-known fortress position is the following:

[fen "6k1/6p1/5r1p/8/Q7/8/7P/6K1 w - - 0 1"]

It is impossible for white to make any progress if black just moves his king around in the corner, since the black rook denies the white king any possibility to infiltrate as long as it stands on f6. Since the rook is guarded by the g7 pawn, and the g7 pawn is in turn guarded by the black king, the only way to make progress would be to force the black king out of the corner. However, this is not possible.

The way you use it to your advantage in your own games is as always: understand the concept, and recognize when a fortress is possible in your own games.


Human analysis for a KRBNNPP against KRRN ending? This line of play leads to this position:

[White "White"]
[Black "Black to move"]
[FEN "8/rp4p1/1N1nkb2/3n4/6R1/1R6/8/2K5 b - - 1 38"]

StockFish 10+ assures me that Black has a big advantage, but I am interested to know whether it is possible to humanly analyze it and be completely certain of a winning strategy. Although SF suggests keeping my pieces, my instinct is to exchange as many pieces as possible except the pawns, while pushing the pawns to queen, which includes taking the knight immediately. However, is there any hope of proving a winning strategy here, rather than relying on intuition? I think this is somewhat plausible because Black has enough minor pieces for the king to hide behind (even after exchanging 2 of them), and so White cannot make sustained checks. The question is whether there is a systematic way for Black to push the pawns that is guaranteed to work.

I do not see any convincing reason that there cannot be a proof of a winning strategy, because there are numerous examples of endgames with human analysis of the optimal strategy (e.g. a,b,c,d,e). If the position was not so imbalanced, I know it would be much harder to prove a win. But here, Black has sufficiently many pieces that I feel there should be a proof that we can force some trades to get to a certain winning position. That is also why I would choose to take the knight immediately to hopefully make a full analysis humanly tractable.

@SmallChess is right. This position is absolutely hopeless for White, and there is a very human strategy for Black, which consists here in not exchanging pieces, but hunting the white king. This strategy will force White to exchange pieces unfavorably or White will lose material to avoid being mate.

The principle behind this strategy is simple "with three or more pieces in the attack the enemy king will not be able to escape."

Here is an example where nothing is forced but it's very difficult to suggest good ideas for White. White is completely squeezed.

[White "White"]
[Black "Black to move"]
[FEN "8/rp4p1/1N1nkb2/3n4/6R1/1R6/8/2K5 b - - 1 38"]

1...Nc3! {Black chases the king and cuts off the two rooks. They can't easily coordinate.} 2.Nc4 Nde4! {same strategy: coordinating the pieces to go against the White king} 3.Kc2 (3.Ra3 {is probably better but now Black is happy to exchange and push the g pawn} 3...Rxa3 4. Nxa3 Kf5 5.Rg2 g5-+) b5 4.Ne3 (4.Rxb5 Nxb5 5.Rxe4 Kf5-+ {does not help White}) Rc7 {here with get our principle of three or more pieces in the attack and the White king feels unsafe} 5.Rg2 (5.Kd3 Nf2-+) Na2! 6.Kb1? (6. Kd1 {is better but the King does not escape} Rc1+ 7. Ke2 Nac3+ 8. Kf3 Rh1-+) Rc1 7.Kxa2 Ra1#


What material handicap would be required to compensate for a single double-move? Consider the following chess variant:

Black can, once per game, make two moves in a row (the second move may not capture the King)
To compensate for this advantage, Black gets a material handicap
Otherwise, the standard rules of chess apply

The question is, approximately what material handicap would be needed for the game to become roughly balanced? It is clear that making two consecutive moves, even only once per game, is a tremendous advantage. My guess is that at least a Queen handicap is necessary, since it is trivially easy to capture White's Queen with two consecutive moves once the pieces are out.

Has this chess variant been studied before?

The question can never be answered in a general fashion. Every move has its own perks and advantages. The major variables are these:

Is the same piece allowed to move twice or can black move two pieces once?

Are captures allowed? With just one move of the king's pawn already made, it is possible for any party to capture the opponent's queen within two moves. (Or put them in a position where it cannot escape capture in the next few moves). Here the price for two moves is AT LEAST a queen (since the two moves party would not only have captured the queen, but also invaded inside the enemy ranks).

Starting from midgame, two moves can easily put the opponent in a mate-in-x position where they cannot avoid mate. For example, if one has several mating combinations available, there can be no possible compensation to that!

All in all, I think the option of two moves can/should be made available only in the opening and the price is the queen. It is disastrous and potentially game-losing to allow the opponent double moves in the middlegame or endgame and there can be no compensation to that.


Does the chick promotion rule in dobutsu shogi really matter? In dobutsu shogi, the chick (Japanese pawn) promotes to a chicken (Gold general). In my experience this promotion occurs only rarely and I suspect after much blundering.

Does the chick promotion rule in dobutsu shogi really matter? That is, does the game really change if chick promotion is dropped (and chicks become stuck on the last row instead)?

By really change, I mean the classification of a position (winning, losing or drawing) changing, or the precise sequence of moves to force a win from a winning position changing materially.

The promotion rule actually matters a lot. With perfect play the game ends in a draw instead of a win for white/gote if you drop the promotion rule. In fact, the evaluation of all four moves in the initial position changes in this way.

I have used two independent methods to get this result in order to double-check that there is no bug in my implementations:

Using an engine with alpha-beta search, namely my Stockfish fork for fairy chess variants (including shogi variants), I ran deep searches (~1h) before and after disabling the promotion rule, see the results below.
Since dobutsu shogi is a solved game, there are tablebase generators for it. I have used an open-source tablebase generator and modified it to disable promotions (I am not very familiar with this code base, but since the results of the two methods are consistent, my change seems to work fine). I ran the tablebase generation with both rule sets and checked the results, which you can find below.

1. Search results

input:

setoption name multipv value 4
setoption name hash value 4096
setoption name UCI_Variant value dobutsu
position startpos
go depth 90

output with promotion rule:

info depth 90 seldepth 87 multipv 1 score mate -43 nodes 2423491649 nps 889420 hashfull 338 tbhits 0 time 2724798 pv c1c2 a4a3 c2c1 b3b2 a1b2 c4b3 C@a1 C@a2 c1c2 a2a1+ b2a1 b3c2 b1c2 a3b3 c2b1 b4a3 E@b2 a3b4 b2c1 b3a3 a1b2 a3a4 b1c2 b4c4 b2c3 a4a3 c3b2 a3a2 C@a1 a2b2 c2b2 G@b3 b2b1 E@a3 G@c2 C@c3 c2b2 c4b4 b2a2 b4a4 a2a3 a4a3 a1a2 a3b4 b1a1 G@c2 a1b1 b4c4 E@a1 b3b4 a1b2 c4b3 a2a3 b4c4 b1a1 c2c1 b2c1 b3a3 G@a2 a3b3 a2b2 b3a4 b2a2 C@a3 c1b2 a3a2 a1a2 c3c2 C@b3 E@c3 b2c3 c4c3 b3b4+ a4b4 E@b2 c3b3 a2b1 b3b2 b1b2 E@a3 b2a1 E@b2 a1b1 G@a1 b1c2 C@c3
info depth 90 seldepth 87 multipv 2 score mate -43 nodes 2423491649 nps 889420 hashfull 338 tbhits 0 time 2724798 pv b1c2 b3b2 a1b2 c4b3 c2b1 a4a3 C@a1 C@a2 c1c2 a2a1+ b2a1 b3c2 b1c2 a3b3 c2b1 b4a3 E@b2 a3b4 b2c1 b3a3 a1b2 a3a4 b1c2 b4c4 b2c3 a4a3 c3b2 a3a2 C@a1 a2b2 c2b2 G@b3 b2b1 E@a3 G@c2 C@c3 c2b2 c4b4 b2a2 b4a4 a2a3 a4a3 a1a2 a3b4 b1a1 G@c2 a1b1 b4c4 E@a1 b3b4 a1b2 c4b3 a2a3 b4c4 b1a1 c2c1 b2c1 b3a3 G@a2 a3b3 a2b2 b3a4 b2a2 C@a3 c1b2 a3a2 a1a2 c3c2 C@b3 E@c3 b2c3 c4c3 b3b4+ a4b4 E@b2 c3b3 a2b1 b3b2 b1b2 E@a3 b2a1 E@b2 a1b1 G@a1 b1c2 C@c3
info depth 90 seldepth 87 multipv 3 score mate -43 nodes 2423491649 nps 889420 hashfull 338 tbhits 0 time 2724798 pv b1a2 a4a3 a2b1 b3b2 a1b2 c4b3 C@a1 C@a2 c1c2 a2a1+ b2a1 b3c2 b1c2 a3b3 c2b1 b4a3 E@b2 a3b4 b2c1 b3a3 a1b2 a3a4 b1c2 b4c4 b2c3 a4a3 c3b2 a3a2 C@a1 a2b2 c2b2 G@b3 b2b1 E@a3 G@c2 C@c3 c2b2 c4b4 b2a2 b4a4 a2a3 a4a3 a1a2 a3b4 b1a1 G@c2 a1b1 b4c4 E@a1 b3b4 a1b2 c4b3 a2a3 b4c4 b1a1 c2c1 b2c1 b3a3 G@a2 a3b3 a2b2 b3a4 b2a2 C@a3 c1b2 a3a2 a1a2 c3c2 C@b3 E@c3 b2c3 c4c3 b3b4+ a4b4 E@b2 c3b3 a2b1 b3b2 b1b2 E@a3 b2a1 E@b2 a1b1 G@a1 b1c2 C@c3
info depth 90 seldepth 85 multipv 4 score mate -42 nodes 2423491649 nps 889420 hashfull 338 tbhits 0 time 2724798 pv b2b3 c4b3 a1b2 a4a3 C@a1 C@a2 c1c2 a2a1+ b2a1 b3c2 b1c2 a3b3 c2b1 b4a3 E@b2 a3b4 b2c1 b3a3 a1b2 a3a4 b1c2 b4c4 b2c3 a4a3 c3b2 a3a2 C@a1 a2b2 c2b2 G@b3 b2b1 E@a3 G@c2 C@c3 c2b2 c4b4 b2a2 b4a4 a2a3 a4a3 a1a2 a3b4 b1a1 G@c2 a1b1 b4c4 E@a1 b3b4 a1b2 c4b3 a2a3 b4c4 b1a1 c2c1 b2c1 b3a3 G@a2 a3b3 a2b2 b3a4 b2a2 C@a3 c1b2 a3a2 a1a2 c3c2 C@b3 E@c3 b2c3 c4c3 b3b4+ a4b4 E@b2 c3b3 a2b1 b3b2 b1b2 E@a3 b2a1 E@b2 a1b1 G@a1 b1c2 C@c3

output without promotion rule:

info depth 90 seldepth 52 multipv 1 score cp 0 nodes 2745548262 nps 965315 hashfull 244 tbhits 0 time 2844199 pv b1a2 a4a3 a2b1 b3b2 a1b2 c4b3 C@a1 b4a4 c1c2 b3c2 b1c2 G@b3 b2c3 C@c4 c3b2 a4b4 E@a2 c4c3 c2c1 b3b2 c1b2 E@b3 b2b1 b3a4 G@b2 b4c4 b1c1 a4b3 a2b3 a3b3 b2b3 c4b3 G@b2 b3c4 E@b3 c4b4 c1b1 G@a3 b3a2 b4c4 b1c1 E@a4 c1b1 a4b3 b2b3 a3b3 a2b3 c4b3 G@b2 b3b4 E@b3
info depth 90 seldepth 52 multipv 2 score cp 0 nodes 2745548262 nps 965315 hashfull 244 tbhits 0 time 2844199 pv b1c2 b3b2 a1b2 c4b3 c2b1 a4a3 C@a1 b4a4 c1c2 b3c2 b1c2 G@b3 b2c3 C@c4 c3b2 a4b4 E@a2 c4c3 c2c1 b3b2 c1b2 E@b3 b2b1 b3a4 G@b2 b4c4 b1c1 a4b3 a2b3 a3b3 b2b3 c4b3 G@b2 b3c4 E@b3 c4b4 c1b1 G@a3 b3a2 b4c4 b1c1 E@a4 c1b1 a4b3 b2b3 a3b3 a2b3 c4b3 G@b2 b3b4 E@b3
info depth 90 seldepth 50 multipv 3 score cp 0 nodes 2745548262 nps 965315 hashfull 244 tbhits 0 time 2844199 pv b2b3 c4b3 a1b2 a4a3 C@a1 b4a4 c1c2 b3c2 b1c2 G@b3 b2c3 C@c4 c3b2 a4b4 E@a2 c4c3 c2c1 b3b2 c1b2 E@b3 b2b1 b3a4 G@b2 b4c4 b1c1 a4b3 a2b3 a3b3 b2b3 c4b3 G@b2 b3c4 E@b3 c4b4 c1b1 G@a3 b3a2 b4c4 b1c1 E@a4 c1b1 a4b3 b2b3 a3b3 a2b3 c4b3 G@b2 b3b4 E@b3
info depth 90 seldepth 59 multipv 4 score cp 0 nodes 2745548262 nps 965315 hashfull 244 tbhits 0 time 2844199 pv c1c2 a4a3 c2c1 b3b2 a1b2 c4b3 C@a1 b4a4 c1c2 b3c2 b1c2 G@b3 b2c3 C@c4 c3b2 a4b4 E@a2 c4c3 c2c1 b3b2 c1b2 E@b3 b2b1 b3a4 G@b2 b4c4 b1c1 a4b3 a2b3 a3b3 b2b3 c4b3 G@b2 b3c4 E@b3 c4b4 c1b1 G@a3 b3a2 b4c4 b1c1 E@a4 c1b1 a4b3 b2b3 a3b3 a2b3 c4b3 G@b2 b3a4 E@b3 a4b4 b1c1 G@a3 b3a2 b4c4 c1b1 E@b3

See the UCI protocol description for details on the meaning of the in- and output.

2. Tablebase results

input:

show lines

output with promotion rule:

Gc4-c3 : #-78  (25.00%)
Lb4-c3 : #-78  (25.00%)
Lb4-a3 : #-78  (25.00%)
Cb3xb2 : #-76  (24.99%)

output without promotion rule:

Cb3xb2 : 0     (25.00%)
Gc4-c3 : 0     (25.00%)
Lb4-c3 : 0     (25.00%)
Lb4-a3 : 0     (25.00%)

Please note:

The mate distances differ for two reasons:

Stockfish counts the mate distance in full moves (unless you enable the USI protocol), whereas the tablebase generator counts in ply (half moves).
The search does not not necessarily find the shortest way to mate, whereas the tablebase result should be accurate.

The two softwares also use different coordinate systems to describe the squares (the ordering of ranks is inverted), so be careful not to mix them up when comparing move strings.


Threefold repetition in view of castling rights In view of castling rights, an aspiring rules lawyer could ask: when does threefold repetition support a draw claim? Technical example:

[fen ""]
[title "Illustration of castling rights"]
[startply "13"]
[startflipped "0"]

1. e4 g6 2. b3 Bg7 3. g3 BxRa1 4. e5 b6 5. Na3 Bb7 6. Qg4 BxRh1 7. Nc4 Nc6 8. Kd1 Nb8 9. Ke1 Nc6 10. Kd1 Nb8 11. Ke1

The aspiring rules lawyer's question is not actually my question today. My questions today rather are these:

Has an arbiter ever expressed an opinion, given advice or issued a ruling regarding threefold repetition in view of castling rights?
Have competent persons in any chess federation ever discussed the matter?
Do parallel or otherwise related laws, opinions, advice, rulings or discussions by arbiters, federations or competent persons exist that indicate the principles by which such a case might be judged?

The three questions are related and answers to any or all of the three—or even partial answers to any of the three—would be read with interest. I seek insight into how chess authorities have approached (or would approach) such problems.

Related question here. Related answer here. FIDE's laws of chess here.

UPDATE

The excellent, concise, informative, well-researched answers of @BrianTowers and @TonyK, taken together, perfectly illustrate the reason the question has been asked. Both answers are recommended and, naturally, both have been upvoted by me. Ironically however, under the circumstance, neither answer can be accepted over the other, can it, for only the two answers together serve to illustrate the point.

Since the two answers so perfectly capture the two sides, my preference would be that further answers (if any) avoid taking sides but rather focus on the three items listed above.

ILLUSTRATION BY @REMELLION

Incidentally, before the question was asked, @Remillion had composed a problem position to illustrate a related point. He had originally meant the position as a joke but, since he has mentioned the position in comments in the present context, we can diagram it here.

[fen "B6N/1p1pp3/4pp1P/7P/7P/2p4P/1PPP2rr/R3K2k b - - 0 1"]
[title "By @Remellion: black to move; helpmate in 2"]

This is dealt with explicitly in article 9.2.2 -

  9.2.2 Positions are considered the same if and only if the same player has the move, pieces of the same kind and colour occupy the same
  squares and the possible moves of all the pieces of both players are
  the same. Thus positions are not the same if:
  9.2.2.1 at the start of the sequence a pawn could have been captured en passant
  9.2.2.2 a king had castling rights with a rook that has not been moved, but forfeited these after moving. The castling rights are lost
  only after the king or rook is moved.

Neither of white's rooks move hence castling rights are not affected until the king moves.

In general provided white has not moved his king he may castle on the side on which a rook which has not moved has been captured. I believe there are even puzzles which rely on this for the solution.


Do chess clocks typically provide count up features? I've decided to purchase a chess clock for productivity at work, and I really like the dual display of the chess clock: one timer for work, another timer for fooling around. However, I'd like to know, do game clocks typically offer count-up mode rather than count down?

It is not a typical use case, so you will definitely want to make sure that the clock you're purchasing does have a count-up mode (or is analog, in which case, you probably want to make sure it is quiet). The Chronos digital clock does have a couple of count-up modes (UP-1 and UP-2).


lichess puzzle 61124 I am a beginning chess player, and just had a look at lichess puzzle 61124. The following contains spoilers.
The solution to the puzzle is supposedly Rd4, then the follow-up move from white is Nb6, which I do not follow. Would Qb5 not make more sense from white's perspective?

After Qb3 or Qb5, black has the move Rb4 - kicking the queen away from the defense of the knight. In that line, white is losing a full piece. There is slightly more compensation by instead playing Nxb6 Rxc4 Nxc4 because at least there the black king is also exposed.
If you're ever confused on why the engine played the move it did, just turn on the analysis afterwards. Make the move that you expected the engine to play and see why that loses worse than what was actually played - that way you can learn without having to ask an online forum for help :P


What is the etiquette (or tournament rule) for the act of capturing a piece? There are a few different possible ways of capturing an opponent's piece. You could:

Pick up both your piece and their piece simultaneously with both hands, then set your piece down where their piece was.
Pick up both your piece and their piece using the same hand, and then set yours down.
Remove their piece from the board first, and then use the same hand to move your piece.
Pick up your piece, use it to shove theirs out of the way, set down your piece, and then remove their piece.

And perhaps there are a few other ways as well.

Which of these ways are the best etiquette? (The "shove theirs out of the way" method seems particularly inappropriate.) Are any of these ways illegal under tournament rules? (Don't the USCF rules say that a move must be made with one hand?)

Seeing how Super Grandmasters capture pieces can be instructive:
Garry Kasparov
Capturing an adjacent piece:

Capturing a distant piece:

Source: YouTube
Carlsen (white) vs Caruana

Source: YouTube
Aronian (white) vs Morozevich

Source: YouTube
Hikaru Nakamura (white) vs Vladimir Kramnik

Source: YouTube
Summary:
With the exception of Kramnik, captures proceed as follows:

Lift the opponent's piece and palm it.
With the same hand, move your piece.
Stop the clock using the hand holding the captured piece.
Table the piece.

It's worth noting that it's OK to table the piece in your opponent's time; you do not have to table it before you stop the clock.
Kramnik (playing black in the final image) lifts his own piece before transposing it with Nakamura's pawn in one quick snap. Kasparov also does this with the pawn capture in the first gif. This isn't wrong, it's just a different – and perhaps more aggressive – style. It does not matter if you lift your piece or your opponent's piece first, but all high-level players touch both pieces and the clock with the same hand. (Note that Magnus as white tables the piece on his right even though the clock is on his left.)
It's probably safer not to use two hands for captures or castling, as tournament rules vary on the use of two hands, and it's been a source of controversy in the past. e.g. Giri vs Epishin, Supercube Blitz Utrect, 2009 (scroll down to "The Incident").


How do I learn Chess Programming? Basically I have seen that people write a lot of chess algorithms, and ask questions in this forum, which I fumble to answer appropriately. I see the code, but unable to make out whether it is correct or not?

I am myself a software professional, but I am unfamiliar with chess algorithms, or coding-related stuff. Could you please help me to suggest where I can learn these things, or I will get the explanations ?

https://www.chess.com/blog/zaifrun/creating-a-chess-engine-from-scratch-part-1
http://mediocrechess.blogspot.com (a blog that gives you some ideas how chess engine works)

How you would approach the problem:

Check out chessprogramming.wikispaces.com. This'll be your reference site.
Create an account at talkchess.com. All the best engine developers are there. If there's an engine question that you can't find an answer there, you won't find it anywhere else.
Check out the TSCP engine source code. TSCP is a simpler but working implementation chess engine. Easier to read than Stockfish.
Do something. Try to write a chess board generator. Check the reference sites above. Study how TSCP does it.
Compare your PERF results with https://chessprogramming.wikispaces.com/Perft
Write a simple position evaluation with materials only. Copy the PST table from TSCP or the chessprogramming site.
Write a simple nega-max and alpha-beta search.
Read about UCI protocol
Add transposition table
Add simple null-move pruning


Is there a trick to help kids know which direction pawns are going? My 5-year-old old daughter very often forgets which direction a pawn is moving. This is confusing especially at endgame studies.

I use a marker pen to draw two eyes on the pawns so that her pawns are facing the enemy and their pawns are looking at her. But this is not applicable online and I am fearful of its side effect when she plays with others on an unmarked board later.

Any suggestions?

At 5 years old a child's brain is still very immature. The good news is that it is also developing very fast. The easiest and most effective solution is just to wait. Within a year or two the problem will have solved itself as your child's brain develops enough to satisfy your expectations.


Rating system for 5000 players we belong to a state in India with over 5000 active players. FIDE rating tournaments and FIDE rated players are here but we wish to start a new internal rating system like the USCF or ACF rating systems. Are there softwares or websites for this? Kindly advise

It seems that rankade, our ranking system for sports, games, and more, fits your needs.

It's free to use and it's designed to manage rankings (and stats, including matchup stats, and more) for small to large groups of players.

Rankade doesn't use Elo, but its algorithm (called ree algorithm), although more complex (here's a comparison between most known rating system, including Elo, Glicko and TrueSkill), is similar to Elo if you play 1-on-1 matches only.

On rankade (besides other sports and games) we host many chess groups, clubs, and associations.


When should you stop chasing a piece? I'm only a beginner, and I've found that sometimes a piece of mine (esp Queen) will just get chased around relentlessly causing problems, so I've started trying to do the same, but I seem to sometimes overextend and it feels like I am "following" not chasing.  Any advice on when to stop chasing?  What should I be looking for when deciding to chase or not?

Particularly bad example (playing Black)

[FEN ""]

1. f4 d5 2. d4 c5 3. Nf3 cxd4 4. Qxd4 Nc6 5. Qe3 d4 6. Qb3 Be6 7. Qxb7 Na5 8. Qb5+

If you chase an enemy piece, you should probably consider three aspects:

Basic tactical considerations.
Do you improve the position of the piece you use to chase the enemy piece?
Do you force the enemy piece on a worse or a better square?

In your example this means if you don't see that you are blundering pawns and pieces, all considerations of chasing or not chasing are pretty moot i.e. you have to think about whether you blunder something (like your b-pawn), whether your opponent blundered something (i.e. maybe you can already use his disorganised pieces for a tactical blow).

4…Nc6 was good, because you improve your knight and you chase the white queen away from a central square.

5…d4 is already somewhat more ambiguous because the queen is pretty bad on e3 (blocks the e-pawn) and probably better on b3 (attacks b7).

6…Be6 blunders the b7 pawn, but maybe you could have continued Bd5 to set up even more attacks on the queen, like Rb8 or a knight move. This starts to look dangerous for white, because you are building up a big development lead.

7…Na5 puts your knight on a worse square (knights on the rim...), so you'd need a good reason to do so and apparently you didn't have one.


What should be my approach to checkmating efficiently? [fen "r1bqk2r/ppp3Bp/2n5/8/1b2p3/1P2n1P1/P4PBP/RN1Q1KNR w kq - 0 13"]

I was playing a game where I got to this position as black on lichess.org - the analysis said that checkmate was unavoidable for white and it was a mate in 7. I played with it some more but I can't see the mate in 7.

I wonder what should be my approach to checkmating efficiently? Is it just by playing more games or are there some tips I should know?

Thanks

There are a fair number of lines toward the end that make the fact that mate is forced a little hard to spot, but it's certainly doable. A couple example lines:

[FEN "r1bqk2r/ppp3Bp/2n5/8/1b2p3/1P2n1P1/P4PBP/RN1Q1KNR w kq - 0 0"]

1.Ke2 (1.fxe3 Qxd1+ 2.Kf2 Qe1#) Qxd1+ 2.Kxe3 Qd3+ 3.Kf4 Bd6+ 4.Kg5 Qd5+ 5.Kh6 Bg4 6.Bxh8 (6.Be5 Qxe5 7.Bxe4 Bf8#) Qh5+ 7.Kg7 Qg6#

As for learning to spot these mates yourself, part of the trick is recognizing that Black's pieces are hugely more active than White's, especially after the White Queen is gone. Black should look to control the White King's movement easily with the two Bishops and the Queen, and mate is surely inevitable. Finding the fastest mate is always nice, but at the end of the day, any line will do as long as it doesn't provide an opportunity for White to escape!

When calculating mating lines (or any combination), it's easiest to look for forcing moves: moves which leave the opponent with only a single move, if possible. This naturally limits the number of lines you have to calculate. Good candidates for forcing moves are checks, or other threats which must be dealt with immediately. For instance, I found the line above by simply evaluating, at each step, the move that gives White as few resulting choices as possible. Even 5...Bg4 is a forcing move, because it threatens immediate mate via ...Qh5.


Longest sequence with only moves to draw without a repetition What is the longest known sequence of moves with upto 6 pieces where each move of
 both sides is the only move drawing the game (any other move would lose the game) ?

There should not occur any repitition of a position.

I experimented with the endgame rook vs two (three) pawns and got some
 sequences I unfortunately do not remember.

To get the ball rolling, from the following position the first 6 moves for each side are forced in order not to lose. (If 7.h8=B weren't available and 7.h8=Q needed to be played, then the forced follow-ups 7...h1=Q+ 8.Qxa1+ Kxa1 would extend it to 8, but no cigar.)

[FEN "K5R1/8/p7/8/8/7P/8/1q1k4 w - - 0 1"]

1.Rg1+ $1 Kc2 $1 2.Rxb1 $1 Kxb1 $1 3.h4 $1 a5 $1 4.h5 $1 a4 $1 5.h6 $1 a3
$1 6.h7 $1 a2 $1 7.h8=Q
    ( 7.h8=B )
7...a1=Q+ $1 8.Qxa1+ $1 Kxa1 $1 *


Do FIDE rules ban stimulants? Which ones? Do FIDE rules ban stimulants?   I think they ban 'drugs',  but would coffee be okay?   What about beer or wine?
I hope they ban smoking somehow now.
And I would think that NADH could help old grandmasters play much better.  Do not think there is any test for that either.
So what does FIDE ban and what can players take to stay alert  and play better ?

FIDE (and probably most of the national federations) would very much like chess to be an Olympic sport because that would lead to massive injections of money into the sport. Hence they subscribe to WADA and have defined drug testing protocols for chess.
The document Chess WADA – Anti-Doping Policy, Nutrition and Health gives details of banned substances relevant for chess:

The 2018 WADA Prohibited List and Monitoring Program can be found at:
http://list.wada-ama.org/
The most relevant banned substances for chess are:

Amphetamines – e.g. Adderall, Ritalin

Ephedrine and Methylephedrine – Prohibited by WADA when its concentration in urine is greater than 10 micrograms per milliliter

Pseudoephedrine is prohibited when its concentration in urine is greater than 150 micrograms per milliliter

Modafinil

Substances not present on the Prohibited List but represented in the Monitoring
Program:

Caffeine – Included in WADA Monitoring Program and relevant for incompetition testing only. Any urine test reading of less than 12 micrograms per milliliter poses no problem.
Codeine – A common ingredient in, for example, preparations used to treat coughs and stomach upsets. Any dosage is highly unlikely to be significant when taken in normal therapeutic quantities.

You say:

I hope they ban smoking somehow now.

Smoking is obviously banned in the playing area but is permitted in the playing venue if there is a designated smoking area. This is actually spelled out in the COMPETITION RULES section of the FIDE Laws of Chess:

11.3.4 Smoking, including e-cigarettes, is permitted only in the section of the venue designated by the arbiter

Not every tournament will have a designated smoking area although tournament organizers generally try and also not discriminate against smokers and vapers.

what can players take to stay alert and play better ?

The first and most obvious requirement for full mental alertness is adequate good quality sleep. FIDE has published its recommendations in Effects of Nutrition and Exercise on Cognitive Performance. There you will find FIDE's common sense guide to good nutrition and hydration.


A case where Bishop for knight isn't a good trade I have played recently a game. In the position below Stockfish is saying that Nxe6 is a mistake and Rad1 is suggested but I'm having a hard time figuring out why. Can someone provide some insights ? given these thoughts:

It's a bishop for knight in my favor.
The bishop makes my position slightly vulnerable because of the pin on the queen.
The knight outpost is appealing but it can be kicked with c5.

I played:

1r1q1rk1/ppn1bppp/2ppb3/8/2PNPBn1/1QN3P1/PP3PBP/R3R1K1 w - - 9 14

1. Nxe6 fxe6 2. Rad1

link of the game

it's a bishop for knight in my favor

So what? You will have moved the knight 3 times to your opponent's bishop 1 move and you will have improved your opponent's position by opening the f file for him. So, not in your favour after all.

  the bishop makes my position slightly vulnerable because of the pin on the queen

No, it doesn't. If it ever becomes a threat you can nullify it with NxB. Until it becomes a threat you are reacting to a phantom.

  the knight outpost is appealing but it can be kicked with c5

To which you can react with NxB! Again, you are reacting to a phantom. Although Ndb5 would be much better increasing the pressure on the backward and now weak pawn on d6.

The reason you won the game is that your opponent blundered. His reply to your Rad1 of moving the knight back to f6 for no good reason was terrible. Far better would have been to kick your bishop with e5. With the knight on g4 protecting e5 this is possible and very good. With the knight back on f6 this is not possible.

As is often the case the move you chose, NxB, releases tension unnecessarily, and in this case in your opponent's favour. Playing Rad1 retains the possibility of NxB if it looks better later and it reinforces the center and places a rook opposite black's queen. It is just a much better move.


Is castling legal in this position? Black to move in a game I just played. My rival and I were wondering about castling.

Exactly:

White bishop in D6 threatens B8. Is legal for black to make long (queen) castle? (Black king and rooks have not moved)
If white bishop were in E5 threatening H8, would be legal short (king) castle?

Position:

 [title "-"]
 [fen "r3k2r/pp1nnp2/2pB2pp/3p1p2/3P4/2N3PB/PPP1PP1P/R3K2R b KQkq - 0 1"]

Yes black is allowed to castle here. The castling would be invalidated if one of the squares along the path the king has to cross (e8 to g8 or e8 to c8) was under attack by an opponent piece. In your position, for example if the bishop was on c7, or a knight was on e6 then castling wouldn't be allowed. Whereas the bishop on d6 eyeing b8 only concerns the rook's path to complete castling, so long castling remains legal.

Similarly, if the bishop was on e5, by the same logic short castling would still be allowed.

 [title "Position"]
 [fen "r3k2r/pp1nnp2/2pB2pp/3p1p2/3P4/2N3PB/PPP1PP1P/R3K2R b KQkq - 0 1"]

 1...O-O-O


Who has the advantage in this position? I was in a three%day turn bame, I played almost played a line that would have led me to this position. Black’s central pawns seem to be an advantage, although White being up the exchange scared me. Who has the advantage in this position, and why?

It is White’s turn.

This position is not easy to assess.

Indeed, white has a rook, but black has a bishop and two pawns for it, which is roughly equal material-wise.

Also there are no open files, so white's rook do not have a straightforward way to enter black's position. The best white could currently do is to try to create counterplay against the pawn on e6 and create a blockade on the dark squares, preventing black from advancing the pawns. Since black does not have a dark squared bishop that should be reasonably easy to achieve.

As a long term plan, white can transfer his king to the queenside (e.g. to b2) and open some lines with g4, which does seem somewhat dangerous for black.

Still I think black is doing perfectly fine so far as the position is still closed, there are potential threats against g2 and the pawns are ready to run.

Overall I'd say the position is roughly equal (but interesting!).


Why is 5. Bd3 considered a strong move against the Kan variation? Why is 5. Bd3 considered a strong move against the Kan variation of the Sicilian Defense:

[FEN ""]
1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Bd3

You very rarely see the Bd3 move played against any other variation of the Sicilian...

The difference is that in the Kan white exchanges the knight on c6. In other sicilians this would be a concession, but here black has already played a6, which will not be particular useful after Nxc6 bxc6. In the other sicilians, if white doesn't exchange the Nc6, it will often go to e5 and threaten to exchange a Bd3, that's why the bishop often isn't well placed there. The plan connected to Bd3 is of course to play e5 sooner or later.


How can one precisely sacrifice a piece for a winning attack? r2qkb1r/5ppp/p1bppn2/1p3P2/4P3/1BN5/PPP3PP/R1BQ1RK1 b qk - 0 1

1... b4 2. fxe6! bxc3 3. exf7+

In the above game, black played 1...b4 to encumber the white knight's journey to d5. Ambitiously, white sacrificed it with 2. fxe6! bxc3 3. exf7+: attacking the uncastled king, claiming the f7 square as his, and trapping the king on the center files.

The inactivation of black's dark bishop justifies this sacrifice: it's not soon seeing daylight anytime. Similarly, the a8 rook is also passive; only the queen, light-squared bishop, and f6 knight appear to be able to defend a central onslaught.

The black king can move to either Kd7 or Ke7, which aren't ideal in the least: these squares lie on two semi-open files available for white to take advantage of.

Altogether, this convinces white that black's life is going to be a terrible time. Still, the development of the queen's bishop must occur for placement of the connected rooks on d1, e1. He can choose squares such as g5, pinning the queen, or move his bishop along the a3-f8 diagonal after a capture on c3.

White needn't checkmate, but he should return with, beyond question, a better position than black. What final position does white visualize that warrants the knight's goodbye?
There can be an overwhelming number of variations in realizing that final position: after 4. Re1, black has a number of responses. If this is the best move, how does white calmly reassure himself that all of its responses are inadequate? If it's not the best move, what is and why?

I am not looking for a final, deeply analyzed (e.g. best) variation, but a winning position and the most effective way to achieve it: the moves that should be played first, and why. A 3-ply variation is enough, but a 4-ply variation is perfect. Maybe I also missed some critical details about the board, and would welcome these observations, if any.

If this is the best move, how does white calmly reassure himself that all of its responses are inadequate?

White doesn't see a forced advantage in every line. He sees, what he believes to be, good winning chances. To quote Spielmann in The Art of Sacrifice in Chess:

  In real sacrifices the player gives up material but is unable to calculate the consequences with accuracy; he has to rely on intuition

  What final position does white visualize that warrants the knight's goodbye?

I think you answered your own question. After 2. fxe6 bxc3 3. exf7+ white probably thought that a lead in development and 2 pawns for the piece (potentially 3 if bxc3 is played) is sufficient compensation.

White doesn't have to look further than this if they are willing to take risks and figure out the attack 2 or 3 moves at a time. If white is risk averse, then they may not even consider 2. fxe6 bxc3 3. exf7+ at all.


Are there non-Chess games that use a chess board with "black on the right" Are there any non-Chess games that use a chess board where the bottom-right hand cell for each player is black rather than white?

In Spain checkers is played with the board placed that way. Alternatively you can place the board the same way as chess, but then pieces are placed at light squares.


What is the idea of 'ponder' in the UCI protocol? I've created my own chess engine and now I'm trying to connect it into the Chess Arena. Everything is actually working fine when I play them together (Demo). But I tried to play with it and didn't respond at my second move. So I looked at the console and there's this go ponder after my second move. Now I want to know: what's the idea of it?
I tried to go to this link for me to understand, but it's not enough. It says when I receive that command, I need to start searching in pondering mode. What exactly is start searching in pondering mode? Is it an infinite search that gets the best move for the opponent and only stops after I moved?
Let's say I move e2e4, engine plays e7e5. And then receives go ponder, after I move, let's say g1f3. And then the engine receives ponderhit and let's say the search completed depth 5 and result could be bestmove g1f3 ponder something. Now what happens if the bestmove g1f3 matches my move?

It's been a long time since I programmed anything, so I may be wrong.
Pondering, like in the comment, allows the computer to think on your time.  It basically switches sides and maintains a principle variation (PV search) (although I've seen some engines which maintain 3 PV searches) of what it considers to be the best line.  When you make your move, if it's the PV, then it should play the next move immediately.
The problem with ponder is the probability of having a wrong evaluation/incorrect line in the PV.  If the opponent's move was made quickly, the computer may have a random move in the PV, not really a possibility with modern computers searching a 3 million NPS, but older computers 20 years ago did have this problem.


Is it possible for a white piece to deliver check to the black king, but for black's counter move to result in white getting checkmated? Is it possible for a white piece to deliver check to the black king, but for black's counter move to result in white getting checkmated?

Has this happened in games between top players?

You can find some examples in the following game collection: Games where check is answered with checkmate.

Among those games, Nigel Short vs Alexander Morozevich, Russia - The Rest of the World (2002) is the only one that meets the qualification top players. This was a rapid game.

The most entertaining example is the following:

[FEN ""]
[Event "Philadelphia (m/7)"]
[Site "Philadelphia (m/7)"]
[Date "1945.??.??"]
[Result "0-1"]
[White "NN"]
[Black "Winkelman"]
[ECO "C29"]

1.e4 e5 2.Nc3 Nf6 3.f4 d5 4.fxe5 Nxe4 5.Qf3 Nc6 6.Bb5 Bc5
7.Nxe4 dxe4 8.Qxe4 O-O 9.Ne2 Re8 10.Bxc6 bxc6 11.Qxc6 Rxe5
12.Qxa8 Rxe2+ 13.Kd1 Bg4 14.Qxd8+ Re8# 0-1

There are also some additional examples in Edward Winter's Chess Notes: 4130, 4135.


syzygy tablebase generation program I am a linux user and have been able to write not-too-complex C programs.  I have also used makefiles. I have tried to download tablebase generator programs from GitHub but do not understand how to do this. The site seems to be primarily for programmers rather than users. I'm also not sure whether downloading source code costs money there.

First of all, everything on Github can be downloaded freely.  Normally, there should be a download button somewhere.  Do you have a specific project in mind sou want to download?  There seem to be several tablebase generators available.  One is available from https://github.com/syzygy1/tb it seems to have decent documentation.  There is a green button on the top right labeled "Clone or download", which allows you to download the whole thing as a zip file.  From there you will have to follow the provided instructions to compile it.  For questions on this another, more programming-related SE, may be more appropriate.


What is the weakest file on the board? If f2 and f7 are the weakest squares on the board, if the f-file the weakest file on the board? For example, other than attacking f2 and f7, is there a theoretical advantage in dominating the f-file?

The f2/f7 squares lose some significance after castling has occurred. The square is no longer protected by just the king - the rook now also protects it. But a f2/f7 pawn with a king on g1/g8 might be pinned by a bishop, which sometimes results in tactical opportunities.

Generally, you should attempt to control the center of the board. The f-file is not the center, but it is adjacent to the center. It might make sense to try to control the f-file if it is open or half-open (or if you plan to make it that way) but that's true of any open file.

If the file is not open or half-open, then it probably makes more sense to look at the individual squares rather than the file as a whole. If White has a pawn on e4, that pawn controls f5, but it also means that pawn can never control f4 (so f4 might be weak.)


Struggling to find a good opening with black? (Fide Elo 1950) Okay so, I'm rated around 1950 on the FIDE rating list, and I struggle finding a good opening with black so basically my game with white is more or less perfected (3 different openings where I learned tons of variations through practice and books) and with black I just keep improvising: whatever I do in serious games against 2100+ players gets me into a really passive position. So far I've tried out Robatsch (1. ... g6) or Pirc but both get me in really passive positions. 1. e4 bothers me most, because when it comes to d4 d5 is a decent response. Anyways I planned on playing the Scandinavian but it doesn't seem like grandmasters play it so it must have tons of flaws.French and Caro-Kann both seem passive so.. any suggestions? :/

Edit: With white I like playing the slightly modified London system (d4 without c4, g3 + lg2 etc) or english opening :)
Also, I studied 1. ...g6 quite some time and most times against stronger players i get pretty passive, but c5 and then e6 sounds kind of good. I'm naturally a positional player, i like strangling my opponents by small attacking, changing my weak bishop/knight and earning a pawn then taking it to the end, that's at least how most of my victories are, yet I have studied tactics excessively to improve on that as well :D thanks for you answers though!!

You say you've looked at most of the major defenses to 1. e4 except the two best, 1... e5 and 1... c5.

It sounds like what you're looking for is just about any Sicilian variation. Most of them require a lot of theory to not get killed on a regular basis but it sounds like you're fine with that. The Taimanov or Paulsen would be a good starting point because 2... e6 avoids White's 3. Bb5 tries that can be so annoying after 2... d6 or 2... Nc6.

If you have an aversion to the Sicilian for some reason, I wouldn't be so quick to reject the French or Caro-Kann. There is plenty of active play in each of them if you choose the right variations.


Are there any cloud engine services solely 'pay per use'? I'm looking for a chess cloud engine service where I only have to pay for the time I use.
I thought chessbase.com provides that, but you have to get a premium membership first (as far as I understand).
Nextchessmove.com and chessify.me require subscription as well.
Is anybody aware of an alternative that just bills per time used?

Lots of them let  you pay zero per use.
Download your own program and you only pay once.


Closed Sicilian Problem if Black Fianchettoes His Light-Squared Bishop Help! Please.

After Bb7, I often play f4, followed by g4-g5 and h5. But the Bishop at b7 always gives me problems because it seems that my position after playing f4 will be too open after Black exchanges some pawns in the center and my kingside can be attacked easily.

I've been searching for several books but all books that I have seen so far on Amazon or chessbase.com only cover the variation where Black either fianchettoes at the kingside only or the variation where Black fianchettoes both Bishops. I am only interested in the variation where Black doesn't fianchetto in the kingside but fianchettoes in the queenside.

After the last move by Black. I am often confused where to put my a-Rook. When I push d4-d5 after few moves, my opponent often maneuver his Knight to c4 via a5, attacking my Queen and Bishop. Or in some cases, after playing f5, my opponent puts his Knight to e5 since it cannot be attacked by the f-pawn anymore. What is the common plan for White in this position? What should I do with Black's b7-Bishop?

[fen ""]

1. e4 c5 2. Nc3 Nc6 3. g3 e6 4. Nge2 d6 5. Bg2 a6 6. O-O Qc7 7. d3 Be7 8. Be3 Nf6 9. h3 {Preventing Black from harrassing my Bishop} O-O 10. Qd2 b5 11. a3 Bb7

I think one of the biggest issues with the Closed Sicilian is that many players of the white pieces often feel that they should somehow be able to roll Black off of the board. However, if Black seeks active counterplay, such as the expansion on the Q-side with ...a6 and ...b5, then he is usually equal, if not slightly better.

Once the stereotypical moves of the closed Sicilian are made by white, the position is usually equal, and it's up to white to either outplay his opponent, or get dominated on the Q-side. Your line isn't a bad line, it's just that with the majority of your pieces located on the K-side, Black will usually have more than sufficient Q-side counterplay.

One of the reasons why many people play Open Sicilians is because it allows more variety on how you want to play the position, and often, which side of the board you want to play on. The closed Sicilian, in the manner that you played it, for the most part, only leaves you with one option. A K-side attack that can be negated with a few adjustments. Once Black counters that strategy, you are simply left with an even position where you may even have to relocate your pieces to the Q-side. Even more difficult to have to find a strategy for...at any given moment, Black will get in the move ...d5, followed by a possible ...f6 at some point as well. This position doesn't really hold any dangers for Black unless he grossly misplays it.


Disappointing Drawn Game Analysis I recently played a not-so-good tournament, my US rating is a little under 1900, and this is a game where I had a draw against a 1600 player that reminds me of how I played when I was 1700. My opponent showed up 45 minutes late and unfortunately I let that get to me psychologically, and started having a bit of an impatient attitude while playing. This caused me to make some positional mistakes that I shouldn't have been making. So I have a few questions in the game PGN, if you guys could answer those and point out anything else that's important, I'd appreciate it. Thanks!

 [fen ""]
 [Event "Michigan Amateur"]
 [Date "6/2/2018"]
 [Round "3"]
 [White "Brandon O'Neil"]
 [Black "Raymond Burwell"]
 [Result "1/2-1/2"]
 [WhiteElo "1896"]
 [BlackElo "1600"]
 [ECO "A13"]
 [Opening "English Opening: Agincourt Defense"]

 1. c4 e6 2. g3 f5 3. Bg2 Nf6 4. Nc3 Be7 5. Nf3 d6 6. d4 O-O 7. O-O c6 8. d5!? { I thought I could take advantage of black's slow development, but I ended up shutting in my bishop eventually. Should I be more patient and play something like 8.Qc2? I think 8.d5 could work if I follow up well. } (8. Qc2) 8... e5 9. Qb3? { Played quickly and impatiently. This move allows black to close the center, allowing me to shut in my bishop. Would 9.c5 be the best try? } (9. c5) 9... c5 10. e4 (10. Bh3 { Maybe if I followed this move with e4, I could try to trade my bad bishop, but is that really worth it with the weakening of my light squares? }) 10... Nxe4 11. Nxe4 fxe4 12. Nd2 e3 13. Qxe3 Bg5 14. Qc3 Bxd2 15. Bxd2 Qf6 16. b4 { Doesn't seem like this really accomplished anything. Maybe 16.f4 straight away? } (16. f4) 16... b6 17. a4 Na6 18. bxc5?! { It seems to me that this really helped black with his central influence. 18.b5 seems more limiting, and then I could follow with a5. } (18. b5 Nc7 19. a5) 18... Nxc5 19. a5 Bf5 20. f4 exf4 21. Qxf6 Rxf6 22. Bc3 Rff8 23. Rxf4 Bd3 { The after-effects of not playing 9.c5 start to show more. } 24. Rxf8+ Rxf8 25. axb6 axb6 26. Ra7 Rf7 27. Ra8+ Rf8 28. Rxf8+ { In hindsight, I should have realized how bad this ending is for me and repeated rook moves. } (28. Ra7) 28... Kxf8 29. Bf1 Be4 30. Kf2 Bxd5 31. Bxg7+ Kxg7 32. cxd5 Kf6 33. Bc4 { Bishop in front of the pawn (on c6) is probably a more solid setup. } 33... Ke5 34. Ke3 Nd7 { Already having trouble defending my central pawn. } 35. g4 Nf6 36. g5 Ng4+ 37. Kf3 Kf5 38. Bd3+ Kxg5 39. Bxh7 Nxh2+ 40. Ke4 Ng4 41. Kd4 Kf4 42. Bd3 Ne5 43. Bb5 Nf3+ 44. Kc4 Ke5 45. Bc6 { Seems like I'm safe now. } 45... Nd4 46. Kb4 Ke4 47. Bb7 Nc2+ 48. Kb5 Ne3 49. Kc6 Nc4 50. Kb5 Kd4 51. Bc6 Ne3 52. Kxb6 Nxd5+ 53. Kb5 Nc3+ 54. Kb6 Kc4 { My opponent wants to stubbornly play out this drawn ending, so the rest of these moves aren't too important. } 55. Bh1 Kd4 56. Bg2 Ne4 57. Bf1 d5 58. Ba6 Ke5 59. Ka5 d4 60. Kb4 Nd2 61. Bd3 Kf4 62. Ba6 Ke3 63. Bb5 Nf3 64. Ba6 Kd2 65. Bb5 Ne1 66. Kb3 Nc2 67. Ba6 Ne3 68. Bb5 Ke1 69. Ba6 Kf2 70. Bb5 Kg3 71. Kb4 Kf4 72. Ba6 Ke5 73. Bd3 Kd5 74. Ba6 Nf5 75. Bb7+ Ke5 76. Ba6 Nd6 77. Bd3 Kd5 78. Ba6 Ke4 79. Kb3 Ke3 80. Kb4 Ne4 81. Bb5 Nd2 82. Ba6 Ne4 83. Bb5 d3 84. Bxd3 1/2-1/2

If your rating is 1900, this game must have been quite disappointing. But it also seems to me that Black played well above 1600-level.

7...c6 is a rare move, but not so bad that you should look for an immediate refutation. 8.Qc2, intending to open the center with e2-e4 (either fast or after b3-Bb2) is indeed very logical. If Black goes for d6-d5, he is one whole tempo down compared to the Stonewall with Be7 (which is already considered a bit passive for Black); then your plan could be Rb1,b4-b5, Bf4, Rfc1 with initiative on the Q-side. If Black refrains from d6-d5, you open the e-file with e2-e4, build pressure on e6 and fianchetto your dark squared bishop. Black only plan to finish development seems to be Na6-c7 and Bd7, but then he still have problems to solve: his queen has no great square and d6 is unprotected (can be targeted by Ba3, for instance).
I don't think 9.c5 would have acheved much more than what you got in the game. After 9...e4 the most plausible scenario is a complete swap of c- and d-pawns, after which your space advantage has vanished. 9.Qc2, 9.b3 or 9.e4 would be my main candidate moves here: you still have to complete development.
I don't believe in 10.Bh3. Sure, exchanging light-squared bishops is formally good, but it wastes time (Bg2 moves again and Bc8 has not used any tempo), weakens your king (because you've played g3, Black's eventual kingside attack with f5-f4 can be very dangerous even without a ...Bc8xh3 idea) and Black doesn't even have to allow it (he can also defend f5 with g6 and develop slowly, either with Na6-c7, Bd7 or Nh5-g7, Nd7-f6).
If I was Black, I would have given some thoughts to the pawn sac 10...f4 11.gf4 Nh5 12.fe5 Bg4, but White is clearly on top after 12.f5!
After 15 moves the position is almost equal, the bishop pair doesn't mean much with a closed center and you lack a knight to post on e4. 16.b4?! and 16.f4?! are both hurrying too much, you should slowly build some pressure with a3-b4-Rb1-Be3 with a slow, manoeuvering game.
Black should absolutely take 16...cb4 17.Qb4 Na6 and 18...Nc5, catching up in development and with the same excellent knight he got later. Similarly, after his erroneous 16..b6?, 17.bc5 is very tempting when he has to take back with a pawn. 17...dc5 would be good if the knight could reach d6, but it is just bad because you will target Pe5 and Pb6 (with a4-a5) long before. After the correct 17...bc5 18.Rb1, you have good chances of exploiting your lead in development, either with Qa5-c7 or f2-f4.
17...cb4 18.Qb4 Na6 19.Qb2 Nc5 20.a5! is less clear than one move before, but it's still better for Black than what he did.
After 17...Na6? you should absolutely go for it with 18.b5! Nc7 (18...Nb4 is a not-totally-convincing pawn sac after 19.Qb3) 19.a5! Bd7 (or Rb8 20.ab6 ab6 21.Ra7) 20.Ra2, etc... Note how bad Black's Nc7 and Bd7 are compared to his Nc5 and Bf5 in the game. 18.bc5? is maybe your worst move in this game.
20.f4 is the typical pseudo-active move we all play when we feel something has gone wrong. But here I've nothing much better to suggest, maybe doubling on the a-file was more stubborn ?
I feel like after 20...Bd3!? Black will end up picking Pc4, say after 21.fe5 Qe5 22.Rf8 Rf8 23.Qe5 de5 24.ab6 ab6. Then you will possibly save a draw thanks to his own weak pawns (much like in the game). But compared to the game, you each have gained a passed pawn in the process, which makes the game sharper. Moreover, 20...ef4 is probably very imprecise because...
...Was 22.ab6! possible ? Looks like your passed pawn on the Q-side will turn the table.
The draw on move 28 would have been a fair result.
30.Bd4 avoids Black's small combination and preserve your bishop pair. After 30.Kf2? you're in serious danger.
Was 36...Nxd5! possible ? With the extra pawn it looks like Black is winning.
The Bishop vs knight endgame with 2 vs 1 looks indeed drawn. You are a bit lucky at the end: in case of 41...Nf6 42.Bd3 Ne8 43.Bb5 Nc7 (attacking d5 and blocking b5 for the wK), you have just two squares to wait with the bishop, so that there is no zugzwang and your king can stay on d4: 44.Bc6 Kf4 45.Bb7 Kf5 46.Bc6, you never allow ...Ke5, draw.

(Comments without engine, since I believe that's what you are looking for. But there may be some tactical flaws in the lines above...)


Which countries are easiest to gain rating points and earn FIDE titles in? I recently played in a tournament in Iran (Fajr Cup, u2000), where 1600-rated players were a serious threat, and 1400-rated players would fight to the last pawn.  I don't think a single opponent of mine made significant tactical errors--they know how to calculate.  In my opinion, these players are vastly underrated, maybe by 300+ rating points.  I also play in China, which is also considered an underrated country (but Iran seems more underrated).

Players suggest countries for relatively easy rating points and FIDE title norms: A WGM suggested France or Spain, and a WFM suggested Turkey to me.  I'm tempted to go norm hunting, but I wonder where.

Question: Which countries are easiest to gain rating points and earn FIDE titles in?

I'm after something a bit more concrete than some random countries, e.g., the usual places players go to get rating points and norms.

Rating is a lagging indicator. That is, it gives an estimate of playing strength in the past. Therefore by definition players who are improving are underrated and players who are declining in strength are overrated.

Therefore as a first step if you can enter late you should look at the age profile of the entries and avoid entering tournaments with lots of very young players (who are likely to be still improving) and try and enter tournaments with old (preferably senile :-)) players (who will likely be on the decline).

Looking at the raw FIDE rating data which FIDE supply from January 2019 (I haven't yet loaded the latest February data in my database) and running a query gives the following results for average Date of Birth year for active players in federations with at least 1000 active players -

P 1. Denmark - 1966.4
 2. Netherlands - 1969.5
 3. Switzerland - 1970.95
 4. Finland - 1972.8
 5. Austria - 1974.2
 6. Germany - 1974.6
 7. Serbia - 1974.8
 8. Sweden - 1976.1
 9. Ireland - 1976.2
 10. Bosnia Herzegovina - 1976.7
 ...
P 22. Spain - 1984.9
P 23. Australia - 1985.2
 ...
P 34. France - 1986.9
 ...
P 56. Iran - 1992.6
 ...
P 70. India - 1997
P 71. Turkey - 1997.8
 ...
P 76. China - 1999.2

So, for best results try and enter tournaments in countries at the top of the list and avoid countries at the bottom.

Note that Spain and France are not much different to Australia and Turkey is on a par with India - far too young!


How to play vs. 1.e4 e5 2.Nf3 Nc6 3.Bc4 d6? As title above, how to play vs.

[fen ""]

1.e4 e5 2.Nf3 Nc6 3.Bc4 d6

I see that this move (3...d6) is generally considered inferior in books, or not even mentioned in books about 3.Bc4, but I cannot see a clear way to obtain advantage.

The game will get the characteristics of the Philidor Defense rather than the Italian Game. Wikipedia calls it the Semi-Italian Opening.

  I. A. Horowitz called the defence "solid", also writing: "It does not seem quite sufficient for equality."

The Wikipedia article notes several possible continuations for White, with 4. d4 probably the best bet for advantage.


Is playing slow necessarily bad? I play online chess on under 5+0 and 10+0(predominantly) time controls. I end up in time problems way too often (especially in 5 minutes TC). I contemplated a lot on certain positions, and somehow lose track of time due to it. I have played 10+0 time control for 95% of my chess playtime, and have gotten accustomed to it. I am rated 1800+ in rapid (10+0) but only at 1500+ in blitz (5+0). Mostly I lose blitz as I end up losing time in the beginning, and then speed up my play in the end (just to prevent flagging) leading to a blunder.

So is playing slow a bad thing in chess?

I saw Magnus Carlsen (in a livestream) say that he doesn't play 5+0 as it is way too long for him! So I wonder will the pace of my moves increase, as I get stronger. Or is it something that needs to be dealt separately. And are there any ways to improve it right now?
P.S.:- Most of my matched in 10+0 result in a win/loss (doesn't usually get flagged). And that win/loss seems a lot more appreciable as it is more justified.

Playing slowly depends on the time format of the game, If you are playing a bullet time format and you play slow, then you will make very few moves and time will run out before you checkmate your opponent. If you are playing a 90mins game and you play fast, then you will probably get checkmated and spent the next 75 mins waiting for the next tournament round to start...
There are both merits and demerits of analyzing a position too much.
Consider below position
[Event "Bled-Zagreb-Belgrade Candidates (1959)"]
[Site "Bled, Zagreb & Belgrade YUG"]
[Date "1959.26.10"]
[Round "27"]
[White "Robert James Fischer"]
[Black "Mikhail Tal"]
[Result "0 - 1"]
[SetUp "1"]
[FEN "1q2kbr1/p3rp1p/8/1p6/8/5Q2/PPP3PP/R4R1K w - - 0 1"]

1. Qc6+ (1. Rae1) *

In the above position Fischer analyzed the position for a while, and had a move that could draw the game, he even wrote the move down (This may not be the practice today) but ended up playing a different move. Rae1 would have secured him a draw but the move he played Qc6+ cost him the game. So if he had not analyzed the game too much he would have drawn this game
I believe it is Magnus Carisen who said that sometimes he knows the move he will make but still analyzes the position even more on long games. For short games like blitz, if you know the move, make the move
Consider this position
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "r5k1/5ppp/5b2/2R5/8/6P1/5PBP/6K1 b - - 0 1"]

1... Ra1+ 2. Bf1
(2. Rc1) *

Is there need to think about the next move? There are only two moves, one is just giving out a rook. If you are playing a blitz game for example and there is only one move possible, play that move
Some positions may require more analysis, consider the below position
[FEN "1r2k2r/p4ppp/2b3n1/1pRBB3/8/8/PP3PPP/5RK1 b - - 0 1"]

1... Nxe5 *

How does white continue? Depending on how complicated the position is, there may be need to spent more time.
Now what if you have too many options at your disposal?
[FEN "5r1k/ppbq1np1/2n1rp1p/8/2PP3N/2NBP3/2Q2BPP/R3R1K1 w - - 0 1"]

In a blitz game I take the 1st good option and make it but if I have time, I can think about the position


Memorizing the board I'm always experiencing difficulties while trying to visualize what moves a tutorial (or an answer here for that matter) is talking about unless I have a chessboard with coordinates nearby.

Is this something I should fix, or is it fine to be using a chessboard? and what can you advise someone who want to memorize it?

The easiest way to visualize the board is to practice!  I know that sounds trite, but there aren't really all that many shortcuts.  Go over games in magazines.  Start from one of the positions given as an image and then "make" as many moves as you can in your head.  Try to see the position and look for the threats and ideas of each move.  If you can only make one move, that's fine - it's a good start.

Similarly, you can use a physical board when you're going over a game.  Play out the moves on the board and start to learn the squares by name as opposed to figuring out which square is which each time.  That's probably the first step.  After you know the "names" of the squares, the rest will start to fall into place.


Plan to proceed in this position I have a position which the engine gives as favorable for black (black to move), but I am confused on what plan should black adopt, as white has a dangerous passed pawn and black doesn't; also exchanging the queens doesn't look good as the black knight is too slow to catch the white pawn.

Let's check forcing moves first.

1... Qxf2 is definitely draw.

[FEN "8/8/8/2p1p3/2Pp2P1/1knP4/3q1QK2/5B2 b - - 0 1"]

1... Qxf2 2. Kxf2 e4 (2...Kc2 { transposes to main line}) {Nd1, or Na4 too slow, so e4 is the only option. Kc2 transposes to this line.} 3. Kg3! (3. g5? Kc2 {Both sides queen, but black remains with extra pawns, winning for black}) (3. dxe4? Nxe4+ {Threatening with fork, if Black exchanges minor pieces, it's a winning pawn endgame for Black} 4. Ke1 Kc3-+ {White has to give up bishop for d pawn, and White's pawn is going nowhere} (4. Kg1 Kc3-+ {White has to give up bishop for d pawn, and White's pawn is going nowhere}) (4.Kg2 Kc3-+ {White has to give up bishop for d pawn, and White's pawn is going nowhere}) {White has to give up bishop for d pawn, and White's pawn is going nowhere}){Not letting Black to get tempo while marching to queen} Kc2 4. dxe4 d3 5. Bxd3+ Kxd3 6. Kf4 Nxe4 7. Ke5=/= {Lomonosov}

So we know that Black at least has draw. But I feel Black should win in this position. Bishop is not active, but knight is doing very good, especially when it lands to e3. Also Black's king is very active, can easily eliminate White's remaining pawns if both sides queen. So, Black probably has a winning continuation.

Some ideas:

[FEN "8/8/8/2p1p3/2Pp2P1/1knP4/3q1QK2/5B2 b - - 0 1"]

1... Qc1 {This move feels best for me. It puts the queen to h6-c1 diagonal to block white pawn which I think important. Qg5 is an alternative} (1...Qg5) 2. Qg3 {Attacking e-pawn, supporting b-pawn} Nd1 {Knight is heading to e3} 3.Be2 {Activating bishop, not much alternative though} Ne3+ 4. Kf2 Kc3 { Attacking d3} 5. Qxe5 Kd2 { Threatening Qe1, taking bishop} 6. Qh2 { Defends bishop } Qe1 7. Kf3 Nxg4 {Wins a pawn} 8.Qf4 Ne3 {Bishop is hanging again} 9. Qh2 Qb1

Resulting position looks very promising for Black. But of course, the line is not forced, so, this continuation may not be the best. Anyway, it should give an idea to decide how to proceed in starting position.

Conclusion

I believe, Black should not play 1...Qxf2, instead should look for a win. Black should centralize the knight to e3 square, put the king into c3, where it attacks d3, should try to force White to give up g-pawn by pressing on g-pawn and bishop same time, knowing that bishop is blocked by allied pawns, and pretty much stands as a target to attack in White's crampy king-side.

Testing my Findings with Monte Carlo Simulation

I run a 10 game Manto Carlo simulation where each side has 10 minutes to finish the game. In all games, black went for the line above, starting with ...Qc1, and won all games.

[Event "?"]
[Site "?"]
[Date "2015.12.28"]
[Round "1"]
[White "Stockfish 261014 64"]
[Black "Stockfish 261014 64"]
[Result "0-1"]
[FEN "8/8/8/2p1p3/2Pp2P1/1knP4/3q1QK1/5B2 b - - 0 1"]
[PlyCount "67"]
[SetUp "1"]
[TimeControl "100/600"]

1... Qc1 { +1.68/24 11s}  2. Qg3 { -1.63/25 12s}  2... Nd1 { +2.40/25 7.4s}  3.
Be2 { -2.36/25 15s}  3... Ne3+ { +2.57/24 7.4s}  4. Kf2 { -2.68/25 12s}  4...
Kc3 { +2.71/25 11s}  5. Qxe5 { -2.85/26 14s}  5... Kd2 { +3.28/27 11s}  6. Qh2
{ -3.47/27 17s}  6... Qe1+ { +3.34/26 7.4s}  7. Kf3 { -3.47/1 0.001s}  7...
Nxg4 { +3.58/27 15s}  8. Qf4+ { -3.47/25 7.2s}  8... Ne3 { +3.58/28 7.3s}  9.
Qh2 { -3.75/25 17s}  9... Qb1 { +3.87/26 40s}  10. Kf2 { -3.05/25 7.1s}  ( 10.
Bf1+ { -3.72/27 30s}  10... Kc3 { +3.72/26 5.7s}  11. Be2 { -3.40/27 6.9s}
11... Qb6 { +3.96/26 17s}  12. Kf2 { -3.80/22 23s}  12... Qf6+ { +5.22/27 17s}
13. Kg1 { -4.60/25 14s}  13... Qg5+ { +5.67/28 12s}  14. Kf2 { -4.97/25 33s}
14... Nf5 { +5.88/29 5.3s}  15. Qh3 { -4.93/23 8.4s}  15... Qf4+ { +6.20/25
7.2s}  16. Qf3 { -4.55/26 9.6s}  16... Qh4+ { +10.93/36 49s}  17. Kg1 {
-4.42/26 6.2s}  17... Ne3 { +28.79/28 7.8s}  18. Qf2 { -52.13/37 17s}  18...
Qxf2+ { +52.11/36 7.1s}  19. Kxf2 { -62.24/39 13s}  19... Kd2 { +54.84/37 4.6s}
 20. Bf3 { -89.07/39 19s}  20... Kxd3 { +58.23/38 32s}  21. Bh5 { -123.53/38
9.0s}  21... Nxc4 { +62.79/41 5.9s}  22. Bd1 { -123.53/37 5.7s}  22... Kc3 {
+M73/35 8.8s}  23. Bg4 { -298.86/37 19s}  23... d3 { +M69/35 8.1s}  24. Ke1 {
-M42/36 44s}  24... d2+ { +M47/35 8.8s}  25. Kf2 { -M36/37 17s}  25... Nb2 {
+M35/36 3.9s}  26. Ke3 { -M34/37 14s}  26... d1=Q { +M31/36 7.0s}  27. Bxd1 {
-M32/36 4.4s}  27... Nxd1+ { +M29/36 3.9s}  28. Ke2 { -M26/36 9.0s}  28... Kc2
{ +M27/35 3.8s}  29. Ke1 { -M24/35 9.8s}  29... c4 { +M25/34 3.8s}  30. Ke2 {
-M22/35 4.1s}  30... c3 { +M21/34 3.8s}  31. Ke1 { -M20/33 7.8s}  31... Kb2 {
+M19/33 3.8s}  32. Kxd1 { -M18/42 5.4s}  32... c2+ { +M17/40 3.7s}  33. Ke2 {
-M16/51 3.9s}  33... c1=Q { +M15/48 3.7s}  34. Kf2 { -M14/66 5.4s}  34... Qf4+
{ +M13/71 3.7s}  35. Kg2 { -M12/120 4.0s}  35... Kc3 { +M11/120 3.0s}  36. Kh3
{ -M10/120 0.31s}  36... Kd2 { +M9/120 0.079s}  37. Kg2 { -49.17/1 0.001s}
37... Ke2 { +M7/120 0.015s}  38. Kh3 { -M6/120 0.039s}  38... Qg5 { +M5/120
0.012s}  39. Kh2 { -M4/1 0s}  39... Kf2 { +M3/120 0.005s}  40. Kh3 { -M2/120
0.001s}  40... Qg3# { Stockfish 261014 64-Stockfish 261014 64 2015.12.28}  ) (
10. Bf1+ { -3.74/26 29s}  10... Kc3 { +3.81/25 47s}  11. Be2 { -3.25/26 6.9s}
11... Qb7+ { +3.87/26 32s}  12. Kf2 { -3.57/27 11s}  12... Qb6 { +3.93/26 40s}
13. Ke1 { -3.57/25 22s}  13... Qf6 { +8.13/28 7.3s}  14. Qf2 { -6.34/27 13s}
14... Qg6 { +13.22/29 11s}  15. Qh2 { -14.05/28 14s}  15... Qg2 { +21.86/33
7.4s}  16. Qxg2 { -39.84/32 10s}  16... Nxg2+ { +52.18/37 6.6s}  17. Kf2 {
-57.87/37 13s}  17... Nf4 { +54.92/37 4.5s}  18. Bf3 { -64.66/38 40s}  18...
Nxd3+ { +61.64/38 13s}  19. Kg3 { -73.95/38 16s}  19... Nb2 { +123.52/38 6.1s}
20. Kf4 { -123.13/37 52s}  20... d3 { +123.55/37 9.1s}  21. Bg4 { -123.19/36
13s}  21... d2 { +123.56/36 6.3s}  22. Ke3 { -74.63/34 44s}  22... d1=Q {
+298.95/34 4.3s}  23. Bxd1 { -M40/33 5.8s}  23... Nxd1+ { +M33/35 8.1s}  24.
Ke2 { -M32/36 6.5s}  24... Nb2 { +M31/35 4.2s}  25. Ke3 { -M30/35 7.3s}  25...
Kxc4 { +M27/35 4.5s}  26. Kd2 { -M26/35 8.2s}  26... Kb3 { +M25/34 4.2s}  27.
Ke2 { -M24/33 5.3s}  27... c4 { +M23/31 4.2s}  28. Ke3 { -M22/31 7.2s}  28...
c3 { +M21/32 4.2s}  29. Kf3 { -M20/30 5.2s}  29... c2 { +M17/29 4.2s}  30. Ke4
{ -M16/30 6.5s}  30... c1=Q { +M15/30 4.8s}  31. Kf5 { -M14/32 6.6s}  31... Qh6
{ +M13/33 4.7s}  32. Kg4 { -M12/42 4.8s}  32... Qg6+ { +M11/41 4.3s}  33. Kf4 {
-M10/112 4.8s}  33... Nd3+ { +M9/106 4.1s}  34. Ke3 { -M8/120 0.047s}  34...
Qf5 { +M7/120 0.10s}  35. Ke2 { -M6/120 0.013s}  35... Kc2 { +M5/120 0.014s}
36. Ke3 { -M4/1 0s}  36... Qf4+ { +M3/120 0.003s}  37. Ke2 { -M2/1 0.001s}
37... Qf2# { Stockfish 261014 64-Stockfish 261014 64 2015.12.28}  ) ( 10. Bf1+
{ -3.65/24 17s}  10... Kc3 { +3.73/26 12s}  11. Be2 { -3.80/25 11s}  11... Qb7+
{ +3.73/28 7.1s}  12. Kf2 { -4.55/26 18s}  12... Qg7 { +3.73/28 7.2s}  13. Qg3
{ -3.92/24 19s}  13... Qf6+ { +4.37/23 12s}  14. Kg1 { -4.20/26 23s}  14... Kd2
{ +5.05/25 37s}  15. Bf3 { -4.20/26 6.6s}  15... Kxd3 { +5.05/26 14s}  16. Qf2
{ -4.76/22 37s}  16... Qf5 { +5.11/26 6.6s}  17. Qe2+ { -4.76/22 6.1s}  17...
Kc3 { 0.00/1 0.001s}  18. Qe1+ { -5.27/22 17s}  18... Kxc4 { +5.82/23 15s}  19.
Kf2 { -6.03/21 13s}  19... Kb3 { +6.00/23 9.7s}  20. Qa1 { -6.72/23 22s}  20...
Qc2+ { +6.13/23 22s}  21. Kg3 { -6.40/25 51s}  21... c4 { +6.74/22 14s}  22.
Qa8 { -7.67/22 19s}  22... Qg6+ { +9.13/21 10s}  23. Kh3 { -8.36/23 7.0s}
23... Qh6+ { +12.94/23 14s}  24. Kg3 { -11.10/25 24s}  24... Qg5+ { +13.89/24
9.6s}  25. Kh3 { -7.31/25 4.2s}  25... d3 { +14.70/25 19s}  26. Qa1 { -11.77/21
17s}  26... Kc2 { +33.72/23 10s}  27. Qa2+ { -17.01/20 7.4s}  27... Kc1 {
+49.10/26 19s}  28. Qf2 { -26.58/22 11s}  28... d2 { +62.82/27 5.4s}  29. Be2 {
-M38/25 17s}  29... c3 { +M33/25 7.6s}  30. Qf8 { -49.06/24 11s}  30... d1=Q {
+M31/27 9.2s}  31. Bxd1 { -M36/25 4.6s}  31... Kxd1 { +M27/29 5.2s}  32. Qf1+ {
-M24/32 7.0s}  32... Kd2 { +M23/32 10s}  33. Qf2+ { -M22/31 7.5s}  33... Kd3 {
+M21/35 4.9s}  34. Qf1+ { -M20/28 5.3s}  34... Ke4 { +M19/36 4.9s}  35. Qh1+ {
-M18/31 2.9s}  35... Qg2+ { +M17/39 4.8s}  36. Qxg2+ { -M16/44 2.8s}  36...
Nxg2 { +M15/56 4.7s}  37. Kg4 { -M14/58 3.8s}  37... c2 { +M13/71 4.7s}  38.
Kg5 { -M12/46 3.8s}  38... c1=Q+ { +M11/92 4.6s}  39. Kf6 { -M10/80 3.6s}
39... Qc6+ { +M9/120 1.9s}  40. Kg7 { -M8/120 0.58s}  40... Kf5 { +M7/120
0.20s}  41. Kh7 { -M6/120 0.013s}  41... Qc7+ { +M5/120 0.008s}  42. Kh6 {
-M4/120 0.003s}  42... Qb7 { +M3/120 0.003s}  43. Kh5 { -M2/1 0s}  43... Qh7# {
Stockfish 261014 64-Stockfish 261014 64 2015.12.28}  ) ( 10. Bf1+ { -3.84/28
67s}  10... Kc3 { +3.69/26 18s}  11. Be2 { -3.87/24 9.6s}  11... Qb7+ {
+3.97/25 14s}  12. Kf2 { -4.03/25 9.0s}  12... Qf7+ { +4.16/27 12s}  13. Kg1 {
-4.14/25 15s}  13... Qg7+ { +4.16/27 6.4s}  14. Kh1 { -4.62/26 37s}  14... Qb7+
{ +4.16/26 18s}  15. Kg1 { -3.02/22 8.3s}  15... Qb1+ { +4.46/27 56s}  16. Kf2
{ -3.52/23 14s}  16... Kd2 { +4.46/28 5.6s}  17. Kf3 { -3.80/24 12s}  17...
Qb7+ { +5.02/27 9.0s}  18. Kf2 { -3.94/25 12s}  18... Qf7+ { +5.02/27 5.6s}
19. Kg1 { -5.23/28 7.7s}  19... Qg6+ { +5.29/26 15s}  20. Kf2 { -5.35/29 11s}
20... Qf5+ { +5.94/26 25s}  21. Kg1 { -5.35/31 5.4s}  21... Qg5+ { +5.94/26
5.1s}  22. Kf2 { -5.99/30 49s}  22... Nf5 { +6.08/27 5.1s}  23. Bf3 { -6.03/23
7.5s}  23... Kxd3 { +6.43/26 13s}  24. Qh3 { -5.35/23 11s}  24... Kc3 {
+10.82/26 23s}  25. Qg4 { -4.73/21 8.8s}  25... Qxg4 { +60.25/35 7.2s}  26.
Bxg4 { -54.79/32 6.8s}  26... Ne3 { +M57/34 4.6s}  27. Bf3 { -123.56/34 9.2s}
27... Nxc4 { +298.91/34 7.5s}  28. Kg3 { -102.45/34 4.5s}  28... d3 {
+298.93/33 4.5s}  29. Kf4 { -298.98/31 6.1s}  29... d2 { +M71/34 18s}  30. Ke4
{ -122.62/33 37s}  30... Nb2 { +M43/34 9.4s}  31. Ke3 { -M36/34 10s}  31...
d1=Q { +M37/34 4.1s}  32. Bxd1 { -M32/35 3.8s}  32... Nxd1+ { +M29/35 4.0s}
33. Ke2 { -M26/36 4.5s}  33... Kc2 { +M27/35 4.0s}  34. Ke1 { -M28/33 3.2s}
34... Nc3 { +M25/35 4.1s}  35. Kf2 { -M26/33 3.1s}  35... Kd3 { +M23/34 3.9s}
36. Kf3 { -M22/32 4.8s}  36... c4 { +M21/32 3.9s}  37. Kg4 { -M20/32 4.0s}
37... Ne4 { +M19/32 5.4s}  38. Kf4 { -M18/34 4.1s}  38... c3 { +M17/34 3.7s}
39. Kf5 { -M16/35 4.4s}  39... c2 { +M15/35 3.6s}  40. Ke6 { -M14/36 2.7s}
40... c1=Q { +M13/36 4.3s}  41. Kd7 { -M12/39 2.7s}  41... Qf4 { +M11/42 3.7s}
42. Ke7 { -M10/63 3.5s}  42... Qc7+ { +M9/74 3.4s}  43. Ke6 { -M8/120 0.37s}
43... Qh7 { +M7/120 0.31s}  44. Ke5 { -M6/120 0.049s}  44... Qg6 { +M5/120
0.032s}  45. Kf4 { -M4/120 0.005s}  45... Qg5+ { +M3/120 0.005s}  46. Kf3 {
-M2/1 0.001s}  46... Qg3# { Stockfish 261014 64-Stockfish 261014 64 2015.12.28}
 ) ( 10. Bf1+ { -3.77/25 23s}  10... Kc3 { +3.96/28 8.4s}  11. Be2 { -2.77/25
7.0s}  11... Qb7+ { +4.11/27 21s}  12. Kf2 { -3.58/25 15s}  12... Qf7+ {
+4.58/27 57s}  13. Kg1 { -3.65/28 17s}  13... Qg7+ { +4.81/25 10s}  14. Kf2 {
-4.29/28 63s}  14... Qf6+ { +4.81/26 8.1s}  15. Kg1 { -5.62/27 8.2s}  15...
Qg5+ { +4.81/26 5.3s}  16. Kf2 { -7.01/28 19s}  16... Kd2 { +4.59/25 31s}  17.
Qh1 { -4.68/22 15s}  17... Qf4+ { +4.59/25 4.9s}  18. Bf3 { -5.41/23 13s}
18... Kxd3 { +4.65/25 4.9s}  19. Qb1+ { -4.70/23 5.6s}  19... Nc2 { +5.29/23
6.8s}  20. Qb6 { -5.13/22 18s}  20... Kc3 { +10.06/23 5.0s}  21. Qa5+ {
-11.58/23 15s}  21... Kb2 { +23.63/21 9.5s}  22. Qb6+ { -16.12/25 16s}  22...
Kc1 { +49.17/29 11s}  23. Qb3 { -17.10/27 25s}  23... Qh2+ { +52.34/34 4.8s}
24. Bg2 { -52.38/34 7.3s}  24... d3 { +52.34/34 4.8s}  25. Qxd3 { -59.72/34
9.6s}  25... Qxg2+ { +M43/38 4.8s}  26. Kxg2 { -59.72/1 0.001s}  26... Ne1+ {
+M37/38 4.8s}  27. Kf2 { -M36/39 12s}  27... Nxd3+ { +M35/37 4.8s}  28. Kg3 {
-M34/37 11s}  28... Ne5 { +M33/36 8.7s}  29. Kf4 { -M32/36 9.0s}  29... Nxc4 {
+M31/35 4.7s}  30. Ke4 { -M30/35 7.2s}  30... Nb2 { +M29/34 7.0s}  31. Ke3 {
-M24/34 9.7s}  31... c4 { +M25/34 7.3s}  32. Kf4 { -M22/33 6.4s}  32... Kd2 {
+M23/32 4.5s}  33. Kg5 { -M20/33 5.6s}  33... c3 { +M19/32 8.6s}  34. Kf4 {
-M18/31 3.8s}  34... c2 { +M17/31 4.3s}  35. Ke5 { -M16/31 6.3s}  35... Nd3+ {
+M15/30 6.5s}  36. Ke6 { -M14/34 5.8s}  36... c1=Q { +M13/33 4.1s}  37. Ke7 {
-M12/39 3.6s}  37... Qc6 { +M11/39 4.6s}  38. Kf7 { -M10/72 3.5s}  38... Ne5+ {
+M9/78 4.1s}  39. Ke7 { -M8/120 0.36s}  39... Qb6 { +M7/120 0.39s}  40. Kf8 {
-M6/120 0.034s}  40... Qd6+ { +M5/120 0.018s}  41. Kg8 { -M4/120 0.007s}  41...
Qg6+ { +M3/120 0.007s}  42. Kh8 { -M2/120 0.003s}  42... Nf7# { Stockfish
261014 64-Stockfish 261014 64 2015.12.28}  ) ( 10. Bf1+ { -3.70/24 11s}  10...
Kc3 { +3.65/29 7.6s}  11. Be2 { -3.21/24 7.2s}  11... Qb7+ { +3.93/28 20s}  12.
Kf2 { -3.54/24 20s}  12... Qf7+ { +4.26/28 26s}  13. Kg1 { -3.81/26 12s}  13...
Qg7+ { +4.26/28 6.9s}  14. Kf2 { -3.68/26 7.1s}  14... Qf6+ { +4.51/24 12s}
15. Kg1 { -3.93/22 12s}  15... Qg5+ { +4.89/26 12s}  16. Kf2 { -4.41/23 20s}
16... Nf5 { +5.10/26 6.8s}  17. Qh3 { -5.61/24 15s}  17... Kd2 { +6.68/24 16s}
18. Bg4 { -6.68/25 18s}  18... Qf4+ { +6.01/23 13s}  19. Kg1 { -5.68/25 6.6s}
19... Ne3 { +5.99/24 8.9s}  20. Bf3 { -6.95/25 12s}  20... Kxd3 { +6.86/23
9.7s}  21. Bc6 { -8.54/27 43s}  21... Kxc4 { +7.84/24 9.1s}  22. Qc8 { -8.22/24
15s}  22... Kd3 { +9.20/25 10s}  23. Qb7 { -8.96/25 12s}  23... Qg3+ { +9.26/24
9.0s}  24. Kh1 { -8.54/27 5.7s}  24... Qe1+ { +9.51/24 10s}  25. Kh2 { -8.54/1
0.001s}  25... c4 { +11.72/25 30s}  26. Bf3 { -8.05/27 5.8s}  26... Qh4+ {
+13.43/24 8.1s}  27. Kg1 { -7.84/1 0.002s}  27... c3 { +17.34/25 14s}  28. Qb1+
{ -14.91/23 11s}  28... Kd2 { +32.61/27 28s}  29. Qa2+ { -20.49/25 11s}  29...
Nc2 { +22.64/27 14s}  30. Bc6 { -49.10/27 25s}  30... Qg5+ { +48.89/28 11s}
31. Kf2 { -52.38/29 31s}  31... Qf6+ { +49.06/30 4.9s}  32. Bf3 { -52.25/31
4.6s}  32... Qh4+ { +M47/29 41s}  33. Kg2 { -52.30/30 21s}  33... d3 {
+29.63/29 35s}  34. Bd5 { -39.71/21 6.0s}  34... Kc1 { +M57/28 3.3s}  35. Bb3 {
-52.34/27 8.8s}  35... Ne1+ { +M59/27 11s}  36. Kf1 { -M58/27 8.3s}  36... Qh1+
{ +M61/29 3.3s}  37. Kf2 { -M56/1 0.002s}  37... Qg2+ { +M27/28 18s}  38. Ke3 {
-M48/31 3.8s}  38... Qxa2 { +M25/28 2.6s}  39. Bxa2 { -M26/29 6.5s}  39... d2 {
+M25/27 2.6s}  40. Bb3 { -M24/29 5.5s}  40... c2 { +M21/27 2.5s}  41. Bxc2 {
-M20/27 6.8s}  41... Kxc2 { +M19/28 2.7s}  42. Kd4 { -M16/28 6.7s}  42... d1=Q+
{ +M17/25 2.4s}  43. Ke5 { -M14/33 7.2s}  43... Qd7 { +M13/30 2.7s}  44. Kf6 {
-M12/41 4.2s}  44... Nf3 { +M11/36 2.3s}  45. Kg6 { -M10/1 0.001s}  45... Qe6+
{ +M9/61 2.3s}  46. Kh7 { -M8/120 0.57s}  46... Ne5 { +M7/120 0.36s}  47. Kh8 {
-M6/120 0.012s}  47... Qf6+ { +M5/120 0.008s}  48. Kh7 { -M4/120 0.002s}  48...
Qg6+ { +M3/120 0.003s}  49. Kh8 { -M2/1 0s}  49... Nf7# { Stockfish 261014
64-Stockfish 261014 64 2015.12.28}  ) ( 10. Qf2 { -3.63/25 22s}  10... Qb7+ {
+13.97/28 11s}  11. Kg3 { -8.02/29 18s}  11... Qg7+ { +10.42/31 63s}  12. Kh3 {
-39.78/35 27s}  12... Qg2+ { +44.66/33 8.2s}  13. Qxg2 { -48.94/38 9.3s}  13...
Nxg2 { +52.34/37 8.5s}  14. Bf3 { -57.12/38 14s}  14... Ne1 { +58.68/40 17s}
15. Be4 { -58.81/39 34s}  15... Nxd3 { +63.24/39 17s}  16. Kg3 { -33.37/38 57s}
 16... Ke3 { +73.47/39 19s}  17. Bf5 { -59.58/32 7.7s}  17... Ne5 { +73.33/38
50s}  18. Kh4 { -M44/36 19s}  18... d3 { +M45/33 7.7s}  19. Kg5 { -M38/36 8.9s}
 19... d2 { +M43/35 4.7s}  20. Bc2 { -M36/35 6.9s}  20... Nxc4 { +M35/36 4.7s}
21. Kf5 { -M34/35 7.2s}  21... Kd4 { +M31/36 5.0s}  22. Kf4 { -M30/36 8.8s}
22... Ne3 { +M29/37 7.2s}  23. Ba4 { -M28/36 5.1s}  23... d1=Q { +M27/37 4.7s}
24. Bxd1 { -M26/36 5.0s}  24... Nxd1 { +M25/35 4.7s}  25. Kf3 { -M22/37 8.0s}
25... Kd3 { +M23/35 5.4s}  26. Kg2 { -M20/38 7.6s}  26... c4 { +M19/36 4.7s}
27. Kh2 { -M18/40 6.6s}  27... c3 { +M17/39 4.7s}  28. Kg3 { -M16/42 4.9s}
28... c2 { +M15/39 4.7s}  29. Kg4 { -M14/42 7.1s}  29... Ne3+ { +M13/43 4.9s}
30. Kg5 { -M12/55 6.6s}  30... c1=Q { +M11/55 4.8s}  31. Kg6 { -M10/84 4.7s}
31... Qc6+ { +M9/111 4.7s}  32. Kg7 { -M8/120 0.87s}  32... Nf5+ { +M7/120
0.070s}  33. Kf7 { -M6/120 0.004s}  33... Kd4 { +M5/120 0.009s}  34. Kg8 {
-M4/120 0.005s}  34... Qf6 { +M3/120 0.004s}  35. Kh7 { -M2/1 0.001s}  35...
Qg7# { Stockfish 261014 64-Stockfish 261014 64 2015.12.28}  ) 10... Qb6 {
+3.62/23 11s}  11. Qh8 { -3.81/24 39s}  ( 11. Bf3 { -4.08/25 59s}  11... Kxd3 {
+3.94/21 8.7s}  12. Qg1 { -4.12/21 23s}  12... Qb2+ { +4.08/20 11s}  13. Kg3 {
-4.43/21 14s}  13... Nxc4 { +4.41/21 26s}  14. Bh5 { -4.24/21 29s}  14... Ne3 {
+4.63/21 12s}  15. Bg6+ { -4.65/20 14s}  15... Kc3 { +4.75/22 30s}  16. Kf3 {
-4.94/23 44s}  16... c4 { +5.45/22 7.8s}  17. Qe1+ { -4.99/21 13s}  17... Kb3 {
+6.49/23 5.6s}  18. Ke4 { -5.93/23 16s}  18... c3 { +6.97/23 5.6s}  19. Kd3 {
-7.31/22 12s}  19... Ka3 { +7.49/24 9.0s}  20. Qh1 { -8.99/22 20s}  20... Qd2+
{ +11.19/20 7.8s}  21. Ke4 { -8.99/1 0s}  21... c2 { +11.39/22 13s}  22. Qa1+ {
-13.00/18 5.3s}  22... Kb4 { +12.91/23 23s}  23. Qb2+ { -8.88/18 6.0s}  23...
Kc5 { +13.14/24 30s}  24. Qa3+ { -10.71/20 9.4s}  24... Qb4 { +14.12/25 40s}
25. Qc1 { -11.76/22 13s}  25... Qc3 { +14.09/25 6.1s}  26. Kf3 { -17.11/23 19s}
 26... Nf5+ { +14.15/25 35s}  27. Kg4 { -19.91/23 26s}  27... Qd3 { +18.03/21
7.0s}  28. Qf4 { -19.98/19 5.5s}  28... Qd1+ { +10.94/20 5.0s}  29. Kxf5 {
-20.46/19 8.4s}  29... c1=Q { +11.15/21 3.2s}  30. Qc7+ { -16.23/20 13s}  30...
Kb4 { +18.18/18 4.9s}  31. Qb7+ { -16.35/21 18s}  31... Kc3 { +23.17/20 10s}
32. Qc7+ { -13.56/15 2.3s}  32... Kb2 { +39.71/21 4.3s}  33. Qb6+ { -11.17/15
4.9s}  33... Ka3 { +28.70/22 9.8s}  34. Qd6+ { -21.64/18 9.3s}  34... Ka2 {
+18.53/22 8.0s}  35. Bf7+ { -20.06/20 1.4s}  35... Kb1 { +49.10/25 2.5s}  36.
Qb8+ { -49.02/21 3.4s}  36... Qb2 { +M67/25 8.9s}  37. Qf4 { -49.10/23 2.0s}
37... Qdc2+ { +M65/24 2.3s}  38. Kg4 { -49.62/25 6.1s}  38... Qb7 { +M21/24
11s}  39. Kh4 { -M22/19 1.7s}  39... Qh7+ { +M19/25 2.1s}  40. Bh5 { -M18/24
1.1s}  40... Qhe7+ { +M17/28 2.3s}  41. Kg3 { -M16/27 1.5s}  41... Qe1+ {
+M15/31 2.0s}  42. Qf2 { -M14/31 1.0s}  42... Qg7+ { +M13/34 2.2s}  43. Bg4 {
-M12/37 0.99s}  43... Qxf2+ { +M11/43 2.1s}  44. Kxf2 { -M10/81 0.97s}  44...
Qxg4 { +M9/100 1.9s}  45. Kf1 { -M8/120 0.11s}  45... d3 { +M7/120 0.065s}  46.
Kf2 { -M6/120 0.003s}  46... d2 { +M5/120 0.005s}  47. Ke3 { -M4/120 0.005s}
47... d1=Q { +M3/120 0.005s}  48. Kf2 { -M2/1 0s}  48... Qgg1# { Stockfish
261014 64-Stockfish 261014 64 2015.12.28}  ) ( 11. Qf4 { -3.84/25 32s}  11...
Qg6 { +4.39/25 34s}  12. Qf3 { -4.06/24 11s}  12... Qg5 { +4.56/25 24s}  13.
Qh1 { -4.46/24 24s}  13... Qf4+ { +4.89/22 5.7s}  14. Bf3 { -4.46/24 6.3s}
14... Kxd3 { +5.50/22 11s}  15. Qb1+ { -6.26/23 38s}  15... Nc2 { +5.89/23
8.6s}  16. Qb2 { -6.49/25 22s}  16... Qh4+ { +8.75/24 5.6s}  17. Kg1 { -8.89/25
13s}  17... Qg3+ { +10.73/25 7.8s}  18. Bg2 { -10.51/27 12s}  18... Kd2 {
+10.39/26 10s}  19. Kh1 { -7.77/26 5.5s}  19... Qh4+ { +12.27/25 15s}  20. Kg1
{ -11.33/23 8.0s}  20... d3 { +12.24/26 16s}  21. Bb7 { -16.35/28 50s}  21...
Qxc4 { +17.62/26 11s}  22. Kg2 { -16.58/25 13s}  22... Qd4 { +52.18/28 7.3s}
23. Qb1 { -31.53/27 31s}  23... Ne3+ { +M25/28 7.1s}  24. Kh1 { -M24/27 7.9s}
24... Qh4+ { +M21/31 6.2s}  25. Kg1 { -M22/1 0.001s}  25... Qg3+ { +M19/36
5.4s}  26. Kh1 { -M18/36 5.8s}  26... Ke2 { +M17/38 5.1s}  27. Qc1 { -M16/38
4.0s}  27... Qh4+ { +M15/41 5.5s}  28. Kg1 { -M16/1 0.001s}  28... Qf2+ {
+M13/49 6.0s}  29. Kh1 { -M14/1 0s}  29... d2 { +M11/70 5.2s}  30. Ba6+ {
-M10/81 5.7s}  30... Kf3 { +M9/120 0.47s}  31. Be2+ { -M8/120 0.40s}  31...
Qxe2 { +M7/120 0.007s}  32. Qg1 { -M6/120 0.005s}  32... d1=Q { +M5/120 0.005s}
 33. Qxd1 { -M4/120 0.002s}  33... Nxd1 { +M3/120 0.003s}  34. Kg1 { -M2/1 0s}
34... Qg2# { Stockfish 261014 64-Stockfish 261014 64 2015.12.28}  ) 11... Qd6 {
+3.95/24 20s}  12. Qh4 { -4.12/23 28s}  12... Qg6 { +4.53/24 61s}  13. Bf3 {
-4.00/23 6.4s}  13... Qxd3 { +4.83/24 54s}  14. Qh1 { -3.97/19 8.7s}  14... Nc2
{ +5.34/22 8.3s}  15. Qd1+ { -5.43/23 37s}  15... Kc3 { +5.34/1 0.001s}  16.
Qb1 { -10.45/27 29s}  16... Qxc4 { +5.94/21 7.7s}  17. Bg4 { -7.25/23 40s}
17... d3 { +6.90/21 5.2s}  18. Kg3 { -6.25/23 5.1s}  18... Qd4 { +7.42/22 10s}
19. Qa2 { -8.84/22 27s}  19... c4 { +8.15/24 17s}  20. Qa6 { -12.20/23 39s}
20... d2 { +15.03/23 33s}  21. Qa8 { -12.86/24 20s}  21... Kb2 { +11.22/20
7.5s}  22. Qb7+ { -14.57/23 12s}  22... Kc1 { +13.31/22 10s}  23. Qa8 {
-14.50/24 6.0s}  23... c3 { +15.70/24 18s}  24. Bf3 { -13.50/24 5.2s}  24...
Kb2 { +52.18/18 5.8s}  25. Kh3 { -52.11/19 6.0s}  25... Nb4 { +M47/22 13s}  26.
Qa4 { -M30/21 11s}  26... c2 { +M17/23 5.3s}  27. Qxc2+ { -M16/23 4.2s}  27...
Kxc2 { +M15/33 3.9s}  28. Bg4 { -M14/33 4.9s}  28... d1=Q { +M13/33 4.3s}  29.
Bxd1+ { -M12/53 3.6s}  29... Kxd1 { +M11/57 4.0s}  30. Kg2 { -M10/113 3.5s}
30... Qg4+ { +M9/120 3.7s}  31. Kf1 { -M8/120 0.12s}  31... Qh3+ { +M7/120
0.013s}  32. Kg1 { -M6/120 0.021s}  32... Nc2 { +M5/120 0.005s}  33. Kf2 {
-52.38/1 0s}  33... Ne3 { +M3/120 0.002s}  34. Kg1 { -M2/1 0s}  34... Qg2# {
+M1/120 0.002s, Black mates}   0-1

We can strongly(but not absolutely) believe that Black wins in this position.


What is the meaning of this chess opening theory table? On this example chess opening theory table, what does "Σ%" and the number before it mean?

The two figures in the “Σ%” column are the number of games referenced in the database (so “Σ” should be understood in its mathematical meaning, “total” or “sum”) and the percentage of games won by White.