86
votes
Accepted
Is it sportsmanlike to waste opponents' time by giving check at the end of the game?
That only works in blitz time controls with no increment. If you accept games with no increment you are basically agreeing that flagging is part of the game and sportsmanlike. If you personally find ...
50
votes
Is it sportsmanlike to waste opponents' time by giving check at the end of the game?
In blitz, time is a major factor in the game, and it is fine to try and win on time.
If you used too much time, and your opponent thinks he can flag you, there is nothing wrong with that. It is part ...
50
votes
Must one say "queen check" before capturing a queen?
The official FIDE laws of chess do not know about a queen check. Announcing a "queen check“ might even be considered a case of "to distract or annoy the opponent“ (11.5). Even announcing a &...
42
votes
Is it sportsmanlike to waste opponents' time by giving check at the end of the game?
Time is a resource in blitz chess, as much as or even more so than material. If it isn't unsportsmanlike to capture your opponent's material, how is it unsportsmanlike to capture their time?
In ...
39
votes
Can a player in check win, by checkmating the opponent, while not getting themselves out of check?
For this kind of question, if you have doubts, just play chess with the goal of capturing the enemy king. The first player to capture the enemy king wins. This isn't the official rule, but it's ...
37
votes
Accepted
When capturing en passant, is a position possible such that there is a pin over the square of the taken pawn, rather than the taking pawn?
Really interesting question. I think the following shows that such a situation is sort of possible, depending on how you define the pin.
[StartFlipped "0"]
[FEN "7k/4p3/8/2KP3r/8/8/8/8 ...
37
votes
Can a player in check win, by checkmating the opponent, while not getting themselves out of check?
According the FIDE LAWS of CHESS:
3.9.2 No piece can be moved that will either expose the king of the same colour to check or leave that king in check.
So as @djnavas points out, if you are in check ...
31
votes
Must one say "queen check" before capturing a queen?
No.
Some people think it is polite to say 'gardez' to alert a player that the Q can be taken.
But no rule says you have to say check nor gardez and in serious games with good players it is not done.
...
29
votes
Is it sportsmanlike to waste opponents' time by giving check at the end of the game?
waste their time
If it's clear that they are able to win within the time they have left, this could be considered bad sportsmanship. However, in those situations the number of remaining checks is ...
25
votes
Accepted
Moving into check for a draw as black, why is it illegal? Comparison to Racing Kings
Imagine a variation of chess without the rules about check and checkmate, where a player wins simply when he captures his opponent's king. In this variation, Kxd5 loses the game to exd5.
Turns out, ...
22
votes
Accepted
Is it true that at any time only one piece can put king in check?
Double check is a fine tactic. An example would be a bishop lined up on the same diagonal as the king with a rook or knight in the way blocking the check. The rook or knight moves giving check to the ...
22
votes
Accepted
Is triple check possible?
Triple check is impossible, unless you want to count an x-ray attack as the third check. A queen and rook attacking on the same file is normally thought to be one check.
21
votes
Is triple check possible?
To look at this systematically, let's say white is attempting to triple-check black.
At the start of white's move, black's king is not in check. So we have to go from zero checks to three checks.
When ...
21
votes
Accepted
Why did white sacrifice knight in this Nimzowitsch's 1905 game?
White has a mating threat (Qxh7 Kxh7 Rh6#) that he couldn't execute because he was under check. On the next move Black will remove the mating threat with 1...Qxg6 or with a knight move, most probably ...
20
votes
Why is offering draw not recorded but giving a check recorded?
Both recording checks and draw offers are personal preference, and neither is required in your notation.
I actually do record both checks as "+" or "++", and draw offers as "(d)". I know I am not the ...
20
votes
Accepted
Why is offering draw not recorded but giving a check recorded?
According to the FIDE Laws of Chess:
Appendix C. Algebraic notation
C.12 The offer of a draw shall be marked as (=)
As with a number of the laws regarding recording of the moves this is not ...
18
votes
Moving into check for a draw as black, why is it illegal? Comparison to Racing Kings
Those are just the rules of the game. You could absolutely try to make the case that moving into check in such a situation should be legal, but playing by those rules wouldn't be chess anymore (it ...
17
votes
Moving into check for a draw as black, why is it illegal? Comparison to Racing Kings
I will answer from a different perspective: why Racing Kings (RK) has a rule to allow black a chance to draw, and why the same logic doesn't apply to chess.
What is Racing Kings (RK)?
Background for ...
16
votes
Can a player in check win, by checkmating the opponent, while not getting themselves out of check?
No, this is not legal. The fact that the black king is still in check from the white rook overrides every other consideration. It doesn't matter that (were it not for the white rook) Black's move ...
15
votes
Accepted
Is it ethical to force a draw via perpetual check?
There is a rules in chess called Threefold repetition rule. This rule states that you can claim a draw if you are about to repeat the the position for a third time. This subsumes a situation called ...
14
votes
How do computers play three-check chess?
I have been working on the aforementioned code of Stockfish for three-check chess, so I will try to summarize the most important evaluation changes (in terms of Elo gain) we made compared to standard ...
14
votes
Must one say "queen check" before capturing a queen?
The important part is that you and your friend agree on what to say and when. If you both agree that queen check (or gardez) is a nice thing to say, then go ahead and say it.
I suggest taking the time ...
13
votes
Accepted
How do computers play three-check chess?
https://github.com/ddugovic/Stockfish
Very active development, this is the Stockfish version used by lichess.
What you need to do is search this macro:
#ifdef THREECHECK
Evaluation function:
...
13
votes
Can a king be checked with another king when checking square is protected by the side which gives the check?
Hi David and welcome to chess.stackexchange.com. This is a common question.
It's illegal to move a king into check, or to leave it in check. This includes moving a king adjacent to the opposing king....
12
votes
Accepted
What is the theoretical limit for the number of consecutive checks?
37 is the record so far without promoted pieces.
[Title "Giuseppe Ponzetto, Torre i Cavallo 1993, 37 Consecutive Checks"]
[FEN "4r1Q1/B2nr3/5b2/8/4p3/4KbNq/ppppppp1/RR3Nkn w - - 0 1&...
12
votes
Accepted
Checkless Chess
Your "checkless" chess AI would run into problems with the stalemate rule. It would consider the poaition with white king on a6, white pawn a7, black king a8, a win for White because wherever Black ...
12
votes
Accepted
Series of illegal moves in check
The answer depends on whether or not the games are being recorded. The way this is elliptically referenced in the FIDE Laws of Chess is that a distinction is made between, on the one hand, standard ...
11
votes
Accepted
Why is the definition of check not circular?
A move can be illegal because the opponent could "take" the king. This "taking the king" move does not need to be "legal". See Can a piece pinned to my king put the opponent's king in check? and ...
11
votes
Is triple check possible?
Triple check is possible in the chess variant known as Cylinder Chess. In this position, 1.Ra8 discovers check from the queen and bishop, so it's triple or maybe quadruple check, depending on whether ...
Only top scored, non community-wiki answers of a minimum length are eligible
Related Tags
check × 90rules × 34
checkmate × 27
kings × 14
problems × 7
chess-variants × 7
illegal-move × 7
perpetual × 7
draw × 6
engines × 5
analysis × 5
programming × 4
records × 4
captures × 4
pins × 4
forced-move × 4
endgame × 3
puzzles × 3
castling × 3
etiquette × 3
stalemate × 3
winning × 3
double-check × 3
theory × 2
tactics × 2