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What is the zugzwang? I have read this term in chess book but the term not much clear to me. Anyone know to to use this and what are the advantage of this?

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    I don't see any reason for downvoting this question whatsoever. It is totally legitimate, and it is not at all difficult to understand what the poster is asking for.
    – Scounged
    Commented Apr 6, 2018 at 10:59
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    If you hover over the "down vote" button it says "This question does not show any research effort, it is unclear or not useful". If you had made the effort to use Google or even search this site then you would have had your answer. Your question shows zero research effort and is useless. Hence the down vote from me.
    – Brian Towers
    Commented Apr 6, 2018 at 11:00
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    Note that all of these user's questions show little research effort or none at all.
    – Glorfindel
    Commented Apr 6, 2018 at 11:01
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    And this user never responds properly to any of the nice answers he has received
    – Laska
    Commented Apr 6, 2018 at 11:09
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    @IanBush because we're not trying to duplicate Wikipedia.
    – Glorfindel
    Commented Apr 6, 2018 at 20:37

4 Answers 4

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Here are some zugzwang positions which have been shown in answers to earlier threads:

4k3/8/3P1P/8/8/3p1p2/8/4K3 w - - 0 1

First to move loses (posted by GloriaVictis at this question on symmetrical zugzwangs).

8/8/8/3pK3/2kP4/8/8/8 w - - 0 1

The "trebuchet" (posted by Evargalo in the same thread).

3k4/3P4/4K3/8/8/8/8/8 w - - 0 1

Posted by Simon Louchart in this thread.

Here is a Q v RPP zugzwang: White to move can't win, but Black to move loses:

[Title "KQkrpp position from John Beasley's collection of zugzwang positions"]
[StartFlipped "0"]
[fen "kr6/1pK5/pQ6/8/8/8/8/8 b - - 0 1"]

1... Rc8 2. Kxc8 a5 3. Qxb7#

Seeing as a KBP v K position has been posted in another answer, here's an example of such a position which really is a zugzwang: White to move can't win, but Black to move loses:

[Title "KBPk position from John Beasley's collection of zugzwang positions"]
[StartFlipped "0"]
[fen "kB6/8/1PK5/8/8/8/8/8 b - - 0 1"]

1... Kxb8 2. b7 Ka7 3. Kc7 Ka6 4. b8=Q Ka5 5. Qb3 Ka6 6. Qa4#
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  • I guess John Beasley must have observed that the last position cannot legally arise with Black to move . . . Commented Dec 2, 2021 at 5:54
  • @NoamD.Elkies Have I missed anything? White could've just captured something, or else (working backwards from the diagram) Kd5-c6 Kb7-a8.
    – Rosie F
    Commented Dec 2, 2021 at 7:57
  • Sorry I goofed: it can't legally arise with White to move, i.e. with Black having moved last. (Ka7-a8 or Ka7xa8 would require an impossible double check.) Commented Dec 2, 2021 at 15:51
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Zugzwang is a situation where every single one of a player's moves loses, but if he didn't have to move then he'd be fine.

Consider this position:

White King on d5, White pawn on e4, Black King on f4, Black pawn on e5.

Whoever's move it is loses. If it's White's move then he must move his King away, and Black takes the e4-pawn. White does not want to move, but he's not allowed to skip a turn.

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Zugzwang, compulsion-to-move, is where a player is forced to disadvantage their position, or obscure their strategy, tactics, or attacks by moving.

Example #1

 8/8/8/3pK3/2kP4/8/8/8 w - - 0 1

In this position each King aims to protect its pawn, but if it's white to play, white is forced to move away since the pawn's movement is restricted and c6 is guarded by the pawn. Checkmate in 15 (WTM)

Example #2

3k4/3P2K1/8/8/8/7B/8/8 b - - 0 1

This is a more active puzzle, but a checkmate in 9 for white (BTM)

King c7

1... Kc7 2. Bf5 Kb6 3. d8=Q+ Kc5 4. Qd3 Kb4 5. Qd4+ Kb3 6. Kf6 Ka3 7. Qc3+ Ka2 8. Qb4 Ka1 9. Qb1#

King e7

1... Ke7 2. Bf5 Kd6 3. Kf6 Kc5 4. d8=Q Kc4 5. Ke7 Kc3 6. Qd3+ Kb2 7. Qc2+ Ka3 8. Qc3+ Ka2 9. Qb4 Ka1 10. Qb1#

Black is forced to move the king from d8 with e7 and c7 both leading to checkmates in perfect checkmates in 9

Example 3

5Kbk/6pp/6P1/8/8/8/8/7R w - - 0 1

White to move. Mate in 2. This one uses rh6 to lock the h7 pawn leaving only the bishop able to move, which forces it to abandon it's defense of the h7 pawn leading to rh7 checkmate.

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    Your 1st example isn't really zugzwang, because White wins with or without the move. In your 2nd, as you say, White wins with the move but it's a draw with BTM. Every White move is check so in what sense is this zugzwang?
    – Rosie F
    Commented Apr 6, 2018 at 7:22
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    The 1st example would be better with the black king on c5, when it would be mutual zugzwang (the one whose move it is will lose the pawn and game). I don't see any zugzwang in your second example. Commented Apr 6, 2018 at 8:41
  • I fixed the 1st to be mutual, and the second fixed with black to move away from restricting pawn. Sorry for the inconvenience Commented Apr 6, 2018 at 8:44
  • I still don't see how your new second example (KBPk) is zugzwang. WTM wins in 8 or 9 whether Black's king is on c7, d8 or e7.
    – Rosie F
    Commented Apr 6, 2018 at 9:29
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    @RosieF The new second example is zugwang. If black was allowed not to make moves (to pass), there is no way white can promote the pawn because black would just leave the king on d8 (and white has no checks to make black move the king. Commented Apr 6, 2018 at 10:07
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An interesting point: without zugzwang, you could not win with only a rook (assuming no other pieces than kings) - you would need two bishops at least. That just shows how much is this "rule" (obligation to move) important.

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  • If the rules allowed to give up a move, you could not force KR-K mate.
    – Ferazhu
    Commented Dec 1, 2021 at 21:48

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