12

In the chess variant Duck Chess (full rules), each player moves the shared blocking "duck" piece to any free square on their turn, taking away one or more moves for the opponent.

One immediate consequence of this is the failure of "distant defence": If there are free squares between the defender and the defended, the connection can be efficiently severed by the duck.

Example: The white queen can safely capture the rook on d3, and black can not recapture if the duck is then placed on any square d4-d7

white queen b1, black rooks d3 and d8, duck looming in the distance

This is but one way that the duck nerfs sliding pieces. Additionally:

  • Duck blocking is a common way to stop a threat. Knight attacks can not be blocked.
  • The duck can at most take away one square from a knight. For a sliding piece it can be a whole ray. (Bishops more trappable?)

Does this mean knights are relatively more valuable in duck chess than in standard chess?

3
  • 1
    A related question is to ask about the point value of pieces in duck chess :) Oct 11, 2022 at 11:04
  • 1
    @BenjaminWang I imagine that's a rather more involved question Oct 11, 2022 at 11:38
  • The arguments in the question itself seem convincing enough that yes, the knights are more valuable in duck chess. But how to reach a strong enough evidence for posting an asnwer, I don't know. Maybe one can analyse endgames to see if KNN vs K or KRN vs KR are generally winning in duck chess (they are not in chess), but even this would just be one more clue, not a proof.
    – Evargalo
    Oct 11, 2022 at 12:59

3 Answers 3

3

I have played a few duck chess games and from my personal experience, knights are much better in duck chess when compared to their strength in standard chess. The piece values change, precisely because of the reason you give in your question (i.e. the duck being able to interfere with the power of rooks and bishops).

That does not only regard interference tactics (i.e. making rooks, bishops, and queens bad defenders), but also the activity of these pieces, as their paths can be blocked.

The duck can completely block a rook on an open file, making it unable to move, thus rendering it very inactive. A rook that would dominate a position in standard chess may therefore be pretty weak in duck chess.

To cut off a rook or bishop, the duck just needs to be placed on any of the controlled squares. Contrary to that, the duck can only block one square of the knight and needs to be exactly placed on that square.

Furthermore, the duck cannot block a knight's control of a square, which makes the knight the best piece to defend other pieces, as well as a great attacker.

Knights are much better than bishops in duck chess and may very well be even better than rooks, but to get objectively reliable answers about the changed piece values, we'll likely have to wait until someone adapts the chess engines to play and evaluate duck chess.

6

Although I still need to look at many more to have a sufficient sample size, I analyzed the endgames from 200 games from top duck chess players on chess.com. I recorded the material imbalance and end result and used some statistics to find values of 1, 6.5, 3.5, 5.5, and 10 (in the order of P,N,B,R,Q). I would say these values are probably uncertain to around a point and a half or so but the trends I’m getting seem to say that the knight is more powerful than the rook.

4
  • 2
    This is a good answer. Could you expand on the statistical analysis method that you used? Nov 24, 2022 at 8:57
  • 1
    Sorry for the late response. I used excel to perform a logistic regression. Jan 10, 2023 at 2:15
  • 2
    I used a method similar to the one used in this article: sumsar.net/blog/2015/06/big-data-and-chess Jan 10, 2023 at 2:22
  • 1
    In the article, the person derived a pawn value that was a bit inflated in comparison to the other pieces. My best guess is that being up other pieces also tends to mean you are going to capture the other person’s pawns as well and so the pawn value becomes inflated. Anyway, I adjusted for this pawn inflation in my calculation by looking at the data this person got. Jan 10, 2023 at 2:26
1

Though knights are stronger in duck chess, they should not be overestimated. By attacking the knight with a pawn and blocking the square, the knight would usually move to, the knight can easily be caught in many situations.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.