Two moves per go

Two moves per go

Posers and Puzzles

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Krackpot Kibitzer

Right behind you...

Joined
27 Apr 02
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16879
19 Apr 05

Imagine a variant of standard chess where each player can move the same piece twice on every go.

You might imagine that White, in virtue of starting off, would have an advantage in this situation. And indeed he does!

Question:

Suppose Black had the choice of removing just one White piece by way of compensation. What piece should he remove?

P

Joined
30 Dec 04
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19 Apr 05

Errrrr.... the Queen???

P
Bananarama

False berry

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19 Apr 05
1 edit

Originally posted by Pawnokeyhole
Imagine a variant of standard chess where each player can move the same piece twice on every go.

You might imagine that White, in virtue of starting off, would have an advantage in this situation. And indeed he does!

Question:
...[text shortened]... e White piece by way of compensation. What piece should he remove?
The King! 😀

But if you can't do that, then we have the following choices: pawn, knight, bishop, rook, queen.

I don't think there's much value in removing a pawn. Removing either a bishop or a rook wouldn't be as effective as removing the queen, because the queen is basically a bishop and a rook combined. Removing the opponent's queen is always a good thing, so queen would be a good choice.

Knights are notoriously tricky to maneuver into place, but when they are in place they exert enormous pressure. They don't require line-of-sight to capture, and it's possible to fork several pieces at once. They can also use their 2-move advantage on the first move by jumping over the row of pawns.

So I think either the queen or a knight would be the best choice, and strangely enough I think removing a knight would be most effective.

T

Joined
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19 Apr 05
1 edit

Originally posted by Pawnokeyhole
You might imagine that White, in virtue of starting off, would have an advantage in this situation. And indeed he does!
In fact, to offset this advantage White is usually allowed only one initial move.
http://www.chessvariants.org/multimove.dir/doublemove.html

Perhaps even more interesting is Progressive Chess.
http://www.chessvariants.org/multimove.dir/progressive.html

P

Joined
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19 Apr 05

Originally posted by PBE6
So I think either the queen or a knight would be the best choice, and strangely enough I think removing a knight would be most effective.
I did consider removing a knight, but as white would be left with one knight capable of moving twice anyway, I decided to plump for the obvious option!

TP
Leak-Proof

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19 Apr 05

Originally posted by PBE6
The King! 😀
I thought about the King too, but decided it would be really tough for Black to checkmate White if White's king wasn't on the board.

Had the question been stated slightly different, the answer would have been Black's King....😲

P
Bananarama

False berry

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19 Apr 05

Originally posted by The Plumber
I thought about the King too, but decided it would be really tough for Black to checkmate White if White's king wasn't on the board.

Had the question been stated slightly different, the answer would have been Black's King....😲
Curses! Foiled again. But I have another solution: remove the piece of the board that holds the pieces up. Let's see white's knight jump over that!

Krackpot Kibitzer

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21 Apr 05

None of you have gotten it yet!

(Yes, I know that the removing the King would *technically* win. I should have explicitly ruled out this possibility in advance!)

The correct answer is: White's Queen's Knight!

So, can you tell me why?

M

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21 Apr 05

Originally posted by Pawnokeyhole
None of you have gotten it yet!

(Yes, I know that the removing the King would *technically* win. I should have explicitly ruled out this possibility in advance!)

The correct answer is: White's Queen's Knight!

So, can you tell me why?
to avoid the pair of 'double moves': 1.Nc3-Ne4 and 2.Nd6+ NxKe8 wins?

Krackpot Kibitzer

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21 Apr 05

Originally posted by Mephisto2
to avoid the pair of 'double moves': 1.Nc3-Ne4 and 2.Nd6+ NxKe8 wins?
Nearly right!

M

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21 Apr 05

Originally posted by Pawnokeyhole
Nearly right!
1.Nc3 Nd5 (instead of Ne4; after Ne4, black could play his king to the black square e7) followed by capture next move?

Krackpot Kibitzer

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22 Apr 05

The point of the puzzle is that by checking the Black king on the first move [either by Nc3 & N-b5, or Nc3 & Ne4] White is in fact *checkmating* Black because Black can't get out of check in a single move, and Black can't legally make another move while remaining in check.

However, on reflection, the terms of the puzzle are ambiguous, as it's not clear that Black should *not* have two moves to get out of check.
If this is allowed, then the knight moves to b5 then it can still be captured by a pawn in two moves, and if it moves to e4, can still be captures by either knight or pawn in two moves.

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22 Apr 05

Originally posted by Pawnokeyhole
The point of the puzzle is that by checking the Black king on the first move [either by Nc3 & N-b5, or Nc3 & Ne4] White is in fact *checkmating* Black because Black can't get out of check in a single move, and Black can't legally make another move while remaining in check.

However, on reflection, the terms of the puzzle are ambiguous, as it's not ...[text shortened]... n two moves, and if it moves to e4, can still be captures by either knight or pawn in two moves.
There are a couple ways of dealing with this ambiguity.

1) Think like Progressive - Nb5 would not be a check. A checking move terminates the series of moves, but the checked side must get out check on its first move of the series.

2) "Double-move chess" is sometimes played without the concept of check. The goal is to capture the enemy King. In other words, the checked side would have two moves to remove a potential attacker.