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Give a legal position which is "dead" but would take (assuming the §5.2.2 about dead positions wouldn't exist) maximally long to play out until an automatic draw by fivefold, 75 moves or statemate results.

[FEN "5b1k/4p1pB/4PbP1/8/8/8/8/7K w KQkq - 0 1"]

This is a non-example (in a help-game e7 can be taken eventually) so the obvious idea adding more bishops doesn't work!

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    How is this a legal position?
    – Brian Towers
    Feb 1 at 11:29
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    @BrianTowers It is a legal position, but unlikely to occur in a real game, as both players would have to cooperate to reach it. Black has never moved his bishop from the starting square and promoted a pawn to another bishop of the same colour (a or c-pawn). Whites bishop got into h7 after Blacks King went to h8 and after that, Black shuffled his bishop while White advanced his pawns to e6 and g6.
    – Hauptideal
    Feb 1 at 13:07
  • I like the term "death certificate"
    – Laska
    Apr 11 at 8:45

1 Answer 1

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Here is such a position.

[FEN "1k6/p1p1p1p1/P1P1P1P1/8/8/8/PKP1P1P1/8 b - - 0 1"] 
[startlfipped ""] 

With Black to move, no side can make any progress. White still has plenty of pawn moves to make to reset the 75 move counter. It's a legal position as well.

Interestingly, this is a position that humans understand better than engines! It's a draw, even if Stockfish insists it's +7.

EDIT:

As pointed out in the comments, adding 4 black pawns that White can take adds another 12 resets to the 50 (75 if unclaimed) move counter.

Also, a wBh7 that cannot escape and will eventually be taken would add yet one more reset but this is not possible since this bishop never could escape f1 to get there.

[FEN "kR6/p1p1p1p1/P1P1P1P1/p1p1p1p1/8/8/PKP1P1P1/8 b - - 0 1"] 
[startlfipped ""] 
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    I guess that's a record - a useless bishop only gives +50 moves once, when it is captured. The pawns give 4x50. Feb 1 at 20:22
  • No, they give much more than that. They give 75 moves (50 if claimed) each time they are moved, and there are 12 pawn moves. Which would amount to hundreds of moves in any case.
    – Hauptideal
    Feb 1 at 21:00
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    Note added in browsing through old MatPlusForum threads: Add black Pg5 Pe5 Pc5 Pa5. Still dead, but White can capture the straddlers and then run own pawns. (2b+1capture+3w)*4*50 doubles the record :-) matplus.net/… I even participated in that thread, shame on me :-) Feb 7 at 17:08
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    that's right, very good idea! I also thought about whether Black should start on a8, with the only move to capture a piece on b8 in order to make sure the move counter is reset. I will edit the answer accordingly.
    – Hauptideal
    Feb 8 at 0:00
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    @Hauptideal: going through old MatPlusForum posts again, I had an idea: +wBh7! It can't get out and adds another 50 moves when captured. Apr 6 at 8:06

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