In zugzwang, the usual idea is to limit the number of moves that the opponent can make. But they can also have many moves in certain scenarios. What is the highest amount number of moves by the losing side in a zugzwang position, with and without promoted pieces allowed?
2 Answers
The following are full-point zugzwangs, so both sides are losing if either moved!
[Title "Noam Elkies. EG 128, Apr 1998, p.53, 10967 (v)"]
[StartFlipped "0"]
[fen "8/8/k7/8/K7/RNbn4/B7/1R6 w - - 0 1"]
1. Rc1 Nb2#
White: 8 with wRb1, 6 with N = 14. Black: 11 with B, 8 with N, 3 with K = 22. Total-36.
[Title "Noam Elkies. EG 128, Apr 1998, p.53, 10967 (text, v)"]
[StartFlipped "0"]
[fen "8/8/8/k1n5/8/K7/RRb5/QBb1n3 w - - 0 1"]
1. Bxc2 Nxc2#
White: 1 with B = 1. Black: 9 with Bc2, 6 with Bc1, 8 with Nc5, 3 with Ne1, 1 with K = 27. Total-28.
If you allow promoted pieces in the diagram: The following is a half-point zugzwang.
[Title "half-point zugzwang: WTM draws. BTM loses in 14"]
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[fen "3q4/8/4q3/2Q5/k7/8/8/2K4Q b - - 0 1"]
1... Qg5+ 2. Qxg5! Qc4+ 3. Kd2
It is a draw if it is white to move. Meanwhile, if it is Black to move, they lose in 14 moves. Black has 25 moves with Qe6, 21 moves with Qd8, and 1 with Ka4, for a grand total of 47.