h#8
8/8/8/7B/8/2Q5/3k1n2/1K6 b - - 0 1
- Kxc3 Be2 Kd2 Bf1 Ke1 Kc2 Nh3 Kd3 Kf2 Ke4 Kg1 Kf3 Kh1 Kg3 Ng1 Bg2#
pure model ideal switchback self-block nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.
KQBvkn
5 pieces.
- h#12
- longest mate
- h#8
- deepest unique
- 25
- positions at that depth
- h#8
- deepest dual
- h#3
- deepest strict dual
- 152,841,530
- positions with a helpmate
- 18,620,899
- with a unique solution
- 121,110,528
- cells in the plane
- 100,978,772 bytes
- on disk
Deepest unique problems
h#8
8/8/7n/8/8/8/1K1Q4/3k2B1 b - - 0 1
- Kxd2 Bc5 Kd3 Bf8 Ke4 Kc3 Kf5 Kd4 Kg6 Ke5 Kh7 Kf6 Kh8 Kg6 Ng8 Bg7#
pure model ideal self-block nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.
h#8
8/8/8/8/3k4/2Q5/5nB1/2K5 b - - 0 1
- Kxc3 Kb1 Kd2 Bf1 Ke1 Kc2 Nh3 Kd3 Kf2 Ke4 Kg1 Kf3 Kh1 Kg3 Ng1 Bg2#
pure model ideal switchback self-block nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.
Deepest dual problems
Deepest dual with different first and last moves: h#3. The deepest dual overall is h#8, where the two solutions share a first or a last move.
h#3
7B/6n1/8/8/8/2k5/1Q6/K7 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kd3 Qb3+ Kd2 Bxg7 Kc1 Bh6#
- Kc4 Qc2+ Kb4 Bxg7 Ka3 Bf8#
mirror single-piece single-piece:black
Note: the side to move is in check in the diagram.
h#3
8/8/8/8/8/1B1k4/2Q5/K1n5 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Ke3 Qe4+ Kf2 Bd5 Kg1 Qg2#
- Kd4 Qg6 Kc5 Kb2 Kb4 Qb6#
pure model single-piece single-piece:black nocapture
Note: the side to move is in check in the diagram.
h#3
8/8/8/8/n2k4/2Q5/3B4/K7 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Ke4 Qb4+ Kd3 Be1 Kc2 Qb1#
- Kd5 Qa5+ Kc4 Kb1 Kb3 Qb4#
single-piece single-piece:black nocapture
Note: the side to move is in check in the diagram.