h#5
8/2r5/8/8/8/1b5k/6Q1/K7 b - - 0 1
- Kh4 Qc6 Kg3 Kb2 Kf2 Kc3 Ke1 Kd3 Kd1 Qh1#
pure model mirror single-piece single-piece:black nocapture nocheck
Note: the side to move is in check in the diagram.
KQvkrb
5 pieces.
- h#6.5
- longest mate
- h#5
- deepest unique
- 23
- positions at that depth
- h#5
- deepest dual
- h#4.5
- deepest strict dual
- 138,321,798
- positions with a helpmate
- 6,039,906
- with a unique solution
- 121,110,528
- cells in the plane
- 88,843,127 bytes
- on disk
Deepest unique problems
h#5
8/8/8/5r2/6k1/b5Q1/8/K7 b - - 0 1
- Kh5 Qxa3 Kg4 Qa2 Kf3 Kb2 Ke2 Kc3+ Kd1 Qd2#
switchback single-piece single-piece:black
Note: the side to move is in check in the diagram.
h#5
2Qk4/8/8/8/8/5b2/5r2/1K6 b - - 0 1
- Ke7 Kc1 Rd2 Kxd2 Kf6 Ke3 Kg5 Kxf3 Kh4 Qg4#
Note: the side to move is in check in the diagram.
Deepest dual problems
Deepest dual with different first and last moves: h#4.5. The deepest dual overall is h#5, where the two solutions share a first or a last move.
h#4.5
8/8/8/6k1/1b6/r7/1Q6/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kb1 Rh3 Kc2 Rh5 Kd3 Be1 Ke4 Bh4 Qg7#
- Qxa3 Kf4 Qa2 Ke3 Kb2 Kd2 Kb3+ Kc1 Qc2#
pure model ideal self-block single-piece single-piece:black
Note: the side to move is in check in the diagram.
h#4.5
8/8/Q7/6k1/1b6/r7/8/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kb2 Rg3 Qd3 Be7 Kc3 Kf4 Kd4 Bg5 Qe4#
- Qxa3 Kf4 Qa2 Ke3 Kb2 Kd2 Kb3+ Kc1 Qc2#
self-block single-piece single-piece:black
Note: the side to move is in check in the diagram.
h#4.5
8/8/8/2b4k/8/1r6/2Q5/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Ka2 Kg4 Kxb3 Kf3 Qf5+ Ke2 Kc3 Kd1 Qf1#
- Qxb3 Kg4 Qa2 Kf3 Kb2 Ke2 Kc3+ Kd1 Qd2#