h#7
6Qk/8/8/8/8/1P6/1P6/2K5 b - - 0 1
- Kxg8 b4 Kf7 b5 Ke6 b6 Kd5 b7 Kc4 b3+ Kxb3 b8=Q+ Ka2 Qb2#
promotion single-piece single-piece:black phoenix
Note: the side to move is in check in the diagram; the solution begins with a capture.
KQPPvk
5 pieces.
- h#8
- longest mate
- h#7
- deepest unique
- 37
- positions at that depth
- h#7
- deepest dual
- h#4.5
- deepest strict dual
- 186,614,038
- positions with a helpmate
- 16,745,749
- with a unique solution
- 266,305,536
- cells in the plane
- 154,636,748 bytes
- on disk
Deepest unique problems
h#7
8/8/8/8/6Qk/6P1/K5P1/8 b - - 0 1
- Kxg4 Ka3 Kf5 g4+ Ke4 g5 Kd3 g6 Kc2 g7 Kb1 g8=Q Ka1 Qa2#
promotion single-piece single-piece:black phoenix umnov
Note: the diagram has no legal last move, so it cannot arise in a game.
h#7
8/8/8/8/K7/PP6/6Q1/6k1 b - - 0 1
- Kxg2 Kb4 Kf3 a4 Ke4 a5 Kd5 a6 Kc6 a7 Kb7 Kc5 Ka6 a8=Q#
pure model mirror promotion single-piece single-piece:black phoenix 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#4.5. The deepest dual overall is h#7, where the two solutions share a first or a last move.
Only one position exists at this depth.
h#4.5
8/8/8/7k/8/1PQ5/KP6/8 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kb1 Kg4 Qg7+ Kf3 Kc2 Kf2 Kd3 Ke1 Qg1#
- Ka3 Kg6 Kb4 Kf7 Kc5 Ke8 Kd6 Kd8 Qh8#