h#11.5
8/8/2k2p2/8/3K4/8/8/1B5b w - - 0 1
- Ke3 f5 Kf2 f4 Kg1 f3 Kxh1 f2 Kg2 f1=N Kf2 Kd5 Ba2+ Ke4 Ke1 Kf3 Be6 Kg2 Bh3+ Kh1 Kf2 Nh2 Bg2#
pure model ideal promotion underpromotion switchback closed-walk self-block kniest umnov
KBvkbp
5 pieces.
- h#16
- longest mate
- h#11.5
- deepest unique
- 8
- positions at that depth
- h#12
- deepest dual
- h#7.5
- deepest strict dual
- 527,518,663
- positions with a helpmate
- 2,145,200
- with a unique solution
- 355,074,048
- cells in the plane
- 167,116,663 bytes
- on disk
Deepest unique problems
h#11.5
8/8/2p2k2/3K4/8/8/8/b5B1 w - - 0 1
- Kc4 c5 Kb3 c4+ Ka2 c3 Kxa1 c2 Kb2 c1=N Kc2 Ke5 Bh2+ Kd4 Kd1 Kc3 Bd6 Kb2 Ba3+ Ka1 Kc2 Na2 Bb2#
pure model ideal promotion underpromotion switchback self-block kniest umnov
Note: the side to move is in check in the diagram.
h#11.5
8/5p1B/2k5/8/3K4/8/8/7b w - - 0 1
- Ke3 f5 Kf2 f4 Kg1 f3 Kxh1 f2 Kg2 f1=N Kf2 Kd5 Bg8+ Ke4 Ke1 Kf3 Be6 Kg2 Bh3+ Kh1 Kf2 Nh2 Bg2#
pure model ideal promotion underpromotion excelsior excelsior:black switchback closed-walk self-block kniest umnov
Deepest dual problems
Deepest dual with different first and last moves: h#7.5. The deepest dual overall is h#12, where the two solutions share a first or a last move.
h#7.5
8/K1p5/8/8/8/8/B7/3b3k w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Bb3 c5 Kb6 c4 Kc5 c3 Kd4 c2 Ke3 c1=B+ Kf2 Bf4 Bxd1 Bh2 Bf3#
- Be6 c5 Kb6 c4 Kc5 c3 Kd4 c2 Ke3 c1=B+ Kf2 Bf4 Bh3 Bh2 Bg2#
pure model promotion underpromotion excelsior excelsior:black self-block single-piece single-piece:black umnov
h#7.5
1K6/2p5/8/7b/8/8/B7/7k w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Be6 c5 Kc7 c4 Kd6 c3 Ke5 c2 Kf4 c1=B+ Kg3 Be3 Bh3 Bg1 Bg2#
- Bf7 c5 Kc7 c4 Kd6 c3 Ke5 c2 Kf4 c1=B+ Kg3 Be3 Bxh5 Bg1 Bf3#
pure model promotion underpromotion excelsior excelsior:black self-block single-piece single-piece:black umnov
h#7.5
8/K7/2k5/8/6Bp/8/8/5b2 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Bd7+ Kd5 Kb6 Ke4 Kc5 Kf3 Kd4 Kg2 Ke3 Kh1 Kf2 h3 Kxf1 h2 Bc6#
- Bc8 Kd5 Kb6 Ke4 Kc5 Kf3 Kd4 Kg2 Ke3 Kh1 Kf2 h3 Kxf1 h2 Bb7#