%TITLE Longest mate in King and Bishop versus King and Bishop endgame: an endgame analysis by Joe Leslie-Hurd
%HEADING Longest mate in King and Bishop versus King and Bishop endgame
%SUBHEADING Mate in 1
%FOOTER An <a href="http://www.gilith/chess/endgames">endgame analysis</a> by <a href="http://www.gilith.com/">Joe Leslie-Hurd</a> on 16 February 2005.

[Event "Endgame analysis: longest mate in King, Queen and Bishop versus King"]
[Site "Oxford ENG"]
[Date "2005.02.16"]
[Round "-"]
[White "Perfect"]
[Black "Perfect"]
[Result "1-0"]
[Time "07:10:34"]
[Annotator "Joe Leslie-Hurd"]
[WhiteType "program"]
[BlackType "program"]
[SetUp "1"]
[FEN "KQ6/8/8/8/8/5k2/5B2/8 w - - 0 1"]

{Mate in 8 with Ba7, Bb6, Bc5, Bd4, Be1, Bg1, Bg3, Bh4, Qa7, Qb2, Qb6, Qf8+, Qg3+ and Qh2. Worse are Ka7, Kb7 and Qb3+ with mate in 9, Be3, Qb1, Qb4, Qb5, Qb7+, Qc7, Qc8, Qd6, Qd8, Qe5, Qe8, Qg8 and Qh8 with mate in 10, and Qf4+ which throws away the win.}
1. Qb6 {White mates in 7 after Ke4. Worse are Ke2, Kf4, Kg2 and Kg4 when White mates in 6.}
1... Ke4 {Mate in 7 with Qa5, Qb3, Qb5, Qb7+, Qc5, Qc6+, Qd4+, Qe3+, Qe6+, Qf6 and Qg6+. Worse are Bc5, Bd4, Be1, Be3, Bg1, Bg3, Bh4, Ka7, Kb7, Kb8, Qa7, Qb1+, Qb2, Qb4+, Qc7, Qd6, Qd8 and Qh6 with mate in 8, and Qa6 and Qb8 with mate in 9.}
2. Qd4+ {White mates in 6 after Kf5. Worse is Kf3 when White mates in 5.}
2... Kf5 {Mate in 6 with Bh4. Worse are Be1, Be3, Bg1, Bg3, Ka7, Kb7, Kb8, Qa4, Qb4, Qc4, Qc5+, Qd3+, Qd5+, Qe3 and Qh4 with mate in 7, Qa1, Qa7, Qb2, Qb6, Qc3, Qd1, Qd2, Qd6, Qd7+, Qd8, Qg7 and Qh8 with mate in 8, and Qe4+, Qe5+, Qf4+, Qf6+ and Qg4+ which throw away the win.}
3. Bh4 {White mates in 5 after Ke6. Worse is Kg6 when White mates in 4.}
3... Ke6 {Mate in 5 with Qe4+. Worse are Kb7, Qc5, Qf4 and Qg4+ with mate in 6, Bd8, Be1, Bf2, Bf6, Bg3, Bg5, Ka7, Kb8, Qa4, Qb2, Qb4, Qc3, Qc4+, Qd1, Qd2, Qd3, Qd8, Qe3+, Qf2, Qf6+, Qg1 and Qg7 with mate in 7, Be7, Qa1, Qa7, Qb6+ and Qh8 with mate in 8, and Qd5+, Qd6+, Qd7+ and Qe5+ which throw away the win.}
4. Qe4+ {White mates in 4 after Kf7. Worse are Kd6 and Kd7 when White mates in 3.}
4... Kf7 {Mate in 4 with Bg5. Worse are Bd8, Ka7, Kb7, Kb8, Qc6, Qd5+, Qe5, Qe7+, Qf3+ and Qf5+ with mate in 5, Be1, Be7, Bf2, Bg3, Qa4, Qb1, Qb4, Qb7+, Qc2, Qc4+, Qd3, Qd4, Qe1, Qe2, Qe3, Qf4+, Qg2, Qg4, Qh1 and Qh7+ with mate in 6, Bf6 with mate in 9, and Qe6+, Qe8+ and Qg6+ which throw away the win.}
5. Bg5 {White mates in 3 after Kg7 and Kg8. Worse is Kf8 when White mates in 2.}
5... Kg7 {Mate in 3 with Qe8. Worse are Qc6, Qe6, Qf4 and Qf5 with mate in 4, Bd8, Be7, Bh4, Ka7, Kb7, Kb8, Qb1, Qc2, Qd3, Qd5 and Qf3 with mate in 5, Bc1, Bd2, Be3, Bf4, Qa4, Qb4, Qc4, Qd4+, Qe1, Qe2, Qe3, Qe5+, Qe7+, Qg2, Qg4 and Qh4 with mate in 6, Qb7+ and Qh1 with mate in 7, Bh6+ with mate in 8, Bf6+ with mate in 9, and Qg6+ and Qh7+ which throw away the win.}
6. Qe8 {White mates in 2 after Kh7.}
6... Kh7 {Mate in 2 with Qf7+. Worse are Bf6 with mate in 3, Bc1, Bd2, Bd8, Be3, Be7, Bf4, Bh4, Ka7, Kb7, Kb8, Qc6, Qe4+, Qe6, Qf8 and Qh5+ with mate in 4, Qa4, Qb5, Qb8, Qc8, Qd7+, Qd8, Qe1, Qe2, Qe3, Qe5 and Qe7+ with mate in 6, Bh6 with mate in 8, and Qg6+, Qg8+ and Qh8+ which throw away the win.}
7. Qf7+ {White mates in 1 after Kh8.}
7... Kh8 {Mate in 1 with Bf6#. Worse are Qa7, Qb7, Qc7, Qd7, Qe7, Qf6+ and Qf8+ with mate in 3, Qe6, Qe8+, Qf1, Qf2, Qf3, Qf4, Qf5 and Qh5+ with mate in 4, Qa2, Qb3, Qc4 and Qd5 with mate in 5, and Bc1, Bd2, Bd8, Be3, Be7, Bf4, Bh4, Bh6, Ka7, Kb7, Kb8, Qg6, Qg7+, Qg8+ and Qh7+ which throw away the win.}
8. Bf6# {Checkmate.} 1-0
