White has no time for Qd7 to win, though I think he might draw with this move:
1. Qd7 Qc4 2. Ka5
And, now, if the black queen leaves the c-file without checking the white king, black will lose:
2. …..Qd4 3. Qc7 Ka7 4. b8(Q)#
Moves like 2. …Qd5 are no better:
2. …..Qd5 3. Ka6 Qa2 4. Kb5 Qb3 5. Ka6 and white is just careful to not allow the bishop in on the action with check, he should be able to draw with perpetual check if needed. At move 2, black could try Bd4, and this is less clear to me, but in 10 minutes I can’t see a win for black:
So, white draws with 1.Qd7. So, now the question is- can white win this? I think white needs to protect c4 and/or d4 to have any winning chances. My very first instinct is to protect both pawns by playing d5, but this loses:
1. d5 Qh8!
And, now, white is in a world of trouble as black is threatening mate starting with Qa1+:
2. Qe5 Qd8! 3. Kb5 Qb6 4. Ka4 Bc5 (best move) 5. Qe8 Kb7 6. Qd7 Ka6 7. Qc8 Ka7 8. Qd7 Qb7 and white will have to exchange the queens at either b7 or b5 and black will win with the outside passers. At move 2, white does no better with moves like
2. Qd7 Qa1 3. Kb5 Qb2 4. Ka4 Qb7! 5. Qe8
Moves like 5.Qg5 are surely mating nets after 5. …Bc5. Cont.:
Took me a while to find this move in this line- I wasted 20 minutes looking at everything else, including the long lines starting with 8. …Qb7. Cont.:
11.Qa3 g2 12.Qa1 Qb6
And the g-pawn will queen and win the game for black. So, 1.d5 loses for white. My second instinct is to protect c4 with Qe2, but it doesn’t take long to find many adequate replies for black as the pressure on his king is no longer an issue:
1. Qe2 Bd4 (g3 or h3 OK, too)
The problem is that with the queen at e2, white has no counterplay and black is just going to push the g-pawn down white’s throat. Indeed, I see no reason to go any further in this line as it is easily won game for black now.
Due to length, I will continue in my next comment.
At first, I had dismissed 1.Kb5 to protect c4 as this seems to just drop the b7 pawn, but a closer look reveals that Kb7 might not be so good as white can take at d7 with check in that case:
1. Kb5 Kb7 2. Qd7 Ka8 (Kb8 3.Qc7 Ka8 4.d7+-) 3. Qc6 Kb8 4. Qc7 Ka8 5. d7 and there is no defense for black, so he cannot play Kb7 with his first move. Let’s now move to the alternatives:
1. Kb5 Bd4 2. Qd7 and what can black do to prevent Qc7 followed by b8(Q)? Or
1. Kb5 Qe6 2. Qd8 Kb7 (Ka7 3.b8(Q)#) 3. Qc7 Ka8 4. Ka6 and the various mate threats- Qa7, Qb7, or Qc8- can’t all be prevented. Here, inititially, I thought 1. …Ka7 would be a quick win for white, but it is not quite that easy I found:
1. Kb5 Ka7! 2. Qd7 Qb8 (only move I find)
Here, I have looked at every possibility for white, and the winning move I find is
I am far from certain, but every other move for white here looked losing. However, now, the game looks lost for black. Continuing:
5. …..Qg8 (Qb8 is below) 6. Kd4 Qh8 7. Kc5 Qh5 8. Kb4 and there is now no further checks on the white king and white will play b8(Q) with double check on the black king, or, if black plays Ka6, white mates with b8(N). At move 5 above, black does no better with
5. …..Qb8 6. Qb8! Kb8 7. Kd4! h3 (Kb7 is below) 8. d7 Kc7 (h2 9.d8(Q)+-) 9. d8(Q)Kd8 10.b8(Q)wins easily for white. At move 7 immediately above, black still loses with
7. …..Kb7 8. Ke3!
And white is in the square of both black pawns and will be able to stop them while black’s king will not be able stop all three of white’s pawns. Cont.:
8. …..h3 (what else?) 9. Kf2 h2 10.Kg2 g3 11.f5 Kc6 12.f6 Kd6 13.c5 Kd7 (Kc5 14.f7+-) 14.c6 Kd8 (Kc6 15.f7+-) 15.f7 Ke7 16.c7 and one of the pawns queens.
Looks like white is in trouble.
d5 Qh8
Qd7 Qa1
Kg5 Qb2
Kc6 Kb8 what else?
Qd8 Ka7
b8=Q Qb8
Qa5
1. Kb5 wins
I think the b7 pawn is immune after Kb5! followed by Qxd7. Black queen is always one move too slow.
anon 143 – kc6 kb8 what else
Qb6# checkmate!!! – thats what!
White has no time for Qd7 to win, though I think he might draw with this move:
1. Qd7 Qc4
2. Ka5
And, now, if the black queen leaves the c-file without checking the white king, black will lose:
2. …..Qd4
3. Qc7 Ka7
4. b8(Q)#
Moves like 2. …Qd5 are no better:
2. …..Qd5
3. Ka6 Qa2
4. Kb5 Qb3
5. Ka6 and white is just careful to not allow the bishop in on the action with check, he should be able to draw with perpetual check if needed. At move 2, black could try Bd4, and this is less clear to me, but in 10 minutes I can’t see a win for black:
2. …..Bd4
3. Qd8 Kb7 (only move)
4. Qd7 Kb8
5. Qe8! Ka7 (Kb7=; Qc8?? 6.d7+-)
6. Qd7=
So, white draws with 1.Qd7. So, now the question is- can white win this? I think white needs to protect c4 and/or d4 to have any winning chances. My very first instinct is to protect both pawns by playing d5, but this loses:
1. d5 Qh8!
And, now, white is in a world of trouble as black is threatening mate starting with Qa1+:
2. Qe5 Qd8!
3. Kb5 Qb6
4. Ka4 Bc5 (best move)
5. Qe8 Kb7
6. Qd7 Ka6
7. Qc8 Ka7
8. Qd7 Qb7 and white will have to exchange the queens at either b7 or b5 and black will win with the outside passers. At move 2, white does no better with moves like
2. Qd7 Qa1
3. Kb5 Qb2
4. Ka4 Qb7!
5. Qe8
Moves like 5.Qg5 are surely mating nets after 5. …Bc5. Cont.:
5. …..Ka7
6. Qe1 Bc5
7. d7 Qd7
8. Kb3 g3 (best move IMO)
9. Qa5 Kb7
10.Qc5 Qc7!
Took me a while to find this move in this line- I wasted 20 minutes looking at everything else, including the long lines starting with 8. …Qb7. Cont.:
11.Qa3 g2
12.Qa1 Qb6
And the g-pawn will queen and win the game for black. So, 1.d5 loses for white. My second instinct is to protect c4 with Qe2, but it doesn’t take long to find many adequate replies for black as the pressure on his king is no longer an issue:
1. Qe2 Bd4 (g3 or h3 OK, too)
The problem is that with the queen at e2, white has no counterplay and black is just going to push the g-pawn down white’s throat. Indeed, I see no reason to go any further in this line as it is easily won game for black now.
Due to length, I will continue in my next comment.
At first, I had dismissed 1.Kb5 to protect c4 as this seems to just drop the b7 pawn, but a closer look reveals that Kb7 might not be so good as white can take at d7 with check in that case:
1. Kb5 Kb7
2. Qd7 Ka8 (Kb8 3.Qc7 Ka8 4.d7+-)
3. Qc6 Kb8
4. Qc7 Ka8
5. d7 and there is no defense for black, so he cannot play Kb7 with his first move. Let’s now move to the alternatives:
1. Kb5 Bd4
2. Qd7 and what can black do to prevent Qc7 followed by b8(Q)? Or
1. Kb5 Qe6
2. Qd8 Kb7 (Ka7 3.b8(Q)#)
3. Qc7 Ka8
4. Ka6 and the various mate threats- Qa7, Qb7, or Qc8- can’t all be prevented. Here, inititially, I thought 1. …Ka7 would be a quick win for white, but it is not quite that easy I found:
1. Kb5 Ka7!
2. Qd7 Qb8 (only move I find)
Here, I have looked at every possibility for white, and the winning move I find is
3. Kc6 Bd4 (again, only move)
4. Qc7! Qe8 (only move)
5. Kd5!
I am far from certain, but every other move for white here looked losing. However, now, the game looks lost for black. Continuing:
5. …..Qg8 (Qb8 is below)
6. Kd4 Qh8
7. Kc5 Qh5
8. Kb4 and there is now no further checks on the white king and white will play b8(Q) with double check on the black king, or, if black plays Ka6, white mates with b8(N). At move 5 above, black does no better with
5. …..Qb8
6. Qb8! Kb8
7. Kd4! h3 (Kb7 is below)
8. d7 Kc7 (h2 9.d8(Q)+-)
9. d8(Q)Kd8
10.b8(Q)wins easily for white. At move 7 immediately above, black still loses with
7. …..Kb7
8. Ke3!
And white is in the square of both black pawns and will be able to stop them while black’s king will not be able stop all three of white’s pawns. Cont.:
8. …..h3 (what else?)
9. Kf2 h2
10.Kg2 g3
11.f5 Kc6
12.f6 Kd6
13.c5 Kd7 (Kc5 14.f7+-)
14.c6 Kd8 (Kc6 15.f7+-)
15.f7 Ke7
16.c7 and one of the pawns queens.