White to move. This requires very deep calculation.
Daily Chess Improvement: Calculations Required!
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White to move. This requires very deep calculation.
White can’t play 1. Ne7+ because Qxe7 wins on material, 1. Qg4 Qxf6 2. Bg5 3. Qe6 Bh6 4. g6 and White is still down too much material
1. Nh6+ gxh6 2. Qg4+ Kh8 3. Qg7#
1. Nh6+ Kh8 2. fxg7+ Kxg7 3. Qg4+ Kh8 and Rxf7 doesn’t work but maybe a move earlier
1. Nh6+ Kh8 2. fxg7+ Kxg7 3. Rxf7+ Rxf7 4. Qg4+ Kf8 5. Qg8+ Ke7 6. Qxf7#
Okay 1. Qg4 g6 2. Qg5 Kh8 maybe, I didn’t notice 1. … Qxf6 2. Nh6+
James,
I think you are on the right track with
1. Nh6 Kh8
2. fg7 Kg7
3. Qg4 Kh8
I can’t be sure 4.Rf7 wins or not, but it should gain most of the lost material back:
4. Rf7?! Qf6!?
5. Rf6 Rf6
6. Nf7
Now, on your fourth move for white, I judge it dubious because there is something much better at move 4 for white, and your hint is in the line above. I haven’t worked it all out, I would have to put this on the chess board for real accuracy, but I think it is likely a forced mate with the white queen and the king’s bishop in 14 moves total taking your first three moves for each player which I have shamelessly borrowed from your line since my first thought was 1.Qg4 which I now don’t think does anything but lose for white right now.
1. Nh6+ Kh8 2. fxg7+ Kxg7 3. Rxf7+ Kh8 4. Qh5 threatening to sacrifice the rook at h7 followed by Nf5#
James,
That line is interesting, but you might want to play an immediate 4.Rh7 instead of playing 4.Qh5 first because black can play 4. ……Rc7 if you don’t. Again, I would have to put this on the board and really look at it a long time just to be sure and I don’t have time for that this afternoon- a pity- the one really good problem posted here this week, and I don’t have time to work on it.
1. Nh6+ Kh8 2. fxg7+ Kxg7 3. Qg4+ Kh8 4.Nxf7+ wins.
Nh6+ Kh8, Pxg7+ Kxg7, Qh4+ Kh8, Rxf7 Rg8, Qf5 Rg7, Rxg7 Kxg7, Qf7+ Kh8, Nf5 Qc7, Qf6+ Qg7, Qxg7#
1. Nh6+ Kh8
2. fxg7+ Kxg7
3. Qg4+ Kh8
4. Nxf7+ Rxf7
5. Rxf7 Qg8
6. Qf5 Qg6
7. Rf8+ Kg7
8. Qd7+ Kxf8
9. Bh6+ Qg7
10. Bxg7#
The sixth move for the black was weak.
I’m stuck with this variation
1. Nh6+ Kh8
2. fxg7+ Kxg7
3. Qg4+ Kh8
4. Nxf7+ Rxf7
5. Rxf7 Qg8
6. Qf5 Qxf7
7. Qxf7 c4
I can’t win it in 12 moves.
5. Bxf7 looks more lethal to me e.g. Qf8 6. Bg5 Bc8 7. Bh6
Alena,
This is the line I was thinking about last night- especially the second variation where black has played 6. …Qxf7, but I think that 7.Bxf7 is better than 7.Qxf7:
7. Bf7 Bd8 (trying Rg8 or h6/h5 is shorter mates)
8. Bg5!
And I don’t see how black avoids getting mated here in 6 moves or less- black can’t take at g5, all the other moves allow 9.Bf6, and the combo queen and king’s bishop will mate the black king after that- right?
Yes, you are right Yancey.
7. Bxf7 Bd8
8. Bg5 Kg7
9. Be6 Bxg5
10. Qxg5+ Kf8
11. Qg8+ Ke7
12. Qf7+ Kd8
13. Qd7#
I can’t win it in 12 moves, again. Yancey, Where did I loose one move?
I don’t think you lost a move based on the line you give. Mate in 13 . However, I think James might well have a shorter line with 3.Rf7 and 4.Rh7. Gotta work it out later if I have time.
1. Nh6+ Kh8 2. fxg7+ Kxg7 3. Bxf7 Kh8 4. Qg4 and the threat of Bg5 heading for f6 is very strong.
I forgot about the N attacking the Q
1. Nh6+ Kh8 2. fxg7+ Kxg7 3. Qg4+ Kh8 4. Bxf7 gives the same position.
Finally had time to look at the line James provided above in great detail, and it is the shortest win:
1. Nh6! Kh8 (gh6 2.Qg4 Kh8 3.Qg7#)
2. fg7 Kg7
3. Rh7!!
Of course, 3.Qg4 also wins as Alena showed above, but 3.Rh7 is shorter and quite spectacular. Continuing:
3. ………..Kh8
Or [3. …Rf7 4.Qg4 Qg5 (or 4. …Kf8 5.Qg8 Ke7 6.Qxf7#; or 4. ….Kf6 5.Qg5#; or 4. …Kh8 5.Nf7#) 5.Qg5 Kf8 6.Qg8 Ke7 7.Qf7 Kd8 8.Bg5#; or 3. ….Kg6 4.Qg4 Qg5 5.Qg5#]. Continuing:
4. Rh7!! Kh7 (a forced feeding of a rook!)
5. Qh5!
Probably the only move here for white that doesn’t lose, but it wins convincingly. The threat is 6.Nf5 with a discovered mate. The best black can do here is delay this since there are no safe squares from which any of black’s pieces can attack the white queen. He can delay things with queen sacrifices at g5 or h4, he can deliver a worthless check from f1 with the rook and then sacrifice it at h1 to buy two moves, he can block the king’s bishop’s line with Nc3, b3, c4, d5, or Bd5, but none of those prevent mate. By my count the longest mate is the direct combination of all those delays…
5. …………Rf1
6. Kh2 Rh1
7. Kh1 Qh4
8. Qh4 b3
9. Nf5 Kg8 (or Kg6 10.Qh6 Kf7 11.Qg7 with 12.Qe7# on the next move)
10. Qg5 and mate will come no later than the 12th move regardless of where the black king goes now.
That, of course, should be 3.Rf7!! as the first rook move. I don’t proofread as often as I should.