White to move and win

clandarkfire
Posers and Puzzles 17 Jun '08 00:51
1. clandarkfire
Grammar Nazi
17 Jun '08 00:51
White to move and win

A tough one. It took me quite a while.
2. slappy115
Slappy slap slap
17 Jun '08 14:33
Originally posted by clandarkfire
White to move and win

[fen]k6b/8/B1N3K1/8/3p4/8/8/8[/fen]

A tough one. It took me quite a while.
Would it be Kf5?
3. 17 Jun '08 15:30
Kh7 - h6 - g5?

Of course, this solution relies on my thinking that BN v B is won, but I cannaer remember.
4. 17 Jun '08 15:56
wait a sec, Bd3, Nd8+ and Nf7 gives the appearance of ownage.
5. 17 Jun '08 16:13
White clearly needs to keep both his men alive, or else he will have insufficient material to mate, even if he nabs both the bishop and the pawn.

White bishop prevents black pawn from moving forward, but the black bishop prevents the king from taking the pawn. Black bishop also makes a knight capture a draw...

Looking at this again, Kf7 should put Black in zugzwang. His king is immobile, and whichever piece he moves gets captured. I am thinking Black will opt to lose his pawn as it will fall if the bishop guarding it falls. White is then left with KBN v KB.
6. 17 Jun '08 16:14
1 Bd3 Kb7
2 Nd8+ Kb6
3 Nf7 Kc5
4 Nxh8 Kb4
5 Nf7 Kc3
6 Ne5

Eventually Black's d-pawn falls leaving a won B+N+K v K endgame.
7. 17 Jun '08 16:15
1 Bd3 Kb7
2 Nd8+ Kb6
3 Nf7 Kc5
4 Nxh8 Kb4
5 Nf7 Kc3
6 Ne5

Eventually Black's d-pawn falls leaving a won B+N+K v K endgame.
I like this idea better than the one I saw. Not sure how BN v B works out, but endgames that close tend to be drawn.
8. 17 Jun '08 16:32
Originally posted by geepamoogle
I like this idea better than the one I saw. Not sure how BN v B works out, but endgames that close tend to be drawn.
I was almost swayed by 1 Kf7 but Black can sacrifice the pawn with 1... d3! giving his king a bolt hole on b7 after the bishop captures. In the process of trying to herd the Black king back to the edge of the board the knight will have to land on a dark square and all Black has to do is swap bishop for knight and it's a draw.
9. wolfgang59
17 Jun '08 17:09
Originally posted by clandarkfire
White to move and win

[fen]k6b/8/B1N3K1/8/3p4/8/8/8[/fen]

A tough one. It took me quite a while.
In my naivety I thought
1. Kf7, d3
2. Ke6, d2
3. Kd7, d1=Q
4. Kc8, ?
5. Bb7 mate

Are you sure the pawn starts there?
10. 17 Jun '08 17:14
Originally posted by wolfgang59
In my naivety I thought
1. Kf7, d3
2. Ke6, d2
3. Kd7, d1=Q
4. Kc8, ?
5. Bb7 mate

Are you sure the pawn starts there?
My first idea too, but Black can just play 4. ... Qb1 and no mate and disaster for White. 1. Bd3 is the right way to go (zugzwang).

Knight and Bishop vs. Bishop is a draw.
11. clandarkfire
Grammar Nazi
17 Jun '08 18:38
1 Bd3 Kb7
2 Nd8+ Kb6
3 Nf7 Kc5
4 Nxh8 Kb4
5 Nf7 Kc3
6 Ne5

Eventually Black's d-pawn falls leaving a won B+N+K v K endgame.
Yes, this is the one and only solution that works. You would never believe how long it took me. The Idea is zugzwang, (forcing black to move, when all his moves are bad.)
12. clandarkfire
Grammar Nazi
17 Jun '08 18:45

white to move and win
13. 17 Jun '08 20:441 edit
Originally posted by clandarkfire

[fen]3k2r1/2R5/7p/p4K1B/P7/7P/8/8[/fen]

white to move and win
1. Ra7?

I think? It seems like a sensible choice.
14. wolfgang59
17 Jun '08 21:04
Originally posted by kfennessy
1. Ra7?

I think? It seems like a sensible choice.
Rh7 looks better. Protects the bishop (I think white eventually mates if black takes it after the check) and attacks the pawn.

Ra7 threatens nothing . white cannot take the a-pawn because of the check.
15. 17 Jun '08 21:231 edit
I think I found it after thinking about the first puzzle where the black piece got trapped.

1. Rc4 Rg5+ 2. Ke6 and now if Rxh5 then 3. h4 and black rook is trapped (and if black moves king then mate).

edit: one more thing has to be looked at. if black doesnt take the bishop and plays 2. .. Rc5 which attacks rook and prepares a stalemate then 3. Be2 and both white pieces are saved which should be a won endgame right?