I was having a look at it last night without much solving it either.
A couple of thoughts I had were:
As stalemate doesn't look an option, white must play Ng4 threatening mate or promotion with check at some point - as soon as black gets to play f1=Q someone has to win.
Bishop move looks unlikely too, I can't see a threat.
So that leaves either f7+ or fxh7. I'm leaning towards the latter as the first move, I've had a look at a few lines yet not manage to conclusively show either way as being correct (but did get to see possibilities if black plays both badly).
Originally posted by Peakiteif 1. g7+, Nxg7 and white quickly runs out of threats.
I was having a look at it last night without much solving it either.
A couple of thoughts I had were:
As stalemate doesn't look an option, white must play Ng4 threatening mate or promotion with check at some point - as soon as black gets to play f1=Q someone has to win.
Bishop move looks unlikely too, I can't see a threat.
So that leaves either ...[text shortened]... show either way as being correct (but did get to see possibilities if black plays both badly).
if 1. gxh7, Kxh7
2. g6+, Kg8 and white quickly runs out of threats.
And I grant that if black played badly enough, this game would end in a draw or possible defeat (if they do something really dumb). But GOOD chess puzzles are designed so that everything is forced after the first move. Not forced as in the other side only has one option to reply with, but forced as in there is a response to every possible move that the opposition could make.
Originally posted by theangrystudentAs I said, couldn't identify either way.
if 1. g7+, Nxg7 and white quickly runs out of threats.
if 1. gxh7, Kxh7
2. g6+, Kg8 and white quickly runs out of threats.
And I grant that if black played badly enough, this game would end in a draw or possible defeat (if they do something really dumb). But GOOD chess puzzles are designed so that everything is forced after the first mo ...[text shortened]... but forced as in there is a response to every possible move that the opposition could make.
Another think and Ba3, intending to move onto b2 could be something - setting up a potential double check, but I still think black can avoid it.
1. B-a3, f1 and black gets a queen
2. B-b2, Qa6+
3. K-(b1 or b-3), gxh
The knight and bishop alone are unable to mate the king, the black queen is protecting black's last pawn, the black pawn is preventing the white pawn from doing anything... so white just moves his king along the white squares and it should be an easy victory from there.
[fen]5B1k/7p/6P1/4NnP1/8/8/K4p2/8 w - - 0 1[/fen]1.g7+!
If 1...Kg8 2.Ng4 threatens Nf6+ and Nxf2, so...
1...Nxg7 2.Nf7+! Kg8 3.Bc5!
Threatens Bxf2 and Nh6+/Nf7+ perpetual check
3...f1Q 4.Nh6+ Kg8 5.Bd4!!
...and Black can make absolutely no progress. His King is stuck in the corner, his Knight is pinned, he can't win the white Bishop with checks, and he can't play ...Qxg5+ due to Nf7+.
DRAW