K+B+N vs K

Was this from one of your games?

no, but if it ever comes up, I know how to deliver the checkmate.

K+N+B vs K is possibly the hardest checkmates to deliver.

Thanks for making the improvements!

There are sites that help you practice the K+N+B vs K endgame.

PS: If anyone notices a better variation, please let me know, I am still not 100% confident in my analisys of this particular line

There are two harder basic mates:

White: K + 2 N vs K +P, and K+Q vs K+R

 oh, hi ther smyslovFan. Thanks for the improvments. I will try to put them into the puzzle. I'm going to write them down then you should delete your comment so others can try the puzzle without the extra help.

:)

It makes it harder to close the net. Try it and you'll see. 

The key improvement tho is 8.Nf5!

This ending is extremely rare .  I have had it once in more than 30 years of tournament play and have never had the K+ 2 Bs  v K  , though its far easier to do than KBN v K .  I think you can practice any of these mates here on chess.com and I sometimes practice them on ICC . 

:)

Hey Reb, I know it's rare, just thought it would make a fun puzzle, and learning it can't hurt. I heard a storry about a guy at a master level tournament who actually ended up in this position. it was GM vs IM, the GM had the knight and bishop, but he also was low on time, with just a few minutes left. the game ended in a draw (because of time or the 50 move rule, i don't remember). So i figured it was worth learning. Just in case.

g-man, I'll save you some time. I didn't work everything out myself, I checked out the tablebase (after the "solution" said I'd made some wrong moves). Plug in the FEN code without any of the [, ", FEN stuff and see where the improvements are. 

Here's a link:

http://www.k4it.de/index.php?topic=egtb&lang=en

I see why your tablebase prefers ---, but It still is no better. It loses 1 move later, and most people aren't going to notice that. as for 8Nf5, it makes no difference at all, just changes the order that the waiting move is made in, and in my opinion, it is more "sound" to make the waiting move first.

If it loses one move later, it's better. At least, that's the logic of puzzles.

I will keep it as it is, as the point of a puzzle is to test the user's knowledge. considering that they will still use the same concept to mate, an extra move does not improve the puzzle. Thank you very much for your opinion. and thank you especially for the link. I am now sure my line is sound and would like you to remove any post discussing a specific move.

thank you,

g-man15

"as is" means that there are NUMEROUS places where a player can make the best move and be told that his answer isn't right. 

8.Nf5! shortens White's task. The move you have takes longer.

I tried to help you. 

I changed it, happy? now please remove any reference to the moves from your posts.

It is one of my life's goals to never learn how to do this.

I believe it was the third move - laterally inverted with different bishops - that the women's world champion couldn't solve. That knight move is the hardest to find. There is a usual sequence in books where black always tries to head back to  the opposite corner of the bishop's colour - BUT, a  defending player might try running to the wrong corner (as in puzzle) and hope the other player can't see the subtle move knight move.