Friday, February 08, 2013

Decomposing an endgame

The position from the previous post proves to be a bit too difficult for me. That's why I try first to get some insight in a simplified version of the position. We already know that the underlying pawnending is winning. How about the light pieces only?

White to move.
When the computer plays this game against itself, it is winning for white time and again. Sofar I have identified the following weapons for white:
  • Threat of promotion of the a or b pawn.
  • Threat against the c pawn. Actually I haven't seen that this played a big role, so it seems to be more theoretical than practical.
  • Kingwalk to the kingside during the time black needs to get rid of the outside passer.
  • Scattering the kingside pawns with a pawn sac. Eating pawns during the time black needs to get rid of the outside passer. If white puts his pawns on the dark squares as precaution, they are immune for the bishop.
So the general idea is: threathen promotion at the queenside.
Gobble up pawns at the kingside while black rids himself of the threat at the queenside.  Attack two weaknesses, so to speak.



3 comments:

Temposchlucker said...

Both Mr. Z and I managed to win this position against different engines. The next step is to try the same with the rooks on the board in stead of the minor pieces.

Munich said...

My knowledge about how to win this kind of endgame, and I hope this really helps you:
If you have the knight and you are a pawn up, the general rule is:
keep your pawns behind. Improve first your position, get the kings early into blockading each other in the middle (or close to where your passer is).

(If you have the bishop and are a pawn up, you can shift your passed pawn forward, guarded by your bishop. White needs to keep either his short ranged knight bound to stop that pawn or his king. In case white is trying to win the pawn by taking with his knight and guarded by his king, you trade of pieces. Since you pushed your pawn forward early, that means that whites king position is now likely to be far away from where the action is, while your own black king will win the pawn ending due to his better position.)

--> according to this general knowledge (guidance), the very best move in my opinion is 1.Kf1, which activates the white king. The white knight is for the moment placed good enough. If we dont move the king first, the black bishop might be able to delay the walk of the white king with 1...Bc4.
After you improved your kings-position it might then be time to move your knight and then push the f-pawn to f3 to make sure it cant be attacked. But if this is not neccessary, the improvement of your kings position is more important. But I feel it is pretty soon neccessary to at least move the knight soon in order not to lose the f-pawn. My guidance says nothing about that. It just says: "if possible, improve your kings-position first and keep pawn moves for later".

According to this guidance rule, the good looking b2-b4 (blocking the c-pawn) would be a mistake, because you must not push your pawns early if you have the knight.

One different mini-guidance rule is good to know, too: the knight is best places behind his pawns. With a pawn on for instance b4 the best place for the knight would be c3. Look at the squares the pawn b4 and the knight c3 are covering together. It is a huge wall that an opponent king cant overcome, so you will have your own king free to do a different task.

Munich said...

My knowledge about how to win this kind of endgame, and I hope this really helps you:
If you have the knight and you are a pawn up, the general rule is:
keep your pawns behind. Improve first your position, get the kings early into blockading each other in the middle (or close to where your passer is).

(If you have the bishop and are a pawn up, you can shift your passed pawn forward, guarded by your bishop. White needs to keep either his short ranged knight bound to stop that pawn or his king. In case white is trying to win the pawn by taking with his knight and guarded by his king, you trade of pieces. Since you pushed your pawn forward early, that means that whites king position is now likely to be far away from where the action is, while your own black king will win the pawn ending due to his better position.)

--> according to this general knowledge (guidance), the very best move in my opinion is 1.Kf1, which activates the white king. The white knight is for the moment placed good enough. If we dont move the king first, the black bishop might be able to delay the walk of the white king with 1...Bc4.
After you improved your kings-position it might then be time to move your knight and then push the f-pawn to f3 to make sure it cant be attacked. But if this is not neccessary, the improvement of your kings position is more important. But I feel it is pretty soon neccessary to at least move the knight soon in order not to lose the f-pawn. My guidance says nothing about that. It just says: "if possible, improve your kings-position first and keep pawn moves for later".

According to this guidance rule, the good looking b2-b4 (blocking the c-pawn) would be a mistake, because you must not push your pawns early if you have the knight.

One different mini-guidance rule is good to know, too: the knight is best places behind his pawns. With a pawn on for instance b4 the best place for the knight would be c3. Look at the squares the pawn b4 and the knight c3 are covering together. It is a huge wall that an opponent king cant overcome, so you will have your own king free to do a different task.