Why are endgames so hard to master? That's because in the opening and middlegame play, usually, you do not get punished as severely when choosing sub-optimal moves.
In the endgame, there is no such thing as sub-optimal moves. Usually, the move has to be technically accurate and correct. The margins between winning, drawing and losing are on a knife's edge. Choosing the wrong strategy results in disastrous consequences.
For a long time, I've been trying to get my head around working on endgames (with many thanks to Karsten Mueller for his terrific tomes and DVDs). The problem with endgames are that you need to know what you're doing and you need to do it right every time.
Who are the greatest endgame masters?
On the top of my head, 3 famous names come to mind : there's of course the well known Cuban champion Jose Raul Capablanca, the inimitable singer and gentlemanly champion Vasily Smyslov and the monster that is Viktor Korchnoi.
If you want to learn endgames, choosing any books from these players with actual games from these masters and you are very unlikely to go wrong.
In addition, there are also many great endgame books eg. Averbakh, Nunn, Dvoresky, Fine.
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As an example, take the following position (1st diagram on left):
This game arose out of a Sicilian Najdorf. I am White and it is White's turn to play.
Over here, Black activated the Knight to gain some activity with 27.... Nc5.
The question is: should you trade the dark-squared bishop for the Knight?
In this case, I took my time to carefully calculate.
And the answer is a resounding yes. Why?
All of black's pawns are on dark squares, surely it is more advantageous to have a dark squared-bishop so you can attack the pawns, no?
Not so in this case, in this game, I calculated that in order for Black to activate the bishop, his only route is via h6 and the only pawn he can attack is h4. In order to get around h4, he needs to manouevre his bishop h4-e3 or d2. The Knight is a fine blockading piece, I am going to move my Knight around to occupy e4.
28. Bxc5 dxc5
Now I manoeuvre Knight to the perfect outpost on e4 where it attacks b5 and f6 Now Black must spend the rest of its time defending and can only watch while I carry out my plans.
29. Nd2 a5
30. Ne4 Kf7
With this done, I now want to close off the a-file to stop any potential counterplay. I can take my time to do this because Black isn't going anywhere. Remember that it is important that you do not hurry in the endgame.
31. b3 Kg7
32. Kf2 Kf7
33. Kf3 Kg7
34. Ke3 Kf7
35. Kd3 Be7
36. Kc2 Kg7
37. Kb2 Kf7
38. a3 Kg7
39. axb4 axb4
now that the a-file is closed. I can carry out my plan.
40. Kc2 Kf7
41. Kd3 Bf8 (see 2nd diagram on left)
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42. d6! Bxd6 (forced) if the Pawn is not taken, then d7 is coming followed by either Nxf6 or Nd6+!! (the Knight cannot be taken of course else the d-pawn queens) and the Black King cannot move around to attack the d7 pawn. Now all I need to do is move my King to attack the queenside pawns via the hole e4-d5 and White wins.
43. Nxd6+ Ke7
44. Ne4 Kd7
45. Nxf6+ Kd6 Black resigns 1-0