Friday, June 28, 2013

Opposite colour bishops in the endgame: Part 3

Part 3: Sample endgame

In Part 3, we'll take a look at an endgame position featuring opposite-colour bishops, with White having a deficit of THREE pawns. Utilizing the ideas I have given in Parts 1 and 2, White can still draw the game despite his three-pawn deficit!

White to play and draw




1. Be8 Kc6

The other variations are as follows:

-1... b2 2. Bxd7+ Kc5 3. Bf5 Kc4 4. Kc2 Bc3 5. Bd3+ leads to the drawn position which we discussed in Part 2

-1... Kb4 2. Bxd7 Ka3 3. Bf5 Kb2 4. Bd3 leads to the similar drawn position

If you didn't understand what was happening above, go back and read Part 2:
http://nushsblackknights.blogspot.sg/2013/06/opposite-colour-bishops-in-endgame-part_26.html

2. Ke2 Bc1

Both 2... Kc7 3. Bf7 b2 4. Bg6 and 2...b2 3. Bg6 lead to a draw

3. Kd1 Bb2
4. Ke2 Bd4
5. Kd1 Kd6
6. Bf7 b2
7. Bg6! Kc5
8. Ke2! (D)

Position after 8. Ke2
Notice that if we take away the d-pawn, the position becomes similar to what we analyzed in Part 2: The White bishop checks the b-pawn's advance, and the White king can prevent the Black king from coming to the aid of either the b or e pawn. Once again, if you didn't understand what I just wrote, go back to read Part 2

Now, Black plays his last card: The d-pawn

8... d5
9. Bf5 Kb4
10. Bg6 Ka3
11. Bb1 Kb3
12. Kd1!

Position after 12. Kd1
Now with the White bishop checking the advance of the Black king, White can shuffle his king between d1 and e2

12... Kc3
13. Ke2 Bc5

To clear the way for the d pawn. But both White's bishop and king are controlling the d3 square

14. Kd1 d4
15. Ke2 Kb3
16. Kd3 (D)
1/2-1/2

Position after 16. Kd3
There isn't really much possibility for Black to push any of his pawns, since all the squares in front of them have been controlled by White. Even if Black were to try 16...Bb6 17. Ke2 18. Kc3, taking control of the d3 square, White can just keep his king on e2 and shuffle his bishop along the b1-h7 diagonal

And I say this again: Notice how Black's dark-squared bishop was unable to participate in the struggle because it was on the wrong-coloured squares. Had Black magically traded it for a light-squared bishop, the outcome would have been very different!

With that, I wrap up this series of articles on opposite-colour bishops in the endgame. Next time, we'll look at how bishops of opposite colours can also play a critical role in the middlegame




Links:
Part 1: http://nushsblackknights.blogspot.com/2013/06/opposite-colour-bishops-in-endgame-part.html
Part 2: http://nushsblackknights.blogspot.com/2013/06/opposite-colour-bishops-in-endgame-part_26.html

Sources:
"Modern Chess Strategy", Ludek Pachman

Wednesday, June 26, 2013

Opposite-colour bishops in the endgame: Part 2

Today is 26 June-- what would have been Day 1 of our Black Knights Camp 2013 had it not been for the unclear haze conditions.

While admittedly I am typing this in the middle of a rainstorm where there's not much of a haze, the instructions from MOE still hold, so we can't hold any sort of training sessions for the next three days. Apologies for that, guys

So let's get back to our topic which we left last week: Opposite-colour bishops in the endgame

Part 2: Endgames with a two pawn difference

While in the Part 1 we all saw that in endgames with opposite-colour bishops, a one-pawn advantage is often not enough to force a win. How about two pawn advantages?

This time, the outcome is not as clear, and it is certainly much harder for the weaker side to force a draw, because his bishop and king has to take care of two advancing pawns at the same time.

However, if the two pawns are close enough such that the enemy king and bishop are able to force a joint blockade, then the game will end in a draw:

Example 1: White to move
The d6 pawn is blockaded, and both bishops are on opposite-coloured squares. If White can trade off his f-pawn for Black's light-squared bishop, he will win the game since he will have an extra bishop to support the advance of his non-rook pawn. IF.


1. Kg6

Taking control of f7, and allowing the f-pawn to advance

1...Ba2

But Black is unperturbed

2. f5 Bb3
3. f6 Ke8!

The point! All of a sudden White realizes that he can't advance either pawn, as the Black king watches over the squares d7 and f7. Black can just continue with that bishop shuffle along the a2-g8 diagonal until he gets bored and accepts a draw.

Since he can no longer push the f-pawn (4. Kg7 Ba2 5. d7+ Kxd7 6. f7 Bxf7 7.Kxf7 leads to a draw), White marches his king over to the other side in the hope that he can utilize his other pawn to win:

4. Kf5 Ba2
5. Ke5 Bb3
6. Kd4 Ba2
7. Kc5 Kd7 (D)
1/2-1/2

Example 1: Position after 7...Kd7
So long as Black's bishop stays on the a2-g8 diagonal, and Black's king continues to blockade the d7 and f7 squares, there isn't really much chances for White to force a win

...

But now here's the interesting part: Should we magically drop two more pawns-- one on each side-- onto the chessboard, the outcome will be different!

Example 2: White to move
The setup is very much like Example 1. However, White can exploit the presence of the frozen b pawns to win:


1. Kg6 Ba2
2. f5 Bb3
3. f6 Ke8

The position is very much the same as what we encountered in Example 1, but White has a trick up his sleeve:

4. d7+! Kxd7
5. f7!! Bxf7+
6. Kxf7 (D)

Example 2: Position after 6. Kxf7
And unlike the previous example, it is now no longer a draw because of the two extra pawns!

6...Kc6
7. Ke6 Kc7
8. Kd5 Kb7
9. Kd6 Ka6
10. Bd4

Not 10. Kc6?? stalemate

10... Kb7
11. Kc5 Ka6
12. Be3

Again, not 12...Kc6?? stalemate

12...Kb7
13. Kxb5
1-0

The Black pawn falls, and White can win the resultant bishop + non-rook pawn endgame easily

From the Example 1, we saw that a two-pawn advantage in an opposite-coloured bishop endgame may not be enough to secure a victory, especially if the pawns are only one file apart. This is because the enemy king and bishop are able to establish an effective blockade over both pawns at the same time.

But from Example 2, we can also see that the defender's blockade may fall apart if there are too many areas for him to defend: In this case, the two extra pawns on the b-file stretched out his defenses too thin, and White was able to penetrate them and secure a victory

...

Moving on, we will look at a scenario where both pawns are two files apart. In such cases, the defender's task is more difficult as the king cannot establish a blockade over both pawns at the same time

However, should the weaker side's bishop be able to stop both pawns at the same time, he can use his king to prevent the enemy king from coming to the aid of his pawns:

Example 3: White to move
Both White's pawns are not able to advance on their own as the Black bishop controls the squares in front of them. White's bishop also isn't able to support the pawns as it is on the wrong-coloured squares

Thus, White will have to use his king to support the pawn advance. Let's take a look:


1. Kb5 Kd7
2. Ka6 Kc8

No chance! Black's king shadows the advance of White's king when he tries to come to the aid of the b-pawn. White cannot push the b-pawn (3. b7? Bxb7+) or the game will reach the theoretically drawn position which we discussed last week

Now, White's king moves back to aid his other pawn, but his opponent gives him no chance:

3. Kb5 Kd7
4. Kc4

Should White decide to move his bishop, Black can just mindlessly move his own bishop along the h1-a8 diagonal without giving up control of the squares in front of the pawns (e.g. 4. Ba3 Bh1 5. Bc5 Ba8 6. Bf8 Bh1 7. Ba3 Bg2 and nothing much has changed)

4... Ke6
5. Kd4

Attempting 6. e4. But Black continues to cover the square:

5... Kf5!
1/2-1/2

5. Kc5 Kd7 also does nothing much

Notice that while Black's king and bishop were able to work together to control the squares in front of the pawns, and shadow the movements of the enemy king, White's bishop could not do much to aid the pawns simply because it was on a wrong coloured square. Once again, this is how opposite-coloured bishops can help the weaker side!

...

How about distant pawns-- i.e. two pawns which are more than two files apart? Then the defender's task becomes EVEN more difficult, as his defenses are stretched even thinner. Take a look at the following example:

Example 4: Black to move
Black's position look's good enough: His bishop covers the b8 and f6 squares, and his king shadows the enemy king, preventing the f pawn from being pushed.

However, Black is in zugzwang! Any bishop move now will give up either the b8 or f6 square, and moving the king will allow the f-pawn to be pushed


1... Bb8

1... Kd8 also allows 2. f6, and White is more than happy to give up his pawn to win the enemy bishop: (2...Bxf6? 3. Kxf6 +-)

2. f6+ Kf8

2... Kd6 loses to 3. f7 Ke7 4. Kg7, and the f-pawn promotes

3. f7 Be5

Now White marches over the support the advance of his b8 pawn. Black's king is tied down blockading the f-pawn and cannot continue to shadow White

4. Kf5 Bh2
5. Ke6 Bg3

Black tries his best, moving his bishop back and forth on the h2-b8 diagonal. But without help from his king, it isn't enough to help him draw the game

6. Kd7 Bh2
7. Kc8 Bg3
8. b8=Q Bxb8
9. Kxb8
1-0

Winning the bishop and the game

...

So we can see that for pawns which are 3 or more files apart, it is very difficult for the weaker side to force a draw as he cannot stop both pawns advancing at the same time. But in the rare case where one of the pawns is a rook pawn of the wrong colour, then he CAN force a draw, by simplifying the position into a bishop + rook pawn of the wrong colour endgame!

Example 5: White to move
Black wins by trading off his bishop for the enemy g-pawn, simplifying the position into a theoretical draw


1. Kh6 Kc6
2. Kh7 Kb7
3. g7 Ka8
4. g8=Q+ Bxg8+
5. Kxg8 (D)
1/2-1/2

Example 5: Position after 5. Kxg8
In example 5, White forces a win because the resultant bishop + non-rook pawn endgame is a win for the stronger side. But here, the bishop does not control the same coloured square of the rook pawn: So if you know your endgame theory well, this should be a draw. You can play it out if you're not convinced (:

...

So from our analysis of the previous 5 examples, we can sum up the following for opposite-colour bishop endgames with a two-pawn difference:
  •  Positions where both pawns are only one file apart offer good drawing chances for the weaker side, since he can use his bishop + king to blockade both pawns at the same time. However, the presence of any additional pawn islands may stretch the defenses too thin, decreasing the chances of a draw
  • Positions where both pawns are two files apart are more difficult to draw. However, the weaker side still has chances if he is able to 1. Use his bishop to control the squares in front of both pawns at the same time  2. Use his king to shadow the movement of the opposing king
  • Positions where both pawns are three or more files apart offer few drawing chances, as it is difficult to blockade/shadow both pawns at the same time. However, in the rare case where one of the pawns is a rook pawn of the wrong colour, then the weaker side can simplify the position into a drawn endgame.
In Part 3, we will look at an interesting endgame position featuring bishops of opposite colour

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/06/opposite-colour-bishops-in-endgame-part.html

Sources:
"Silman's complete endgame guide", Jeremy Silman

Sunday, June 23, 2013

Removing the defender: Correspondence 2013

An instructive game with an interesting combination

Opponent vs Checkerboard 22
Correspondence 2013


1. e4 c5
2. f4

The Grand Prix Attack (1. e4 c5 2. f4) is an aggressive line of the Sicilian Defense, but it has declined in popularity due to Black's counterthrust 2...d5!? (a gambit). Nowadays a more common practice in this variation is to play 2. Nc3 first before 3. f4. You can find out more info about it here: http://www.thechessdrum.net/newsbriefs/2003/NB_GrandPrix.html

2...Nc6
3. Nf3 d6
4. Bb5 Bd7
5. Nc3 g6
6. d3 Bg7
7. O-O Qb6!?
8. Bxc6 (D)


Better would have been 8. Nd5!, which would have made Black's previous move look silly. Note that from here, Black cannot play 8...Qxb5?? because of 9. Nc7+!

8... Bxc6
9. Kh1 Nf6
10. Qe1 h5
11. e5 dxe5
12. Nxe5 Ng4
13. Nxc6

13. Nxg4? hxg4 opens up the h-file for Black's rook, giving him good attacking chances

13... Qxc6
14. Qe4 Bd4
15. Qxc6+ bxc6 (D)


Despite his weaker pawn structure (especially those doubled pawns on the queenside!), Black has more active pieces, and is threatening 16...Nf2+! White's best defense will be 16. Ne2, and now if Black insists upon 16...Nf2+?!, the game will continue 17. Kg2 Nxd3+ 18. Nxd4 Nxc1 19. Nxc6, where Black's isolated c-pawn will not do him any good

But now, White makes a mistake-- probably the decisive mistake of the game:

16. Ne4? (D)

Find the best variation for Black
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16...f5!
17. Ng5

17. c3 would have been a better alternative, but it still loses to 17...fxe4 18. cxd4 exd3 19. dxc5, when Black's passed pawn is difficult to deal with


17... Nf2+
18. Rxf2 Bxf2 (D)


By removing the defender on e4, Black carries out his threat and wins the exchange. Note that even if White were to defend with 18. Kg1, Black still secures the advantage with Nxd3+! 19. Kh1 Nf2+ 20. Kg1 Ne4+ 21. Kh1 Nxg5 +-. From here on, things generally went in Black's direction:

19. Bd2 Bd4
20. c3 Bf6
21. Ne6 Rb8
22. Bc1?

Passive, but there aren't really any better moves. Fritz suggests the alternative variation 22. b3 Kf7 23. Re1 c4

22... c4
23. dxc4 Kf7
24. Nd4 Bxd4
25. cxd4 Rhd8
26. d5 cxd5
27. cxd5 Rxd5
28. Be3 a6
29. b3 Rbd8 (D)
0-1

Position after 29. Rbd8
White played on for another 27 agonizing moves before he finally threw in the towel

Once again, all comments/alternative viewpoints are welcome!

Saturday, June 22, 2013

The double check

Let's go back to tactics today. Before we begin on today's topic, here are the answers to the puzzles from my earlier post (The discovered check)

http://nushsblackknights.blogspot.sg/2013/06/the-discovered-attack.html



And of course, the famous "Evergreen Game"



Take a look at the "Evergreen Game" again. Notice that while the discovered check was an intergral part of White's victory, Black couldn't block the discovered check 2. Bf5+ with 2...Bd5, because he was being attacked by the bishop and rook at the same time! This tactic is known as the double check, and that is what we'll be looking at today

Before you make a move, please double check that you've not fallen into a double check!
A normal check occurs one piece moves and attacks the enemy king. A double check occurs when one piece moves to attack the enemy king, at the same time uncovering a piece that also attacks the king. Hence the name "double" check.

Normally when a king is in check, there are usually four ways to escape the check:
  1. Capture the checking piece (if possible)
  2. Block the attack with another piece (only for long-range attacks)
  3. Move to a square that is not attacked by an enemy piece (if there is one)
  4. Resign because the above 3 methods don't work
But for a double check, the first two ways are no longer possible to help the attacked king escape-- you cannot use one piece to block a check from two directions, and you cannot capture two attacking pieces at the same time! So that leaves the 3rd and 4th ways as the only viable options in a double check, which often has painful consequences for the side under check.

Here's an example to show the power of the double check:

White to move and mate in 1
A first glance at the position and White looks like he's in trouble-- his position is being attacked by two minor pieces, and his Queen is also in hot soup. But using the powers of the double check, he turns the tables with...
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1. Bc6#

Checking the king with both the bishop and queen. Note that although both attacking pieces are hanging, the power of the double check renders them immune from capture. Neither can Black block with 1...Nd7 or 1...Be7, because there are two attacks coming from different directions! So that leaves the third option: To move to a safe square. But as we can see now there isn't one...

As you can see now, the double check is actually a special case-- and I can say, a buffed-up version-- of the discovered check, because the check by one piece unmasks a check by a second piece, which is almost always a bishop, queen or rook.

The following example shows the superiority of a double check compared to a normal discovered check:

Black to move and mate in 2
White just moved his knight from b3 to c5 (1. Nc5??), creating a discovered check and threatening to win the queen. Although this seems like a winning move, it is actually a blunder! Using the concept of double check, how will you punish White?
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1...Nc4+!
2. Kc1 Qh1#

Black turns the tables and forces a win in two moves. Once again, it is interesting how White can capture neither the Queen nor Knight due to the power of the double check!

The next example demonstrates how double checks can be combined with other tactics to secure an advantage for the attacking side

White to move

Combining the double check and the skewer, White can win the rooks:

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1. Bd8+! Kxd8 (1...Kd6 2. Rxg8 +-) 2. 2. Rxg8+ Kc7 3. Rxa8 +-

And when we return to the "Evergreen" Game, we can see how White manages to win with a spectacular combination of a decoy sacrifice, a discovered attack and a double check!

Anderssen - Dufresne
Berlin "Evergreen" 1852
White to move and mate in 4
1. Qxd7+! Kxd7 2. Bf5+ (NOT 2. Bb5+? Ke6!) Ke7 (2...Kc6 3. Bd7+) 3. Bd7+ Kd8 4. Bxe7# 1-0

So having seen enough examples, let's wrap up with some puzzles!

Black to move and mate in 3
Black to move
White to move and mate in 3
Have fun! (:

Source:
http://www.abcteach.com/documents/behavior-poster-double-check-your-work-39106
"1001 Chess Exercises for Beginners", Franco Masetti and Roberto Messa

Friday, June 21, 2013

Opposite-colour bishops in the endgame: Part 1

Good afternoon my fellow Black Knights, I believe y'all aware that our June Holiday Camp 2013 has been postponed due to the worsening haze situation.

Nothing we can really do about that, especially since it's an order from MOE

But that doesn't mean I'm gonna let y'all miss out on a whole week of training, which can be crucial since many of us are out of touch after the June vacation. So I'll expect both this blog and our FB group to be more active with puzzles, games and some simple lessons

Today, let's take a look at bishops of opposite colour

Heartbreaking, for our paths will never cross
Many chessplayers love toying with the term "Bishops of opposite colours"... many a time during a game analysis I would hear things like "Oh it's a draw, cos of the opposite colour bishops!" and stuff like that. But many of them don't really know the actual strategy behind such positions, so we'll look into that today.

In case you have no idea what the term means, "Bishops of opposite colours"...are literally what they mean: Opposing bishops on different coloured squares:

Bishops occupying opposite coloured squares
White's bishop occupies a dark-coloured square, while Black's bishop occupies a light-coloured square. These are what we term "bishops of opposite colours"

Notice that due to the bishop's unique properties-- that it can only control squares of a certain colour-- opposite colour bishops will never be able to cross paths with each other. This has some interesting repercussions, as we will see later

Positions with opposite-colour bishops typically fall into 2 categories:
  1. Middlegame positions. In such positions, the attacker has an advantage since the defender's bishop can't defend whatever his opposing counterpart attacks
  2. Endgame positions, where opposite-colour bishops can give the weaker side chances of drawing
We will look at middlegame positions another day. For now, I want to focus on how to play endgame positions with opposite colour bishops


Part 1: Endgames with a one-pawn difference

So why do so many chessplayers say that opposite-colour bishops lead to drawn endgames? These are a few reasons why:
  • The stronger side cannot force pawns over squares controlled by the enemy king and bishop, because there is no piece other than the king to give support to these pawns
  • A bishop cannot attack pawns posted on squares of the opposite colour

Let's take a look at the following position:

Example 1: This is a draw no matter whose turn it is
Black is down by a pawn, so going purely in terms of material he is the weaker side. Not helping is the fact that his king is too far away to stop the pawn from advancing to promotion.

However, Black still draws in this position, notwithstanding whose turn it is!

All he has to do is to keep his bishop on the a3-f8 diagonal, covering that crucial f8 square where the pawn will promote. White's bishop cannot do anything to support the pawn advance because his bishop covers the wrong coloured squares. Once the pawn promotes, Black is more than happy to exchange it off for his bishop, creating a drawn position.

See the following illustration if you're not convinced:


Self-explanatory. And if Black is in a suicidal mood he can leave the a3-f8 diagonal (1...Bc1?? 2. f8=Q!) and allow the pawn to promote.

And note: Had the White bishop been on d8 instead of e8 (thus creating bishops on the same coloured squares), it would have been able to support the pawn advance with 1. Kf6 Bb4 2. Be7!, and Black cannot stop the pawn from promoting. This is how much difference opposite-coloured bishops can make in the endgame!

...

That seemed simple enough. Now, let's take a step back and look at the next example:

Example 2: White to move
White has a better king position plus an extra pawn. However, Black can still exploit the opposite colour bishops to force a draw as follows:


1. f4 Ba1
2. f5 Bb2
3. g5 hxg5
4. hxg5

4. h5 g4 5. h6 gxh6 also draws for Black-- his bishop continues to guard the a1-h8 diagonal

4... Ba1
5. Kh7 Bb2
6. f6 gxf6

Or 6... Bxf6 7. gxf6 gxf6, also with a draw

7. g6 f5
8. Bxf5 (D)
1/2-1/2

Position after 8...Bxf5
Looks familiar? Yes-- similar to our previous example, there is no way the pawn can promote so long as the Black Bishop stays on the a1-h8 diagonal! Both sides can now shake hands and call it a draw.

Black's plan was simple-- keep his bishop on the a1-h8 diagonal, trade off the pawns when required, before trading off his bishop for the final pawn. He has no fear from the White bishop, who has no power to interfere with his operations.

And once again, had the White bishop been on e3 instead of d3, it would have been able to support the pawn advance easily (e.g. 1. h5 Ba1 2. Bxh6! gxh6 3. Kxh6 and Black has no power to stop the 3 connected passed pawns), and the game would have ended in White's favour

...

And now for the next example:

Example 3: Black's pawns aren't going anywhere
Black has a passed pawn but it is being blockaded by the White king, and it cannot be chased away by the Black bishop

Black's dark-squared bishop also cannot attack the kingside pawns, which are set on opposite colours. True that the Black king may be able to move in and help, but the pawns are being guarded by the White light-squared bishop

By keeping the blockade on e7, and fixing his bishop on the h1-a8 diagonal, White effectively blockades all of the enemy pawns: The e3 pawn isn't going anywhere, and neither are Black's kingside pawns. The h3 pawn is being guarded by his counterpart on g2, which is in turn guarded by the White light-squared bishop. So once again, by moving his bishop along the h1-a8 diagonal, White forces a draw in this position.

In fact, Black probably won't be able to win no matter how many more dark-squared bishops we give him. What he badly needs is a light-squared bishop...which he doesn't have!

Six zombies ain' worth a light-squared cleric
So to wrap up Part 1...we can see by now that when there are relatively few pieces on the board, a position with opposite-coloured bishops contains good drawing chances for the weaker side.This is especially obvious in simplified positions like the first example which I have given.

So next time you find yourself with a material disadvantage, a good way of staving off defeat will be to trade off your pieces such that you end up with opposite-coloured bishops in the endgame. From there, you can help yourself with a few tips:
  • You can prevent promotion of an enemy pawn using the "diagonal" tactic described in our last 3 examples
  • Post your pawns on squares that cannot be controlled by the enemy bishop
  • When blockading with a piece, try to blockade on a square that cannot be controlled by the enemy bishop
In positions with a one-pawn difference, such tips are usually enough to force a draw.

In Part 2, we will discuss on endgame positions with 2 pawns difference and above...and then, the idea of opposite-coloured bishops won't be as simple what we see now...

Sources:
http://www.lushquotes.com/tags/bishops/
"Silman's complete endgame course", Jeremy Silman
"Modern Chess Strategy", Ludek Pachman

Monday, June 17, 2013

The discovered attack

Before we move on to our main topic, let's take a look at the puzzle I gave y'all the other day:

Keres - Spassky
Gothenburg 1955
Find the best move for White
The answer, as many of you should know by now...
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1. Qxg7! 0-1

Black resigned due to the variation 1...Kxg7 2. Nxd7+ Kg8 3. Nf6+ Kg7 4. Nd5+ Kg8 5. Nxc7

So this puzzle can be solved using the decoy sacrifice technique, which y'all have read about. But it also involves another tactical weapon: The discovered check of the White bishop on the Black king with 2. Nxd7+. And that's what we'll be talking about today.


A discovered attack occurs when one piece moves to attack another piece, at the same time unmasking an attack by a 2nd piece. This 2nd piece is almost always a rook, bishop or queen, due to their long range capabilities.

But words alone won't explain this good enough, so it's always best to show examples:

Find the best move for White

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1. Be7! +-

The bishop attacks the rook on e7...at the same time unmasking an attack by the White rook on the Black queen! Black must now make a painful decision between losing either his queen or his rook. This is the discovered attack.

A discovered check occurs when the piece being attacked is none other than His Majesty. Take a look at the following example:

Find the best move for White
Over here the discovered check does not manifest straightaway. But after a preliminary sacrifice...
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1. Rxg6+! fxg6 (1...Kh8 2. Qxh5+ Bh6 3. Qxh6#) 2. d6+!

And with the discovered check White wins a Queen

The discovered attack is probably one of the most commonly occurring tactical weapons (after the fork and pin) because it is an easy threat to set up. For example, consider this position after the moves 1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. cxd5 Nxd5 5. e4 Nxc3 6. bxc3 Bg7 7. Bc4 O-O 8. Nf3 c5 9. O-O Nc6 10. Be3 Qc7!?

Position after 10. Qc7!?
With his last move, Black creates a potential discovered attack on the hanging bishop on c4, and White will have to stay alert for this threat. For example, if after 11. Rb1 cxd4 and White decides to be suicidal by playing 12. Bxd4??, then Black wins the c4 bishop with 12. Nxd4!

I myself have encountered the discovered attack several times throughout my chess career, both as the attacker...

Opponent - Checkerboard 5
Thomson CC Chess Challenge 2013, Round 7
Black to move
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1...Ndxe5! Winning the pawn with a discovered attack on the White Queen

...and the victim.

Checkerboard 5 - Opponent
Thomson CC Chess Challenge 2013, Round 6
Black to move
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1...Rxf4+! Winning the Queen

Should have seen enough examples by now? Let's wrap up with some puzzles!

Find the best move for White

Black to move and mate in 3
Lastly, here's a position from the famous "Evergreen Game"...using the concept of discovered check, find the winning combination for White!

Anderssen - Dufresne
Berlin "Evergreen" 1852
White to move and mate in 4

Sources:
forum.yugiohcardmaker.net

Friday, June 14, 2013

Story of an attacking player: Mikhail Tal



Yesterday the 8th Tal Memorial opened with a spectacular start, producing 3 decisive games. Carlsen defeated Kramnik convincingly with the White pieces, while Anand crashed to a shock defeat at the hands of Fabio Caruna

You can view their games here: http://www.chess.com/news/tal-memorial-opens-with-wins-for-caruana-carlsen-and-mamedyarov-7770

So while everyone is getting hyped up over all those exciting games, let's have a short insight into our protagonist so that you can appreciate him better. He is no other than the person which this tournament is named after: Mikhail Tal


Nicknamed the "Magician from Riga", Mikhail Tal was one of the greatest attacking players of all time, and was the World Chess Champion from 1960 to 1961. He was known for his brilliant combinations and daring sacrifices.

Biography

Tal was born in 1936 at Riga, Latvia, into a Jewish family. He learnt to play chess by watching games being played in his father's waiting room. Soon after he joined the chess club in the Young Pioneers at Riga Palace, but at that time his playing skills were still not considered exceptional

Later on in 1949 he studied under the leading Latvian chessplayer Alexander Koblencs, from then which his playing style began to improve rapidly. He won the Latvian Championship in 1953, winning the title of Candidate Master. Tal then went on to become the Soviet Chess Champion in 1957, becoming the youngest player to win it at the age of 20. It was then that FIDE awarded him his Grandmaster title

Tal went on to play among the world elite, competing in international tournaments alongside leading players such as Paul Keres, Tigran Petrosian and Bobby Fischer. He won the 1959 Yugoslav Candidates Tournament, qualifying him to face Mikhail Botvinnik (then World Chess Champion) in the 1960 World Chess Championship

Tal (seated left) facing off against Botvinnik in the 1960 World Chess Championship
Tal defeated Botvinnik with a convincing score of 6 wins, 2 losses and 13 draws. As such, at the age of 23, Tal became the youngest ever world champion (this record would be broken by Kasparov).

Botvinnik later returned to defeat Tal in the 1961 World Chess Championship. During the period between matches Botvinnik had carefully analyzed his opponent's playing style, avoiding wild tactical games (which were Tal's hunting grounds) and instead went for slow maneuvers or endgames.

Despite his defeat, Tal remained active in his chess career, winning several international tournaments such as the 1961 Bled supertournament and the 1979 Montreal tournament. He was also part of the Soviet Team in several Chess Olympiads, winning several team and individual medals.

Although a strong chess player, Tal suffered from ill health throughout his life. This was further aggravated by his penchant for smoking and drinking. He died in a Moscow hospital in 1992 due to a haemorrhage in his oesophagus.

Playing style and chess games

As stated earlier, Tal was one of the greatest attacking players of all time, and was not afraid to sacrifice material in order to seize the initiative. This created complicated positions which many of his opponents found very difficult to handle, although post-game analysis eventually found flaws in some of his methods (see the 1961 Botvinnik-Tal game below). One of his quotes pretty much explains how he managed to win so many of his games:

"Later, I began to succeed in decisive games. Perhaps because I realized a very simple truth: not only was I worried, but so was my opponent"
-Mikhail Tal

To put it in more familiar terms, he was very adept at "scamming" his opponent.

Although several chessplayers such as Vasily Smyslov scorned his playing style and called them nothing more than a bag of "tricks", Tal experienced much success against many high level grandmasters with his trademark aggression. In fact, the book Modern Chess Brilliancies (2004) included more of Tal's games than that of any other player.

Having highlighted Tal's aggressive play so many times, it'll be more convincing if I show some examples. Well, here goes:

Mikhail Tal vs Vasily Smyslov
1959 Yugoslav Candidates Tournament


Black resigned as the variation 41...Rg8 42. Rf8 Rd8 43. Bxg8 doesn't leave him with much hope

Another interesting game will be the following, where Tal uses the classic Bxh2 sacrifice to hunt down his opponent's king:

Boris Spassky vs Mikhail Tal
Montreal 1979


White resigned in view of the variation 23. Re1 Rh1+ 24. Kxh1 Qh4+ 25. Kg1 Qh2+ 26. Kf1 Qxg2#

Maybe Spassky should have been more prudent and declined the sacrifice with 21. Kf1

Lastly, here's a brilliancy game played by Tal in 1967:

Istvan Bilek vs Mikhail Tal
Moscow 1967


Tal Memorial

To honour Tal's memory, the Tal Memorial is held annually in Moscow since 2006. This year, the tournament's participants include top players such as Magnus Carlsen, Vladimir Kramnik, Anand Viswanathan and Sergey Karjakin. Before the event, a warm-up blitz tournament was used to decide the player lots for the actual tournament. Hikaru Nakamura won the blitz event with a score of 7 out of 9 points

The report after each round will be posted up on the chess.com website from 13 June to 22 June 2013. So let's look forward to an exciting week of games! (:

Sources:
http://www.chess.com/news/tal-memorial-opens-with-wins-for-caruana-carlsen-and-mamedyarov-7770
http://www.chessintranslation.com/2010/11/mikhail-tal-and-contemporary-chess/
http://chessreview.co.uk/tournaments/1960-69/1960-world-championship/
http://en.wikipedia.org/wiki/Mikhail_Tal
"How to calculate Chess Tactics" by Valeri Beim