Saturday, August 27, 2016

Term 3 Tactical Presents: Part 3

Here's a few more puzzles before Term 3 comes to a close!



Have fun!

Monday, August 22, 2016

A World Championship "Prequel": Bilbao 2016

Today, we will focus on a game between the two upcoming candidates for the World Chess Championship: Carlsen and Karjakin. Their recent encounter in Bilbao was the first of many prior to November.

In Round 3 of Bilbao 2016, Carlsen defeated Karjakin after the latter weakened his kingside and underestimated a powerful attack. Let us see how the Norwegian grandmaster executes his plans in the game.

"I should let him win, then wipe him out in November"

Carlsen. Magnus vs Karjakin, Sergei
Bilbao Masters 2016

1. e4 c5
2. Nf3 d6
3. c3 Nf6
4. Be2 g6

4... Nxe4 5. Qa4+ wins the knight.

5. O-O Bg7
6. Bb5+ Nc6
7. d4 Qb6

Black still can't take on d5: 7... Nxe4 8. d5 a6 9. Ba4 b5 10. Bc2 either knight will be lost.

8. Ba4 cxd4
9. cxd4 O-O
10. d5 Nb8

To relocate the knight via Nd7-Ne5-Nc4, but better could have been achieved via Na5: 10... Na5 11. Nc3 Nc4 a faster route to c4.

11. Nc3 Bg4
12. h3 Bxf3
13. Qxf3 Nbd7

Black has given up his light squared bishop to weaken his opponent's control over the dark squares. Now the e5 square is a good spot for his knight.

14. Rb1 Rfc8 (D)

Position after 14... Rfc8

Black plans to use the c-file and his control of the dark squares to help him on the queenside. The g7 bishop can be a very strong supporter.

15. Bc2 Ne5
16. Qe2 Nfd7
17. Bg5

Creating complications for Black. Also good is} 17. Kh1 followed by f4 kicking the knight and starting a kingside attack.

17... h6

17... Bf6 18. Bxf6 Nxf6 was another possibility, but Karjakin wouldn't be very willing to part with his dark squared bishop.

18. Bh4

18. Bxe7 g5 trapping the bishop with unecessary complications which Carlsen wishes to avoid.

18... g5!? (D)

Position after 18... g5

Karjakin plans to meet a future f4 push with a pawn exchange. The problem with his past two moves, however, are that they weaken the light squares around his kingside. This will turn out to be his undoing later on.

19. Bg3 Qa6
20. Qd1

Carlsen doesn't want to trade queens since he is preparing to attack the kingside.

20... Rc4

A suggested alternative was 20... Nc4 which opens the diagonal for the bishop. After 21. Bd3 Nc5 22. Be2 b5 the resulting position is unclear. While Black is able to attack first, White still has the threat of f4 up his sleeve.

21. Kh1

A bit of prophylaxis before starting the attack.

21... Rac8
22. f4 gxf4
23. Bxf4 (D)

Position after 23. Bxf4

Note Black's kingside is becoming weaker.

23... Qb6

Can Black find counterplay on the other wing? I thought 23... b5 would have been more active; 24. Bb3 (24. Qh5? b4 winning a piece.) 24... R4c5 25. Qh5 Nf6 26. Qf5 Nc4 where the attack on opposite wings makes this a true, hot-blooded fight.

24. Qh5 Nf6
25. Qf5

Emphasizing White's strength around the light squares. How can Black evict the queen?

25... Qd8
26. Bb3

White wouldn't want 26. Bxe5 dxe5 27. Qxe5 Nxe4 where the discovered attack on his queen leads to difficulties.

26... Rd4

Black keeps the rook on the 4th rank to put pressure on e4.

27. Bxe5!

Eliminating Black's most active piece.

27... dxe5
28. Rbd1 Qd7
29. Qf3 Rb4?

I didn't like this move, I thought Black was better off trading rooks to remove some of White's attacking strength: 29... Rxd1 30. Rxd1 b5 slowing down the attack and fighting back on the queenside.

30. Rd2 Rf8
31. g4! (D)

Position after 31. g4

Carlsen goes all out. His rooks are ready to swing to the g-file.

31... a5
32. Rg2 Nh7

Temporarily stopping g5, but White simply continues...

3. h4 Rb6

Not a nice prospect but Black needs to muster every piece to defend.

34. g5 Kh8
35. Rfg1 f5?

This only hastens the defeat. 35... Rg6 would have held out longer, White can't push either pawn so Carlsen will need to find a longer method, maybe 36. Ne2 bringing in more attackers. (36. gxh6 Bxh6 37. Rxg6 fxg6 or 36. h5? Nxg5 both variations land White's queen in trouble.)

36. Qh3! Rb4
37. gxh6 Bxh6
38. Qg3

Threatening mate on g8. The game is as good as over.

38... Nf6
39. Qg6 Ng4
40. Rxg4 (D)
1-0

Position after 40. Rxg4

40. Rxg4 fxg4 41. Qxh6+ Kg8 42. Qg6+ Kh8 43. Qh5+ Kg8 44. Rxg4+ Black must lose the queen to avoid mate.

Looks like Karjakin will have a lot to prepare for in the upcoming World Championship!

Sources:
https://www.chess.com/news/view/carlsen-beats-karjakin-surges-to-clear-first-in-bilbao-5244
http://thechessworld.com/learn/annotated-games/49-famous-games/855-3-best-games-of-the-week-37-
https://www.youtube.com/watch?v=g6qapvUoaiM
https://www.youtube.com/watch?v=UZIFRcZ-vh8

Wednesday, August 17, 2016

Learning the Bishop-Knight Checkmate

As promised some time ago, we will touch on the elusive Bishop-Knight Checkmate. While it rarely occurs in gameplay, it might someday still save you a crucial half-point. Besides, it's not bad showing off to your (non chessplaying) friends how to execute the checkmate, wouldn't it?

This checkmate is easy to learn, but difficult to master. The reason it is so tricky is because unlike basic mates, it is tough building a "wall" that forces the enemy king to the corner. A queen, rook or two bishops can cut off entire files. With a bishop and knight, it isn't so easy. You need strong understanding of king opposition, square visualization, and even silent moves to carry out the job.

Oh, and did I mention that that you need to abide by FIDE's 50-move rule? So every move counts.

But like all basic mates, the fundamentals are the same. It's about trapping the enemy king and pushing him to the side of the board.

Here are a few key points to note:

  1. You can only force mate in a corner that's the same coloured square as your bishop. For example, if you have a light-squared bishop, you need to deliver the mate on a8 or h1.
  2. If your opponent is smart, he will tuck his king into the wrong-coloured corner since mate cannot be forced there. You must know how to pull him out from that corner towards the correct-coloured one.
  3. We will use a special tool called Deletang's Triangles: Successive shrinking triangles that push the enemy king towards the corner. Building them requires a team effort by king, bishop and knight.

Deletang's Triangles

The 3 triangles are constructed as follows:

Deletang's Large Triangle

Deletang's Large Triangle

In the Large Triangle, all White's three pieces cooperate to build a "wall". The pieces are located on their ideal squares:

  • The bishop positioned on the hypotenuse of the triangle, one square away from the corner. In the above diagram that means either b3 or f7
  • The knight located one square away on the same rank/file, in this case d3 or f5
  • The king located on the opposite corner of the triangle, where he will use the technique of opposition to confine the enemy king.

Why are these ideal squares? In the diagram, the bishop covers all the light squares along the triangle's border, while the king and knight fill up the dark squares. Notice Black's king cannot even touch White's minor pieces.

Here is an example of Deletang's Large Triangle from Black's perspective, along the dark squares:

Delatang's Large Triangle from Black's perspective

Deletang's Medium Triangle

Deletang's Medium Triangle

In the medium triangle the ideal squares for the minor pieces are located at the same points along the triangle. Once again Black's king cannot escape his prison.

Deletang's Small Triangle

Deletang's Small Triangle

The Black king is confined to two squares in the correct-coloured corner. As usual the bishop cuts off the diagonal, but this time the knight is located on either b4 or e7 to deliver the mating blow. There is a simple forced mate: 1. Bc7+ Ka7 2. Nc6#

If Black's king on a7 instead of a8 White still can checkmate: 1. Nc6+ Ka8 2. Bb7#

To shrink from one triangle to the next, you have to force the opponent's king to move inwards, before re-positioning the bishop to the diagonal of the smaller triangle.


The broad idea

The general plan to deliver the mate consists of 3 steps:

  1. Force the opposing king from the centre of the board to one of the corners.
    • If he goes to the right-coloured corner, jump straight to Step 2 and form the triangles.
    • If he goes to the wrong-coloured corner, flush him our of there towards the correct corners.
  2. Use Deletang's Triangles to trap the king and push him towards the correct corner
  3. Once the small triangle is formed, deliver the checkmate.

Take a look at the following game for a better illustration. As you look through, try to visualize the squares controlled by White to see how the "wall" is build.


Image from memegenerator.net

It looks simple at first glance, but reality is far from that. As stated earlier, this checkmate is easy to learn but difficult to master. The only way to gain a firm grasp is to keep practicing until it is ingrained in your head.

Use the following link to hone your skills in the bishop-knight checkmate. Start by getting the technique right first, regardless of how many moves it takes. Once you are familiar, try to do it within 50 moves. It is difficult at first, but over time you will get well-versed with the concepts.

Monday, August 15, 2016

Vachier-Lagrave vs Anand, Sinquefeld 2016

The Sinquefeld Cup has drawn to a close, with GM Wesley So winning his first ever super-tournament. However, today we will be looking back at a game from Round 2, between Anand and Vachier-Lagrave.

Anand (left) vs Vachier-Lagrave (Image from chess.com)

In this crazy game, MVL had a prospective attack after Anand misplayed the opening. Then, the Frenchman played a miscalculated sacrifice that turned the tables and gave his opponent the better endgame. Anand's victory put an end to Vachier-Lagrave's unbeaten streak in 2016.

Vachier-Lagrave, Maxime vs Anand, Viswanathan
Sinquefeld Cup 2016, Round 2

1. e4 c6
2. Nf3 d5
3. Nc3 Nf6
4. e5 Ne4
5. Ne2

5. Nxe4 dxe4 White must lose tempo moving the knight.

5... Qb6
6. d4 e6
7. Nfg1?!

Surprising to see such a move in high-level play. While the motive is to play f3 kicking the knight, there is a better alternative suggested by Youtube user thechesswebsite: 7. Ng3 and if Black takes 7... Nxg3 8. hxg3 White is not worse off at all.

7... f6
8. f3 Ng5
9. exf6 gxf6
10. f4?!

The knight just goes back to e4.

10... Ne4
11. Ng3 Bd7
12. Nxe4 dxe4
13. c3 (D)

Position after 13. c3

Strengthening d4 and denying Black's bishop the b4 square. Here, White has a better pawn structure but is far behind in development.

13... Na6

Preparing to castle queenside. GM Robert Hess suggests a better line: 13... c5 (Attacking the centre to exploit White's lag in development.) 14. d5 Na6 15. Qh5+ Kd8 16. dxe6 Qxe6 17. Ne2 Bd6

14. Qh5+

Development with threat helps White regain his lost tempo.

14... Kd8
15. Bc4 Kc7
16. a4

Since Black is running his king to the queenside, White creates trouble on that wing. The threat is 17. a5 trapping the queen.

16... c5

Hitting the centre and giving his own queen some space.

17. Ne2 Rd8
18. Be3 (D)

Position after 18. Be3

Things are looking dangerous for Anand. Just a few moments ago MVL was the one behind in development, but he has fought back. Although White has yet to castle, his king is definitely less exposed than Black's.

18. f5 is strong; cxd4 19. fxe6 dxc3 20. Nxc3 Bxe6 21. Bf4+ White has unleashed almost all his pieces
into a strong attack.

18... f5

A good defensive resource, protecting e4 and cutting White's queen off from the queenside.

18... Qxb2? 19. O-O the threat is Rfb1 trapping the queen; Black must lose even more tempo to parry that.

19. O-O Kb8
20. Qf7 Nc7
21. a5

Black mighty have brought his king to safety but White has prepared a good queenside attack.

21... Qc6

Once again 21... Qxb2? 22. Rfb1 traps the queen.

22. Qf6 Bd6
23. dxc5 Bxc5
24. Nd4

We see tension building up around e6.

24... Qd6
25. b4 Qe7
26. Qh6 Bd6 (D)

Position after 26... Bd6

"I didn't see a win against ... Bd6, so I'm just going to hold my breath and play it"- Anand

27. Rad1

27. a6 was also a good move, weakening the light squares around Black's queenside after b6

27... Rhf8

Preparing a rook lift to f6 driving away the queen.

28. Bf2

The danger is Bh4 winning an exchange.

28... Rf6
29. Qh4

29. Qh3 was better since White still has the possibility of Bh4

29... Nd5 (D)

Position after 29... Nd5

30. Nxe6?

"Losing on the spot' - GM Robert Hess. White miscalculates an exchange sacrifice. He would have been alright after 30. Bxd5 exd5 31. Qh3 with Bh4 still being a powerful threat.

30... Bxe6
31. Bxd5 e3!

This powerful zwischenzug was what MVL missed. His bishop is forced into a discovered attack.

31... Bxd5 32. Rxd5 e3 33. Bg3 was probably what MVL had in mind, since he is now up a pawn. Still, Black's passed pawn is a force to be reckoned with.

32. Bxe3

32. Bg3? e2 winning.

32... Bxd5

Now White cannot capture on d5 since his bishop is under attack. He is forced to enter the endgame down the exchange.

33. Bxa7+ Kxa7
34. Qf2+ Bc5! (D)

Position after 34... Bc5

Forcing a queen exchange. With more pieces off the board, Black's material advantage is significant.

35. Qxc5+ Qxc5+
36. bxc5 Rd7
37. Rfe1 h6
38. Kf2 Kb8

38... Ka6 {centralizing the king in the endgame was better.

39. c4 Bc6
40. Rxd7 Bxd7
41. Rb1 Ra6
42. Rb6 Rxa5
43. Rxh6 Rxc5
44. h4 Rxc4
45. g3 Kc7
46. h5 b5 (D)
0-1

Position after 46... h5

46... b5 47. Ra6 b4 48. h6 b3 49. h7 Rc2+! The key move; Black skewers the king to the h2 square. 50. Kf3 (50. Kg1 b2 with mate to follow.) 50... Rh2 picking up the pawn and winning.

Sources:
https://www.youtube.com/watch?v=zJxBUyfpFL8
https://www.chess.com/news/view/anand-ends-vachier-lagrave-s-streak-leads-sinquefield-with-three-others-7900

Monday, August 8, 2016

National Day Tactical Challenge

A good holiday can't go without good puzzles:






It's the circle of life...

Image from imgur.com


Sources:
Chess.com Tactics Trainer
http://imgur.com/0GqqVAR