Tuesday, 19 May 2015

Teaching Kids - Pin - Part 2

Before proceeding, I recommend you to go through part -1.

Following to discussion on part-1, let's move on getting benefits out of pin. Basically there are four ways to get benefited from Pin.

1. Increase nos of attack on pinned piece.

Knight on c6 is pinned so you can simply win the piece by playing pawn d4 to d5. This method works very well with absolute pin though you can do the same with relative pin too. But with relative pin, pinned piece is not completely paralyzed.

2. Illusion

In this position if there is a no pawn h7, black can be checkmated with Rh8#. But you can break the defence with 1. Qxg6!! as 1... fxg6 is not possible due to the Pin (Bishop on b3 is pinning the f7 pawn). Therefore pawn on f7 is defending g6 is only illusion.

3. Changing pinned piece

Here 1. f6 (increasing nos of attack on pinned piece is not the proper one because of 1...g6. But it is often good idea to change the pinned piece in order to break the defence. In this case
1. Bxg7!! - Bxg7
2. f6 wins the queen otherwise it is checkmate.

4. Gaining a tempo

White is pawn plus but exchanging everything wouldn't solve the issue, for example
1. Bxf6 - Rxf6
2. Rxf6 - Kxf6
3. b5 - Ke6
4. b6 - Kd6
5. b7 - Kc7 = and Black king is in time to catch the pawn.

But what happned if white is a tempo ahead in the same position (Pawn is on b5 instead of b4). Obvious white can win the game by swap off all pieces. White can win this position with
1. Rxf6!! - Rxf6 (Now rook is pinned therefore white is able to gain a move with b4)
2. b4 -  Kf7
3. Bxf6 - Kxf6
4. b6 - Ke6
5. b7 - Kd7
6. b8=Q wins the game.

We will discuss a classical game on next article in order to explain "if & but" of pin.

Monday, 18 May 2015

Teaching Pin to Kids

Pinning and winning.

In chess, a pin is a situation brought on by an attacking piece in which a defending piece cannot move without exposing a more valuable defending piece on its other side to capture by the attacking piece.
Source: Wikipedia

Looks complicated, let me explain it with the help of following example

On your right hand side
- Black Rook is the attacker
- White Bishop is defender (Defending king by blocking/interposing)
- White King is the more valuable piece than Bishop.

Therefore Bishop has lost its mobility called PIN. This is called absolute pin as bishop move would be ill-legal move.

While on your left hand side
- Black Rook is the attacker
- White Bishop is defender (Defending queen by blocking/interposing)
- White Queen is the more valuable piece than Bishop.

But here Bishop has some mobility as moving bishop is not ill-legal but not advisable. It is called relative pin.

Pin is possible against square too. Here is an example...

 Here queen on d2 can't move because of checkmate threat on d8.

On next article we will look at getting benefits out of the pin with the help of classical games.

Wednesday, 1 May 2013

Opening Tricks And Traps, Part - 7 - Pirc Defence

Previous : 

PIRC Defence

1. d4 Nf6 2. Nf3 d6 3. Nc3 Bf5 4. Nh4 Bg6 5. Nxg6 hxg6 6. e4 Nbd7 7. Bc4 e5 8.O-O

See the diagram (^) White is having two bishop advantage and nice center but he must be very careful about black's activity on h file

8....c6 9. a4 exd4
(9... Nxe4 10. Nxe4 d5) 

10. Qxd4 Ng4 11. h3 Nde5 ? 12. hxg4 ?? 
See the diagram(^) Now white cannot avoid checkmate, but instead of 12. Be2 and white is having better game 
(12. Be2 Qh4 13. f4 Qg3 14. Bxg4 Nxg4 15. hxg4) 

12... Nf3+ !! is killing one

13. gxf3 Qh4