Chess program, Lesson 4

Tacticooloo 

The Gueridon mating pattern

1. e4 e5
2. Nf3 d6 – the philidor defence
3. Bc4 Be7 
4. d4 exd4 



– you should notice here (according to what we’ve studied so far) that black’s surrender of the centre was premature and unneeded. Better was to play 4… Nc6 reinforcing the centre.

5. Nxd4 Nd7??? – From this point on black will face nothing short than utter destruction! for our purposes it’s interesting to notice that black played three developing mistakes. The first one was 2…d6. Although this is a known defence it goes against the developing rules we learned! The second mistake was 4…exd4, the premature surrender of the centre which gave white the extra space, extra activity and finally the control over the d-file which is the very means of white’s successful onslaught! And the third and last blunder was 5…Nd7 blocking the development of the LSB and shutting the queen away from the game.



6. Bxf7+!! Kxf7 – it’s very difficult to see white’s next move unless you’re familiar with it. I’ll give you a minute to see if you can spot it.

7. Ne6!!!



– At first this seems like nothing short than a blunder! And indeed what happens if black plays KxN?

7… Kxe6
8. Qd5+ Kf6
9. Qf5# 1-0

In reality black can’t do anything to escape from his lost position. And interesting try for black is to put the queen out of harms way. So instead let’s consider the move:

(7... Qe8
8. Nxc7 Qd8
9. Qd5+ Kf8
10.Ne6+ Ke8
11. Nxg7+ Kf8
12. Ne6+ Ke8
13. Qh5#) – no escape from the checkmate!

This next example is taken from a Blackburne game.



1. b4+ Bxb4
2. Bb6+ axb6
3. Qxa8# 1-0

Here we can see that white (after going on a successful king hunt) used the b-pawn to take away Black’s flight square.

We will now examine the Greco Sacrifice Pattern

1. e4 e6
2. d4 Nf6
3. Bd3 Nc6
4. Nf3 Be7
5. h4 O-O
6. e5 Nd5
7. Bxh7+ Kxh7
8. Ng5+




The Greco pattern is easy to understand and therefore easy to prevent. Still, you’ll find that it’s not only effective in its own, the position it creates where white either has an open h-file to harass black or the beginning of a king hunt is difficult for black to defend.

In reality after the move Nf3-g5+ black is already lost no matter what he does!
It’s important to notice here the preparation that white took in order to unleash the Greco.
First of all, white kept the tension in the centre till it was in his advantage to release it. A computer will never see a Greco-type-pattern because it would have played the move e4-e5 earlier. By the way there are certainly positional justifications for playing e4-e5 earlier as well as un-positional reasons for not playing h2-h4 altogether!

On the other hand the opportunities it gives white to fight for the win and maybe even more important, all the opportunities it gives black to go wrong can not be underestimated.
In the end the moves we make have POU (philosophy of use) hat appeals to us, some players may fancy the possibilities of h2-h4 while other will consider it an inaccuracy. Both POUs are right!

Learning the Greco will open your life to a whole new world of possibilities. There are also ideas like playing Ng5 or Bg5 before Bxh7+ and then when black plays h6 to attack whatever piece white placed on g5 white answers with? h2-h4! Offering the piece for the gaining of an open h-file. But we’ll get to that later on.

So at this junction I would like us to examine some of the possibilities black has and how white reacts to each of them. You’ll see that they combine several of the other tactical ideas we mentioned so far. Like discovered attacks, double checks, the occupation of important attacking lines etc.

Before we examine this position I would like you to look at it again now grasping all the weak diagonals, key squares and possible moves.



Moves that we will examine are these:
A) Kg8
B) Kg6
C) Kh6

A) 8… Kg8
9.Qh5 Bxg5 – otherwise Qh7#
10. hxg5! – opening the h-file where the Queen and Rook work together
10… f5 – only move
11. g6! – taking out the King’s escape (flight) square. With either Qh7# or Qh8# on the next turn. Game over!

B) 8... Kg6
9. Qd3+ f5
10. exf6+ Kxf6
11. Qf3+ Kg6
12. h5+ Kh6
13. Qd3!! – an important move! taking control over the d3-h7 diagonal which empowers white’s threat of Nxe6+(discovered check and attack on the Queen) where black will find that he even has less squares to run to and that his Queen is gone! So although Qd3 is somewhat a quiet move, not checking or sacrificing anything right away it’s a powerful one. Methodically speaking, this is a part of the technique you employ when building a mating net.

13…Rf5
14. Nxe6+ Kh7
15. Qxf5+ Kg8
16. Nxd8 Nf6
17. Nxc6 dxc6
18. Qg6 Bf8
19. h6! Bd7
20. hxg7 Bxg7
21. Bh6 Ne8 - (21... Re8+ 22. Kf1 – and the Knight can’t go to e8 to defend g7)
22. Rh4!! – with the idea of Rh4-f4-f7 attacking g7!
22… a5 23. Rf4 a4
24. Rf7 Rd8
25. Rxg7+ Nxg7
26. Qxg7#

C) 8... Kh6
9. Nxe6+ Ne3
10. Qd3!! – either way black is doomed. His desperate attacking move was designed to confuse white. Many moves win here of course including the straightforward 10.Bxe3+ but there black has that one extra non-forced-move which gives him the time to play g6. for instance after the continuation Kh7 Qd3+ g6. therefore white play Qd3 right away leaving his Knight on e6 to be captured since Bxe3+ will place the black king in an immediate mating net with but one square to go to. For instance after:

C1) 10…dxe6 11.Bxe3+ Kh5 12. Qh7+ Kg4 13.Qe4+ Kh5 14.g4#

C2) 10… f5
11. exf6 Qe8 – there are many failed attempts here for black that theoretically speaking will lose slower but for our purposes we can establish that if black loses his queen too it is surely over and there is no point in analyzing it further anyway! So let’s see what happens if black tries to defend his queen.

12. Bxe3+ Kh5
13. Qf5+ g5
14. Qxg5#

The Queen Sacrifice mate



1.Qxf7+ Rxf7
2. Rd8# 

The Boden’s mate

This mate usually occurs when your opponent castled queen side.
Some call it the Bishop’s mate, or the crisscross mate or the Alekhine mate.



1. Qxc6+ bxc6
2. Ba6#


Blackburne’s mate

This mate can be found in various formations and numerous opening set ups. It’s important to focus on the important factors that create the mating net. These are the Queen, the Knight and the Two Bishops. In fact if you have something else to replace the Queen’s sacrifice you can create the mating net with the Knight and Bishops alone.
This tactic will only work on a fianchettoed pawn structure without the corresponding Bishop, in this case that will be the lack of black’s DSB.



1. Qh4 h5
2. Qxh5 gxh5
3. Bh7#


Queen and Pawn mate




1.f6 g6
2. Qh6 Qe5
3. Qg7#


The h-file mate (Rook & Bishop)




1. Rxh7 Kxh7
2. Rh1+ Kg8
3. Rh8#


The Pillsbury mate




1. Rxg7+ Kh8
2. Rg8+ Kxg8
3. Rg1#

The next position that we’ll examine is a very interesting one to say the least!
I’ve learned a lot from it personally.

W


First of all let us examine the position.
Material count is interesting, white is a Knight up yet two pawns down.
Both sides have moved their Kings hence neither side can castle.
White is more active, having three minor pieces in the centre (controlling black’s camp)
White has a lead in development and more space.
The White queen is under attack! Therefore unless white moves the Queen or finds a forcing combination black will surely play bxa5 with a won game despite the other deficiencies.
Black has threats of his own for winning the lost piece. For instance a maneuver like …Ng6 / Bxd6.
White can’t take the time to protect his King with moves like h3 since then …bxa5 wins for black.
If white tries to be “smart” and offer the piece back with the move g3 black can out smart him and play Qxf3! Where the Queen still hangs as well as the h1-Rook and black quite simply wins.

If you’ll input this position to a computer engine it will surely calculate all variations and find the best positional spot for the White Queen. That being on c3.

Therefore, the best positional move in this position is 1.Qc3! protecting the Bishop on c4, attacking the g7 pawn (and indirectly attacking the Rook) with ideas such as Nd4 or Rd1 with a won position that needs to be won.
Certainly this is not a difficult task for even the weakest of players. Surely even a novice could win this position even if he would miss the best moves move after move second moves and even third best moves will win just as well!

Still black has some easy-to-see counter measures with ideas such as …Nd5 blockading or …Ng6 with …Bxd5 or …Nf5 attacking the Knight on d6 or …Bb7!? Creating pressure along the diagonal where if white isn’t careful and moves his f3 Knight he will get mated! Or ideas with …Rg8/g5 with chaotic counter play.

With accurate play and time on your clock indeed 1.Qc3 would be best none the less. But if you want to create more options for your opponent to go wrong, if you want to put him in a position where he has less options to choose from and play more forcing moves you might result this positional tension with tactical play and not positional / strategic one.

Therefore white has a really nice trick here, I will give you a minute to try and spot it.



1. Ng5!!! – Amazing move! This initiates the Knight(s) checking tango 
1… bxa5 – we’ll consider other moves later
2. Ngf7+ Kc7
3. Ne8+ Kb6 
(if 3... Kb7 4. Nd8+ Kb6 5. Bd4+ Qc5 6. Rb1#)

4. Bd4+ Kb7
5. Rb1+ Qb6
6. Nd8+ Kb8
7. Be5+ d6 8. Bxd6# 
Analysis:
In reality the best move for black after 1.Ng5 is 1…Ng6 creating a flight square so to meet 2.Ngf7+ with 2…Ke7.
What’s interesting here (and this is something a computer will never understand) is that after 2…Ke7 White can now go back to playing 3.Qc3!! with roughly the same ideas he had before but far less ideas and counter play for black!!
The King is stuck in the centre blocking the f7 Bishop from both developing and capturing on d6. the Knight has already committed itself to g6 so in truth we reached the same set up the computer was so positionally fond of but with better play for white and worse play for black.

In addition the Back King’s position is slightly worse since White now has the threat of Qc3-g3-g5#

Here the only move that black can play and try for anything is 3…Bb7 but white easily stops this threat with the move 4.Rg1!! then Black can hit further more with 4…Rc8!? Here white can’t play Qg3 because of QxB+
But white can go for some forcing lines where there is a lot of smoke to be cleared but once cleared white will be on top.

5. Qd4!!

(5. Qd2 – will achieve the same forcing trading line but will offer black less chances to go wrong! The trading line is: 5…Qxc4+
6. Nxc4 Rxc4
7. Nxh8 Nxe5
8. Qg5+ Ke8
9.Qxe5 with the idea of Qb8+ game over)

5... Qc5

(One way for black to go wrong will be 5... Nxe5 6. Qh4+ g5 7. Qxg5#)

6. Qd2 – with the same variation as before. 1-0

Accurate knowledge of tactics allows you to play accurate defence!

Positions: