2014年12月28日日曜日

Basic Tactics For Breaking Yagura Castle (4)

The tactic like ▲N*24 which I wrote in the previous article can be also seen in joseki.
Diag.1 is one of the Yagura Joseki called Katou Style (9-Dan Katou plays this strategy frequently.) It is the sente's variation in Yagura Silver-37 Strategy, characterized by pushing the edge pawn and ▲P-26 before advancing the silver to 46. And, the knight jumps into 25 through 17.


Diag.1

Here, gote plays △N-33 before the attack from ▲S-46 and ▲P-35. In general, the equal exchange between an attacking piece and a defending piece is good for an attacking side. But, in this case, gote has a threat with the knight in the next.
After △N-33, it proceeds with  ▲Nx+ △G32-33x (△Sx and △G43-33x are also available) ▲S-46 (Diag.2). △G32-33x means preparation for the attack from above. It doesn't look like a good shape, though.


Diag.2

In Diag.2, △N*86 is the move that gote had been aiming at since △N-33.
After ▲Px △Px (Diag.3), it looks like there is no piece to drop on 87. But, in the next, it's possible to gain a silver with △Bx46 and drop it on 87. Breaking the point in front of the king is more valuable than bishop-silver exchange. Then, promoting the rook and taking the material back can be expected in the future.


Diag.3

To remove the threat of △Bx46, sente needs to select ▲P-55 or ▲N*79 or ▲Sx.
In reply to ▲P-55, the attack with △N-85 ▲Sx86 △Nx97+ ▲Kx △P*85 (Diag.4) is effective. The silver on 86 cannot move due to the bishop's line. If ▲Lx is played instead of ▲Kx, gote will take the silver with △Bx86 ▲Bx △Rx.
Gote is better at Diag.4 because sente doesn't have a rapid attack to gote's castle yet. As you know, in the endgame, the speed to break the opponent's castle and capture the king is the most important thing.


Diag.4


▲N*79 is the same as ▲P-55. Gote will get better with the attack from △N-85.
Therefore, ▲Sx is a common move in Diag.3. After that, it proceeds with △Bx ▲Bx △Rx ▲P*87 △R-82 ▲P-35 (Diag.5). Many pro players regard Diag.5 as slightly better for gote. Thus, instead of ▲S-46 in Diag.2, ▲N*65 was played in recent pro game.


Diag.5


In this way, even if the position is still in the middle game, the tactic like △N*86 would go well depending on the situation.













2014年12月15日月曜日

Basic Tactics For Breaking Yagura Castle (3)

Continued from the previous article.
http://kingcrimsondiscipline.blogspot.jp/2014/11/basic-tactics-for-breaking-yagura_25.html

▲N*24 is a common tactic of Yagura. Then, as I mentioned earlier, there are some ways dealing with it. Let's look at the actual examples in pro games.
Diag.1 is the game between Daisuke Katagami and Eiji Iijima. It's sente (Katagami) to play.

Diag.1

Here, sente played ▲N*24. What should gote play against it?
If △G32-42 is played, ▲B*65 would be an effective attack. After the rook run to somewhere, with ▲Bx43+ △Gx ▲G*32, it's possible to make the shape for capturing the king. And, △G-31 is also the same thing with ▲B*65. Therefore, gote needs to take the knight. It proceeds with △Px ▲Px (Diag.2).

Diag.2

In Diag.2, gote has three ways to deal with the attack from above. (1) △P*23 (2) △N*31 and (3) △Sx.

(1) △P*23

As I wrote in the previous article, after ▲Px+ △Gx, the castle gets weaker against the attack from the side instead of gaining a knight. In this case, ▲B*41 becomes a fork aiming at ▲Bx23+ and ▲Bx74+. Also, if gote protects the gold on 23 with △P*24, ▲S*32 will be more severe than ▲Bx74+. Thus,  △P*23 doesn't fit into this position as there is a subsequent attack for sente.

(2) △N*31

This move adds the power to 23 in order to remove the threat of ▲S*23. But, as well as when △P*23, ▲B*41 would be a severe move aiming at ▲S*23 and ▲Bx74+. In general, the basis front of the king like ▲P24 should not be left as it is, especially while the opponent has a piece to drop on 23. It's too risky.

(3) △Sx

This is a common move. With ▲Rx △P*23, although gote loses material, he can gain a tempo instead. In the endgame, the speed to capture the opponent's king is more important than gaining material. Basically, when attacked the castle, the defender usually has two plans, continuing to defend thoroughly or countering after gaining a tempo. If it's difficult to stop the attack, the player should select the latter.

Actually, in reply to ▲Px24, Iijima (gote) selected △Sx ▲Rx △P*23. Then, it proceeded with ▲R-27 △N*85 (Diag.3). ▲R-27 means protecting the point on 77 horizontally, and △N*85 added more power to 77.
In Diag.3, ▲S*41 is considered as one of candidate moves. This is also the basic tactic for breaking Yagura. If the gold run to 42, there would be an attack like ▲S*52 △G43-33 ▲B*51.
Katagami played ▲S*65 defensively, though. It would be still an equal game in both cases.


Diag.3

Compared with △P*23 and △N*31, △Sx appears frequently against the attack from ▲N*24.














2014年12月5日金曜日

International Shogi Forum

The 6th International Shogi Forum starts today in Shizuoka City, Japan. This event is organized by Shogi Association once every 3 years, and, this year, 46 players from 38 different countries are supposed to participate in it. I'm just heading there now. There is an evening party today. The tournament will be held for 2 days from tommorow. Besides the tournament, there are other programs, such as exhibition game by pro, instruction game by pro, including me, and chess match between Yoshiharu Habu and GM Peter Heine Nielsen. I'm so excited to join it!

2014年11月25日火曜日

Basic Tactics For Breaking Yagura Castle (2)

Continued from the previous article. 
There is another famous tactic with a knight.


Diag.1

In Diag.1, ▲N*24 is the tactic which is often seen in the endgame of Yagura as well as the previous ▲S*41 and ▲S*52. With △Px ▲Px (Diag.2), it seems like sente lost material, but, the pawn on 24 becomes the basis to attack. While sente has a gold or silver in hand, dropping it on 23 next will be a decisive attack for breaking the castle. Thus, in most cases, gote needs to remove it with △Sx in spite of the silver - knight exchange. After this, it proceeds with ▲Rx △P*23 ▲R-28. 
And, sometimes △N*31 is better than △Sx though the point in front of the king remains as the threat. It depends on the situation which to choose. I think, basically, in case of attempting to attack afterward (to gain a tempo), △Sx should be played, and in case of defending thoroughly without giving pieces, △N*31 should be played.
In addition, in reply to ▲N*24, △G-31 and △G32-42 are also considered unless there is subsequent attack.


Diag.2

If gote has a pawn in hand in Diag.2, with △P*23 ▲Px+ △Gx (Diag.3), gote can absorb the basis on 24. However, this defense doesn't always work well because the shape of the Yagura gets worse instead of gaining a knight, especially against the attack from the side. 


Diag.3

For example, In Diag.4, after ▲N*24 △Px ▲Px, dropping △P*23 is a blunder. There is a mate with ▲Px+ △Gx ▲Rx21+ △Kx ▲Rx23+ △P*22 ▲G*32 (Diag.5). The line from ▲Rx21+ is often overlooked. In general, the rook on 1st rank or 2nd rank in the opponent's camp has a big influence to the castle, therefore the player on the defense side needs to be careful about the various tactics to attack.


Diag.4
Diag.5

Then, △N*31 also get into danger with ▲P-23+ △Gx (in case of △Nx, ▲P*24 is severe) ▲Rx31+ △Kx ▲Rx23+ (Diag.6). Promoted the rook near the king, it's hard to protect even if the defense side gains material. 
Here, △Sx ▲Rx △P*23 ▲R-28 is a common line.

Diag.6

When having a knight in hand, the attacker should play with the tactic from ▲N*24 in mind. On the other hand, the defender has to choose the move suitable for the situation, otherwise the castle would be broken immediately.




2014年11月18日火曜日

Basic Tactics For Breaking Yagura Castle (1)

Yagura has been the popular strategy for a long time, regardless of pro and amateur. Especially, beginners tend to prefer it when the double static rook games. In Yagura, a player can form his own camp calmly without caring about detailed things, compared to Bishop Exchange and Side Pawn Picker which have the risk of losing immediately. But, once the attack begins, it goes for a risky game. Both players need to pay more attention to their king's safety in the endgame.

I introduce the basic tactics for breaking a Yagura Castle.

Diag.1

Looking at Diag.1, experienced players imagine ▲S*41 or ▲S*52 for attack. When ▲S*52, if the gold run to 53, sente can take the opponent's bishop with ▲S*41+ (Diag.2). In general, when trying to break a castle, it's better to attack the gold, not the silver, because the gold is stronger than the silver as a defending piece. It can move six squares, and silver is only five.

Diag.2

As for ▲S*41, it depends on the situation whether it works effectively. In Diag.1, after ▲S*41△G-31, in case of ▲S-52+, the bishop can run to the left, and in case of ▲S-52= (unpromoted), the gold can run to 53. There is no subsequent attack. If sente has a pawn in hand, ▲P*43 would be a severe move to take the bishop, though. ▲S*41 doesn't work well singly. But, by cooperating with other pieces, it works well.

Diag.3

For example, in Diag.3, ▲S*41 becomes a good attack. Continuing with △G-31 ▲S-52= △G-53 ▲S-51= (Diag.4), the attack succeeds. The bishop cannot take the silver due to the rook being on 72. The attack with the rook and the silver is often seen in the endgame of Yagura Strategy.

Diag.4

One more example in real pro games.
It's sente's turn at Diag.5. Although there are no attacking pieces for sente, it's possible to launch an attack with hand pieces, a rook, two silvers, and a knight.

Diag.5

Here, ▲S*41 △G-31 ▲S*52 (Diag.6) is a good tactic for breaking the Yagura. In reply to ▲S*52, if the gold run to 53, sente would keep on attacking with ▲N-43 which aims at the gold on 31. Gote's castle become unsafe immediately.

In this way, if you have a silver in hand in Yagura Strategy, it would be good to consider the way to attack with ▲S*41 and ▲S*52 first.

Diag.6




2014年11月7日金曜日

Bishop Exchange Double Reclining Silver

The 3rd game of the Ryuou Title Match started yesterday. Both players formed a same position in Bishop Exchange Strategy.

http://live.shogi.or.jp/ryuou/kifu/27/ryuou201411060101.html


Diag.1

Identical formation at Diag.1 had been in fashion in pro games until about 3 years ago. But, now, the main variation from Diag.1 almost come to the conclusion that sente is winning. Here, sente opens fire with ▲P-45 △Px ▲P-24 △Px ▲P-15 △Px ▲P-75 △Px ▲P-35 (Diag.2). 4, 2, 1, 7, 3 in order. The way to attack with pushing pawns 5 times in a row was discovered by 9-Dan Maruyama, who is one of the top players.



Diag.2

Originally, in Diag.1, sente was supposed to attack with ▲P-45 △Px ▲P-35, but, there was the counter attack with △P-65 (Diag.3). The sequence Maruyama discovered is aiming to remove such an attack from gote. By pushing the pawn on the 7th file in advance, whenever sente gain a pawn, ▲P-74 would occur, then force gote to play defensively. Although at Diag.3, it is not necessarily bad for sente, it is recently considered that pushing pawns 5 times is better than two times.


Diag.3

From Diag.2, △S-44 ▲Rx24 △P*23 ▲R-29 △G-63 (for protecting the knight's head) (Diag.4) used to be a main line, but, now, most pro players hardly play like this because of the conclusion that sente is winning. There are plenty of complicated variations around here, which many players had been researching for decades. I can't write down all of them. In brief, with ▲P*12 △Lx ▲Px34 △B*38 ▲R-39 △B-27+ ▲B*11 △+B-28 ▲Bx44+ △+Bx39 ▲P*22 △Gx ▲S*33 (Diag.5), sente can finally win. This line is called Tomioka Style (8-Dan Tomioka invented). Therefore, in Diag.2, other lines are required for gote instead of △S-44. For example, △Px35 ▲Nx45 △Sx ▲Sx △B*37, and △P-86 ▲Px △P-76 ▲Sx △Rx86, and △R-81 have been played.


Diag.4

Diag.5

Moriuchi selected the line from △P-86 (Diag.6). It was different from Diag.2 in that sente attacked without pushing the pawn on 2nd file, though. The slight difference may have an influence to the position.

Now, the position is in the endgame.

Diag.6
                           















2014年10月29日水曜日

About a Yagura castle

In Shogi, castling is indispensable to king's safety. It's often said the king should be defended by two golds and one silver. Famous castles are Yagura, Mino castle, Anaguma and so on. A player needs to select a castle suitable for the opponent's strategy.

For example, against swinging rook, building Yagura is not good in general. When putting the king into the castle, the square diagonally front of the king becomes a vulnerable point.
In Diag.1, it's gote's turn. Starting to attack with △N-85 ▲S-86 △P-65, it would be better for gote already. The bishop's path is severe for sente. Thus, in case of castling Yagura, attention should be paid whether the opponent's bishop keeps an eye on one's own king indirectly.


Diag.1

This rule is also applied in Yagura vs Rapid Yagura games.

From first move,
▲P-76  △P-84 ▲S-68 △P-34 ▲P-66 △S-62 ▲P-56 △P-54
▲S-48 △S-42 ▲G49-58 △G-32 ▲G-78 △K-41 ▲K-69 △P-74
▲G58-67  △G-52 ▲S-77 △P-64 ▲B-79 △N-73 ▲B-68 △S62-53
▲K-79 △R-62 ▲K-88 (Diag.2)


Diag.2

Gote's form is a kind of rapid attack strategy which omits moves to build Yagura and tries to attack first. In Diag.2, as in Diag.1, with △N-85 ▲S-86 △P-65, it would be better for gote. The king should not be placed on 88 while the opponent's bishop is keeping an eye on it. The attack from △N-85 is one of the weak points of Yagura. Therefore, according to joseki, instead of the three moves, ▲B-68, ▲K-79, ▲K-88 for castling, sente is supposed to make an attacking formation like ▲P-26, ▲P-25, ▲P-36.

Diag.3

At Diag.3, sente's form is called rapid castling, which is one way of building a Yagura castle. When castling with ▲K-88, ▲G-78 after, sente can build Yagura in fewer moves than usual by omitting ▲B-68. But, in this case, attacked with △P-65 ▲Px △Nx, sente would have a little trouble because the king on the 2nd rank is near the opponent's attack, compared with on the 1st rank. Generally, against rapid strategy, sente shouldn't choice the rapid castling. Looking at △S-33 or △P-44 to go for Yagura, sente should do so.

In this way, depending on the opponent's play, a player need to change one's strategy and castle, not just in Yagura games. I think in the opening it's important to keep the balance.
















2014年10月23日木曜日

The final game of the Ouza Title Match

The 5th-game of The Ouza Title Match between Habu and Toyoshima has been in progress today. So far the score is in a tie, 2 to 2. The winner of this game is able to win the Ouza Title.

http://live.shogi.or.jp/ouza/kifu/62/ouza201410230101.html

Side Pawn Picker, Bishop-33 Strategy has been played, which is one of the most popular strategies among pro players, especially among young pro players. This is because it wins over 50% these days in spite of first-mover advantage. Generally, in Shogi, as in Chessfirst-mover advantage exists certainly. Sente has been winning about 52% in all pro games, and this tendency is particularly strong in top title games. Thus, gote relatively tends to choose the strategy which has a higher winning rate.


Diag.1

Bumping the rook with △R-24 after advancing the silver to 23 is the tactical move discovered recently. In this position, sente cannot take the rook because there is no place to drop it in gote's camp after the exchange. On the other hand, gote can drop it on 27 and 28 to make a promoted rook. However, depending on the situation, it's possible to take the rook on 24 e.g. In case of ▲K-58, ▲S-48, ▲G-38, there is also no square to drop it in sente's camp. In fact, Habu has played this line in his games.

From Diag.1, it proceeded with ▲P*25 △R-74 ▲S-37 △K-62 (Diag.2)


Diag.2

△K-62 is also the move which is often seen recently and has never played before, as well as △R-24. The aim is to go away from the opponent's rook and to build a Mino castle. If opened fire from 2nd or 3rd file in the future, gote would be able to play more offensive than the king being on 52. These two moves are in fashion in Side Pawn Picker.


Diag.3

The current position is at Diag.3. It's still in the middle game. Perhaps piece-building will continue for a while. I suppose sente will form the castle better, such as Yagura or Silver Crown, and attempt to oppress the rook on 74 little by little.