B2 Bomber Josekis

    Keywords: Humour

Table of contents Table of diagrams
Approaching a !B2 Bomber
!B2 bomber low approach
!B2 bomber high approach
!B2 bomber distant low approach
!B2 bomber distant high approach
!B2 bomber very distant low approach
!B2 bomber very distant high approach
!B2 bomber very high approach
!B2 bomber distant very high approach
!B2 bomber 3-3 invasion
!B2 bomber kamikaze
!B2 bomber [mochikomi]
!B2 bomber pseudo-approach
!B2 bomber side attachment
!B2 bomber tenuki
Moves 5-14 of a game, with hoshi-based B2 in play
Moves 16-17: The bomber takes off...
Moves 18-19: The bomber starts attacking
Moves 20-21
10 seconds after Move 21: Ouch.
Result of the bombing: W+Res.
Taisha Bomber
A common reduction technique
The 21st Century Approach
The mistake is to allow the [trumpet connection].
Avoiding the bomber
Attach-Block
Fighting B2Bs
Fighting B2Bs--Followup
White Resigns
Black Resigns
Black Resigns


Approaching a B2 Bomber


WARNING: DO NOT TRY THIS IN YOUR GAMES!

#11 #09 #01 #03 #05 #02 #04 #06 #07 #08 #13 #10 #14 #12
[Diagram]
Approaching a B2 Bomber  





[01]

[Diagram]
B2 bomber low approach  

The sequence after W5 is similar to 4-4 point low approach, one-space low pincer, one-point jump.

[02]

[Diagram]
B2 bomber high approach  

(W11 at a, B12 at b.) Please note that this is generally considered a special strategy-- white stops the bomber from taking off at the cost of ending up with bad shape AND giving black lots of solid territory. Then again, black's B2 has already enclosed too much territory to begin with!

[03]

[Diagram]
B2 bomber distant low approach  

(W11 at a, B12 at b, W13 at c, B14 at d, W15 at e.)

[04]

[Diagram]
B2 bomber distant high approach  

Black gets a lot of territory on the left but is somewhat overconcentrated.

[05]

[Diagram]
B2 bomber very distant low approach  

Both sides follow the wall height + 1 rule.



[06]

[Diagram]
B2 bomber very distant high approach  

Similar to [05].

[07]

[Diagram]
B2 bomber very high approach  

This is playable with a side stone already present. White plans to build a moyo along the top.

[08]

[Diagram]
B2 bomber distant very high approach  

Same idea as [07], except that the side stone is one line over.

[09]

[Diagram]
B2 bomber 3-3 invasion  

You might want to first refer to Three Crows, because the invasion should not succeed even with outside support. It might be useful as a pseudo-ko threat against a DDK in the situation above, though.

[10]

[Diagram]
B2 bomber kamikaze  

The marked white stones are not necessary, but they might be useful. This should only be attempted as a last-resort, as you're stopping a B2 by crashing another one into it.

[11]

[Diagram]
B2 bomber mochikomi  

Well, I assume this is a misclick. Even with support as shown, white shouldn't play like this. Black should obviously play elsewhere.

[12]

[Diagram]
B2 bomber pseudo-approach  

This is a light way to handle Black's B2 bomber. It is far enough that black's B2 influence has little effect on it, yet close enough that it can stop the B2 like a ladder breaker.

[13]

[Diagram]
B2 bomber side attachment  

This is a possible alternative to [12] if white wants to stop the B2 without getting overconcentrated.

[14]

[Diagram]
B2 bomber tenuki  

If white already has three bombers as shown, playing elsewhere is probably the best option.




A Really Bad Example

Please note that the sequences given above should definitely be played when a B2 bomber is already present, because stopping the bomber is more urgent than any another move. The following is an example of what might happen if the bomber is not stopped in time.

[Diagram]
Moves 5-14 of a game, with hoshi-based B2 in play  

W4 through W10 may seem strange, as they are definitely too slow. But they do serve a purpose-- sente is given up temporarily to make a B2 bomber.

Theoretically, black is supposed to make a three-space extension from the wall to a at move 17. However, this is a mistake, because white can now bring the B2 bomber into action...

[Diagram]
Moves 16-17: The bomber takes off...  
[Diagram]
Moves 18-19: The bomber starts attacking  
[Diagram]
Moves 20-21  
[Diagram]
10 seconds after Move 21: Ouch.  
[Diagram]
Result of the bombing: W+Res.  

Needless to say, black has no option but to resign.



Application: Taisha B2 Bomber

[Diagram]
Taisha Bomber  

Anonymous: 7 is a famous trick play in this line, 8 is a common mistake, White wastes no time in playing at 9. This is a great way to avoid the taisha.




Another Application: Using a probe to get a B2

George Caplan: There is an even more common opportunity to use the decisive properties of the B2Bomber in actual games. Forgive my first attempt at diagramming, but here goes.

[Diagram]
A common reduction technique  

Takemiya Masaki presents this technique in Enclosure Josekis. He specifically cautions against 9 at "a" because the postion will become "overconcentrated" and because of the peeps available to White.

Obviously, this old book is outdated - the time of "shape" and "light" is over - today we play for power and results.

[Diagram]
The 21st Century Approach  

In fact, B1 here is a trick play, trying to induce the peeps that Takemiya warns against. The result? White actually forces Black to make a powerful B2Bomber formation, at the cost of only one stone!

White's shape here is horrible - the four stones that capture black's first move are ok, but the 3-3 pt stone seems redundant and the rest of White's plays are too close to Black's thickness or hopelessly scattered.

Black, on the other hand, again, with one brilliant sacrifice - forms a perfect B2Bomber - all in what was originally White's position!

Now, we always should be careful evaluating results without seeing the rest of the board, but it is hard to deny the power of Black's position here. Absent White having a B2Bomber of his own, in the near vicinity, this has to be a success for Black.

It is indeed fortunate for Takemiya's well deserved reputation that "Enclosure Josekis" is out of print and hard to find.

[Diagram]
The mistake is to allow the trumpet connection.  

unkx80: The mistake here is actually to allow trumpet connection at B1. Since White a or b will only get captured, there is no way to prevent Black from playing both a and b to form the all powerful B2 bomber.

[Diagram]
Avoiding the bomber  

Alex: Right. White has no choice but to play this way. Black gets to capture one stone with B9, but after W10, there is no way for him to make a bomber.

Fighting B2B Joseki

erislover: There is a little-known B2B joseki based off the 4-4 point. Both sides get a bomber and the outcome is wildly unpredictable.

[Diagram]
Attach-Block  

Black starts out with the attach-block sequence. Traditional views of this sequence consider it to be a primarily defensive measure. But recent innovations in thickness and influence have yielded the following joseki:

[Diagram]
Fighting B2Bs  

W1 begs black to make the trumpet connection, anticipating black's desire for the B2B. After the atari kikashi at W3, white whips out a trumpet shape of her own! This sets the joseki on a forced course up to B10 where both sides get a B2B. The results from this joseki are unclear, but usually considered just slightly better for white due to black ending in gote. This may soon be a rejected bit of conventional wisdom because normal understanding of sente/gote relationships are very unclear around B2Bs.

[Diagram]
Fighting B2Bs--Followup  

A typical followup to the Fighting B2B joseki is W1, threatening to unleash another bomber. Black wisely plays B2 to prevent it from forming.



Another Game Position

[Diagram]
White Resigns  

Blake: White has no chance to protect her alabaster city in this position; it's best for her to resign.

[Diagram]
Black Resigns  

Celebrir:But White has three hidden B2 Bombers ! (circled Stones) Besides, if it's Whites turn, white gets four more B2 bombers. That makes a total of seven against three B2 Bombers. Now B has to resign !

Anonymous I just want to point out that there are a couple other B2 Bombers White can make

[Diagram]
Black Resigns  

B2 Bomber Josekis last edited by 24.205.252.66 on January 8, 2019 - 01:01
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