Life In 19x19

Say the enemy has a two-point extension on the third line, and you have stones on both sides of it, as in the diagram. How can white attack the black group?

Click Here To Show Diagram Code

[go]$$W
$$--------------------
$$. . . . . . . . . .
$$. . . . . . . . . .
$$. O . X . . X . O .
$$. . . . . . . . . .
$$. . . . . . . . . .[/go]

Mark356 wrote:Say the enemy has a two-point extension on the third line, and you have stones on both sides of it, as in the diagram. How can white attack the black group?

$$W
$$--------------------
$$. . . . . . . . . .
$$. . . . . c . . . .
$$. O . X . . X . O .
$$. . . . . b . . . .
$$. . a . . . . . . .
$$. . . . . . . . . .

Click Here To Show Diagram Code

[go]$$W
$$--------------------
$$. . . . . . . . . .
$$. . . . . c . . . .
$$. O . X . . X . O .
$$. . . . . b . . . .
$$. . a . . . . . . .
$$. . . . . . . . . .[/go]

As usual when attacking a group, there are three general-purpose aims to consider.

a) pressure it while expanding a moyo
b) seal it in and build central influence
c) steal its eyes and chase it away screaming (preferably your stones will be wearing blue face paint and waving broadswords and axes for this one)

The global situation is going to be the deciding factor in which of these approaches you choose, and which direction you place the stone from (since it's symmetrical, all three of my attacks above are from the left - b and c are likely to connect to the left rather than the right, so I think of those as also being "from the left" even though they start closer to the right side.)

B was a lot less common when I was first learning, but thanks to the mini-Chinese opening I think most players are familiar with it by the time they reach 1 dan now. It usually goes something like this:

Click Here To Show Diagram Code

[go]$$W
$$--------------------
$$. . . . . . . . . .
$$. . . . . . . . . .
$$. O . X 6 2 X . O .
$$. . 7 3 4 1 . . . .
$$. . . . 5 8 0 . . .
$$. . . . 9 . . . . .[/go]

Click Here To Show Diagram Code

[go]$$W
$$--------------------
$$. . . . . . . . . .
$$. . . . a a . . . .
$$. O . X . . X . O .
$$. . . . c c . . . .
$$. . b . . . . b . .
$$. . . . . . . . . .[/go]

To be a bit redundant, "a" is the standard attack to deprive Black of eyes, and "b" is an attack on a larger scale. "c" is possible, but, as it solidifies the Black group (weakening one of the White stones), usually happens when White has only one nearby stone, instead of two.

Click Here To Show Diagram Code

[go]$$W
$$--------------------
$$. . . . . . . . . .
$$. . . . . . . . . .
$$. O . X . . X . O .
$$. . . . . . . . . .
$$. . . d . . d . . .
$$. . . . . . . . . .[/go]

All of the above are standard points. A small addition: given the right circumstances, a cap at d can be good as well. Of course, it leaves a gap, but it also makes it a lot harder for black to make eyes. Use at your own precaution though!

Yeah, usually I play a keima, a in ethanb's post, because it's safe, and if nothing else, I'll build on my own strength. I was hoping there was some sort of standard sequence for expanding on c, though, because even though I've seen kills that way, I can never make it work myself.

@gaius: d looks a little odd to me. It leaves 2 gaps: the one-point jump from the other stone, and the elephant's eye. Sometimes I'll use a cap like that on a single invading stone, the capping stone being a hazama tobi or a crippled horse from any friendly forces, the goal being that the invader will try to escape, and I'll make territory while chasing him all across the board. But with 2 stones, how would it work?

Sorry to bump an old topic - but I also am wondering a lot about the approach "C" to the 2-space extension. I have seen it a few times in my games. Here is an example in a recent game (BTW, is my play on the side the ideal point in this part of the opening?)

Are there any standard sequences after "C"?

Standard sequences are only guidelines, and could be absolutely terrible given the position of the rest of the board. With that in mind, you should notice you tend to have two options: 'a' and 'b'.

Click Here To Show Diagram Code

[go]$$ I know I just said the whole\nboard is important. I'm low\non time. Shut up .
$$--------------------
$$. . . . . . . . . .
$$. . . a O . . . . .
$$. O . X b . X . O .
$$. . . . . . . . . .
$$. . . . . . . . . .
$$. . . . . . . . . .[/go]

If you play 'a', while will try and connect to the other stone.

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[go]$$ One possiblility
$$--------------------
$$. . . . . . . . . .
$$. . . 1 O 6 4 . . .
$$. O . X 5 2 X . O .
$$. . . . . 3 . . . .
$$. . . . . . . . . .
$$. . . . . . . . . .[/go]