Episode #10 Daidaigeima (大大ゲイマ)
The formation on the board is a popular [shimari].
The knight's move that black makes with [A] is called a [keima].
Black could also choose to play a big knight's move. This is called [ogeima] in Japanese.
Going one step further, the marked white move here is called the Daidaigeima (大大ゲイマ)
An extra large knight's move.
In this episode we will focus on a joseki which starts with a [daidaigeima].
But first we will show you another popular joseki with an [ogeima].
When black pincers here, white's [ogeima] is a popular response.
This joseki is good when black has a solid position in the upper left corner.
Like this.
Here the marked stone is a good joseki choice.
This joseki has many variations, but this one is the most common.
This finishes the most well-known variation of this joseki.
Notice the move that started the joseki: the marked white [ogeima].
There is not much life left in that stone.
Instead of playing the [tiger's mouth] in the previous variation, white can also extend into the corner if the ladder is favourable.
[A] is the ladder breaker which makes this extension possible.
First we will show you the ladder joseki and why it doesn't work for black.
This is the ladder, but now this doesn't work for black.
But instead of trying to ladder white immediately, black can also try ladder breakers of his own.
He can start fighting in the lower left corner with [A]. See the game between Kobayashi Koichi and Yamashita Keigo.
Instead of immediately cutting, black also has a tricky move up his sleeve.
Black can try this sneaky attack. It threatens to cut at [A].
If white plays tenuki..
..he is tricked!
The same variation as before is played.
I'll jump forward.
Oh sorry! I meant jump forward in the game record.
Instead of laddering with [A], black has this keima tesuji!
The two white cutting stones are captured.
This is the best white can do.
The marked stone makes sure black can capture white in a ladder.
This is the ladder. We hope white doesn't give up on go.
Instead of playing the [ogeima] with [A], white can also choose to play this [daidaigeima].
The idea is that if black plays the same sequence as in the [ogeima] variation..
..white is happy.
The marked white stone is in a much better position now than in the previous [ogeima] variation where it was placed at [A].
So black will probably try something else instead.
This is a good move. The focus is on the two cutting points both players have at [A] and [B].
White can choose to fix his cutting point immediately.
Normally this is bad style, but because black still has to take care of his weakness at [A] he can not respond at [B].
This is playable for both sides. See the attached progame between Lee Changho and Kang Dongyun for an example of this variation.
Instead of protecting his weakness at [A], white can also play at the [3-3 point] here. This aims at cutting at [A].
A difficult variation follows when white cuts.
Both black and white's groups have 3 liberties. So black will win this race.
White however gains outward influence.
This is a joseki. Note that [A] and [B] are sente for white, so he is quite thick.
See the professional game in the bonus tab between Kang Yotaek and Kang Changbae.
To conclude, try this Daidaigeima (大大ゲイマ) sometime.
It will probably surprise your opponent and will result in new interesting variations.
Thanks for watching and see you next time.