Hovercraft

  Difficulty: Intermediate   Keywords: EndGame, Life & Death, Go term

See also Joseki-related life-and-death example 2.

[Diagram]

Hovercraft

This is another shape often resulting from a 3-3 invasion.

Let's try a few attacks for White.

Hane

[Diagram]

First hane

Black has to let go two stones, or ...

[Diagram]

Problem

He will die after 2.

[Diagram]

Life

Black lives, but White can make an endgame gain at a.

[Diagram]

Alternative Way

When the tail consists of three or more stones, and/or the outside cutting point is important (in this case a), B4 connect is better. This results in seki at worst. White may play W5 at B6 to seal the top edge, forcing B6 at W5.


[Diagram]

L+2 Group

Making the L+2 group saves all 6 stones but this time, the other white descent (on top) is sente, as this will threaten a ko.


[Diagram]

"Hovercraft" with descent

If white has the marked stone, for example because black threatened to connect an outside group here, the corner can now be killed.

Sandra: If it’s black turn, can it be saved?

MrTenuki: Yes-- one option would be connecting at a. The point here is simply that the marked White stone changes the status of the Black group from alive to unsettled.

Sandra: Thank you!

[Diagram]

My hovercraft is full of eels.

Bent four in the corner.

[Diagram]

In a recent game of mine.

What about this? How should you respond to move 4 here to kill?

Just connect with 5. If white 6, just atari 7 kill. If white play something else instead of 6, it's already dead or dead in bent 4 .


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