Hovercraft

Hovercraft  

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

Let's try a few attacks for White.

Hane

First hane  

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

Problem  

He will die after 2.

Life  

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

Alternative Way  

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

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.

"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!

My hovercraft is full of eels.  

Bent four in the corner.

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 .