Hovercraft
Charles See also Joseki-related life-and-death example 2.
This is another shape often resulting from a 3-3 invasion.
Let's try a few attacks for White.
Hane
Black has to let go two stones, or ...
He will die after 2.
Black lives, but White can make an endgame gain at a.
Bildstein: What's wrong with making the L+2 group, and saving all 6 stones? Benjamin: Yeah, maybe the solid connection is best. You should just keep in mind that this time, the other white descent (on top) is sente, as this will threaten a ko - how to do so is homework ;-)
(to be completed - feel free to add)
If white has the marked stone, for example because black threatened to connect an outside group here, the corner can now be killed.
--Bass