Small avalanche - trick play
is natural to prevent the ladder, but after , it seems that White has a problem. The tesuji at saves the day.
With the moves up to , Black can cut off , but White takes the corner and manages to escape with as well.
With , White has fallen for the trick play. With the moves up to , Black seals white into the corner while cutting off . White can push through at a, but b is atari, forcing White to capture, after which Black can finish his wall with a move at c.
is even worse. After , the white groups are disconnected and heavy.
As white descended she has an extra liberty and can push through and capture the stone on the 2nd line in sente, which is a big improvement over the previous diagram. I (Uberdude) think this is playable for white as she gets sente and there is still some aji on the outside: activating the marked cutting stone and the peep at a are things to look forward to.