GSATE problem 99

Problem 99  

What is Black's tesuji in this position?

Book Solution (White 3 points - Black Sente)  

the solution says 1 is hard to see and that white must pull back to 2 to make 2 eyes, and that black 3 is then sente.

Hmm?  

KarlKnechtel: White has to 'pull back'? Why? I don't see any way of killing this shape.

This way  

ChessWhiz: Although I don't see a way to kill, this result is even better than the solution -- only 2 points for white, and black has sente. If instead at 5, at 4, putting half the group in atari and killing the rest.

My solution -- Show me where I went wrong (White 2 points -Black Sente)  

Seems 1 threatens to kill white with a shortage of liberties, White is reduced yet another point in sente.

I don't think so.  

unkx80: Black loses points instead.

Joeseki: Thanks! I initial thought Black could play 3 to the left of , but at 6 would be fine for white as well.