Black to play and win (9x9 / 5.5 komi / Japanese rules)

I missed a possible way to win in the actual game. Most paths lead to W+0.5 or worse.

Analysis board for sharing variations


I would have never guessed, it looks like a B done deal to me.
I need more 9x9 in my life.


I don’t see
Optimal would be to get sente on the life of the bottom group while saving B4 so then you can play C9 first.
How i dunno. Maybe start with B2?

1 Like
Some idea

Not sure if this works. There are so many branches. First move B2. Then the top left is a seki if white tenukis; in the bottom right corner D1 is pretty severe.


Following the 1-2-3 principle, Black can skip B2 and play the first move at D1.

White naturally wants to resist at 2, but once Black blocks at 3, White doesn’t have enough liberties to keep resisting at 4. White would lose all four stones.

White can try 4 at F3, trying to fix the problem in sente. But F3 isn’t sente at all. In fact, Black’s moves at 5 and 7 are sente, so White gained nothing.

White’s last and best continuation is to just draw back with 4. But it’s not enough. Once Black draws back in kind at 5, Black successfully dented White’s position, and White can’t achieve better than B+1.5 if Black responds accurately. I shared a sample ending to the analysis board.

Since resisting at C2 fails, Black D1 is good, and White can think about applying the 1-2-3 principle, omitting the bad move, and drawing back with 2 to begin with. This outcome is the best yet for White, but KataGo still gives winning paths for Black with both A and B, though the position is still really volatile and hard to read.

The game: mark5000 v. GM.lovecall (Oct. 12-17, 2021)