Sunday Problem #48

Like Problem #12, this is from the Collection of Tsumego Masterpieces by Sekiyamas Riichi, Toshio, and Toshimichi. This time, Black has to try to make life in a very cramped corner setting.

Black to play.


Oscar on Games of Fujisawa Shūkō 9p

Streamed on Twitch on May 1, 2021.


KataGo’s ‘Perfect Selfplay’

This commentary on KataGo’s self-played game is originally from my Kifu newsletter last September. I am now publishing this as free extra content to our website’s readers.

The KataGo that plays black and white in this game is the newest 40-block version from last September, with playout counts at best rising to about 1,000,000.

See full post to read kifu annotations!


Sunday Problem #47

It looks like this white corner group is difficult to capture unconditionally, but there is a surprisingly clean sequence hiding in plain sight.

Black to play.

Solution
Failure (1)
Simply turning with black 1 is not enough. White claims the key point of 2, and then for example black 3 and 5 get refuted by White’s 4 and 6. White …

Read the full post here!


Sunday Problem #46

Like last week’s problem, this is also a classic tesuji problem.

Black to play.

Solution
Solution (1)
Black does not have much choice but to start with 1, but in response to this White launches the attachment of 2. After this, the rest of the problem is about how Black can avoid having to fight a kō.
Black’s 3, 5, and 7 are the key tesuji combination. Following, even though White can capture two stones with 8–
Solution (2)
–Black recaptures with 9, and wins the capturing race directly.

The Universal Rule of Shape

No matter your intention, shape should always come first!


Sunday Problem #45

This is a classic tesuji problem. I unfortunately don’t know the origin; my source material is a tsumego printout from a dōjō I used to go to when I was insei.

Black to play.

Solution
Solution
Black’s first-line peep of 1 is correct. To keep attacking, White has to connect with 2, but then 3 ensures Black’s group has four liberties and so she wins the capturing race.

Jeff on Managing Time Pressure

Streamed on Twitch on April 10, 2021.


Sunday Problem #44

This problem is from Nihon Ki-In’s 150, or 150 Graded Life-and-Death Problems for 7-Dan Players.

Although this shape is hardly anything that could occur in a real game, personally I like this problem because of its straightforward and yet extremely non-obvious solution.

Black to play.

Solution
Solution (1)
For Black’s first moves, there is nothing else to …

Read the full post here!


Sunday Problem #43

This problem is from Guanzi Pu. Black needs to think of an unconventional response to White’s second-line peep on the right side.

Black to play.

Solution
Solution
Black’s unlikely jump of 1 is correct, and the only choice for the first move. If White cuts with 5 in response, Black can form life in the corner and capture White that way.
However, our reading should not end after black 1, as White still has a resistance available. White 2–6 manage to create a two-step kō for life that Black cannot prevent.
Instead of 3, Black can also pick the move order of 5-6-3-4.