Answer to Problem 14

Dia. 1. Correct
Dia. 1. The descent
If Black descends to the first line with 1, his stones are unconditionally alive.

Instead of 1, if Black plays at 'a', White answers with 1–Black 'b'–White 'c', resulting in a ko.

After Black 1 —

Dia. 2
Dia. 2. Black lives
White tries to kill Black with a placement at 2. Black responds by making an eye in the corner with 3. If White 4, Black blocks with 5 and captures the stone at 2. His stones now have two eyes.

Dia. 3
Dia. 3. A four-space eye
White might push in with 2, but Black simply blocks with 3 and he is left with a living four-space eye.

Dia. 4.
Dia. 4. An inexplicable move
So why are we presenting such a simple problem?

The game in which this position arose was played between Iyama Yuta Kisei (white) and Kato Atsushi 9-dan in the quarter finals of the 31st Ryusei tournament on September 26, 2022. Both players were under time pressure. That is, they had only 30 seconds to make each of their moves.

This was the position after 181 moves. It seems as if Iyama is ahead. Iyama plays an endgame move with the hane of White 1. Black blocks with 2 and Iyama, instead of simply connecting at 'a', inexplicably cuts with Black 3, allowing Black to start a ko at 'a'.

Next —

Dia. 5.
Dia. 5. Quickly resolving the ko
Black takes the ko with 4 and White make a ko threat with 5. Black resolves the ko with 6 and 8, and White captures five stones with 9.

If Black now plays at 'a' he wins. Instead —

Figure 1 (191–225)
Figure 1 (191–225). Continuing with the endgame
Seemingly, Black mistakenly assumed that his marked stones were dead as they stood, and started playing endgame moves with 191. Unbelievably, Iyama also thought that the marked stones were dead, so he too continued to play endgame moves. Both players were hallucinating.

The game continued up to move 225. The dame points were filled and the counting began. With both player tacitly agreeing that the marked stones were dead, Iyama took them off the board as his prisoners and won by 3½ points.

Perhaps the source of their hallucinations was the liberty at 'a'. If this liberty is filled by either side, Black's group is unconditionally dead.

Figure 2 (1–100)
Figure 2 (1–100).
Here are the first 100 moves of the game.

There is a Japanese proverb which says: Sara mo ki kara ochiru. (Even a monkey can fall from a tree.) Monkeys are skilled tree climbers and can swing effortlessly from branch to branch. But sometimes they miss and fall. And even top-ranked go players can misread a simple position.

Figure 3 (101–181)
Figure 3 (101–181).
Here are the moves that preceded Dia. 4.

Takao Shinji 9-dan, who did the commentary for the TV broadcast of this game, said that in his 30 years as a professional he had never seen anything like this.

After the game, Iyama told Cho U 9-dan that he was deeply upset by his oversight and felt that he had lost the trust of his go fans. He further told Cho that he was determined to win the final to regain their trust. And that is what he did when he forced Yuki Satoshi 9-dan to resign in 111 moves on October 27, 2022, to win the Ryusei title.

The move-by-move game record can be found at: Iyama versus Kato

Recommended reading
It cannot be overemphasized the importance of solving life-and-death problems if you hope to become a strong go player. Youngsters who aspire to become go professionals are required to spend many hours each day solving life-and-death problems to enhance their reading ability. This ability will pay rewards not only in quickly working out the solutions to life-and-death situations that arise in the corners and on the sides, but also in the fighting and skirmishes that pervade the game.

Two books on this topic appropriate for kyu-level players are Get Strong at Life and Death and 1001 Life and Death Problems. You will also find around 500 life-and-death problems in Volumes 3 and 4 of the Graded Go Problems for Beginners series

Once you have seriously worked your way through the above books, you will be ready to challenge the life-and-death and tesuji problems in the 'Graded Go Problems for Dan Players' series, namely 300 Life-and-Death Problems.