Mate in 5 — Problem #12
Black to move — find the mate
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9
8
7
6
5
4
3
2
1
一
二
三
四
五
六
七
八
九
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Show solution
▲４二飛 △同 玉 ▲４三金打 △５一玉 ▲５二金打
Why this move works
The answer is ▲４二飛 △同玉 ▲４三金打 △５一玉 ▲５二金打. The key is the rook sacrifice: ▲４二飛 drags the king out to 4二, after which a ladder of golds anchored by the gold on 4四 hunts it down.
After △同玉, ▲４三金打 (defended by the 4四 gold) is a check the king cannot answer by capturing; the king runs with △５一玉, and ▲５二金打 (now defended by the 4三 gold) is the head gold. Giving up the rook to herd the king to the edge is the essence of five-move tsume.