Mate in 1 — Problem #5
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
▲６二金
Why this move works
The answer is the head gold ▲６二金. The silver directly behind it on 6三 protects the gold, so the king cannot capture it.
The gold seals all four escape squares (5一, 7一, 5二, 7二), and the edge-bound king has no upward escape. Mate.