Mate in 9 — Problem #3996310
🎯 Checkmate in 9 — your move
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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
▲８二龍 △７二金 ▲７三金 △５一玉 ▲８一龍 △７一金 ▲同 龍 △４二玉 ▲４一龍
Why this move works
The answer is ▲８二龍 △７二金 ▲７三金 △５一玉 ▲８一龍 △７一金 ▲同龍 △４二玉 ▲４一龍. With dragon and gold you keep checking, liquidating each defending gold while drawing the king in — a nine-move mate.
The finish is ▲４一龍: the king is confined to 4二 and cannot take the dragon, which the silver on 3二 defends. Even over a long line, the key is to keep checking every move while peeling off the defenders.