Can you checkmate with just a cannon in xiangqi?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
No. A cannon captures and checks only by jumping exactly one piece, and a bare general in an empty palace offers nothing to jump. A lone cannon cannot even give check, let alone mate. Add a single advisor as a screen and cannon-plus-advisor beats a bare general comfortably.
The endgame lesson
Do not trade your last advisor while your winning material is a cannon. The advisor is the cannon, functionally — it is the screen you control. Players convert cannon-and-advisor routinely and throw away cannon-alone routinely, and it is the same position one trade apart.
And the defensive one
If you are defending against a cannon, remove the screens. Trading or advancing every piece that could be jumped over — including your own elephants — is the standard defence, and against a lone cannon it turns a loss into a draw outright.
Related questions
What about two cannons?
Two cannons can mate, because each can screen for the other — that is the 重炮 pattern.
Cannon and soldier?
Wins, as long as the soldier is still on the board to act as a screen or cover a point.
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