What is the strongest pin 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
A piece standing alone between the two generals. It is completely frozen — not merely inadvisable to move, but illegal to move, because every destination would leave the generals facing each other. It cannot capture, block or run, and the pinning piece is the enemy general, safely out of reach in its palace.
Turning it into material
A pinned piece is effectively undefended, because it cannot run and often cannot be helped. Two ways to cash in: attack it a second time, since it cannot move; or attack the point it stands on with a piece the defender cannot afford to trade.
Breaking out of one
Move your own general off the file — there is usually a spare palace point nobody looked for — or add a second piece to the line so neither is the only thing between the generals. Counter-attack works too, if it is faster than the threat.
Related questions
Can a pinned piece give check?
Not if it is pinned between the generals. Every move it has is illegal.
Do ordinary pins exist too?
Yes, against chariots and cannons. Cannon pins work backwards, because the pinned piece is the cannon's screen.
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