What is Screen Horses (屏風馬)?
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
屏風馬 — "folding screen horses" — is the standard answer to the Central Cannon. Both horses come to the points beside the central file, defending the central soldier and standing side by side like a screen. It defends and develops with the same moves, which is why it is the most played defence in the game.
Why it answers the Central Cannon so well
A Central Cannon's first threat is the central soldier. 馬8進7 defends it and develops a piece, so Black loses no time answering — which is the whole problem with every other reply. The second horse follows, and Black has two developed pieces and a solid centre.
What comes after
Black opens a file for a chariot and contests the centre. The resulting middlegames are the most heavily analysed in xiangqi, and they are the reason this pairing is what most players should learn first: between Central Cannon and Screen Horses you learn both how attacks are built and how they are stopped.
Related questions
Is Screen Horses only for Black?
It is usually Black's defence, but the same formation is playable for Red in some systems.
What is the alternative defence?
Answering with a central cannon of your own, giving 順炮 or 列炮.
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