What is 窩心馬, a horse in the palace heart?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws for movement, checkmate and both repetition rulings: a side that forces a repetition by perpetual check or perpetual chase loses rather than drawing. The chase half has not been validated against the official casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it before publishing.
Direct answer
窩心馬 is a horse standing on the centre point of its own palace. It is a well-known bad shape: the horse takes the general's most important square, blocks the centre file, and has trouble getting out again because its legs are easily blocked by its own advisors and elephants.
Why it happens
Usually as a defensive retreat. A horse drops back into the palace to cover a point, block a check, or stop a cannon on the centre file. In the moment that can be the only defence, and sometimes it is correct. The trouble comes after.
What it costs
The general loses its central point, so it has fewer escape squares and the advisors lose room too. A horse on the palace centre also sits on the centre file, where it may become the screen an enemy cannon needs to give check. And getting it out takes time: the legs point into advisors, elephants and the general itself, so the horse may need several moves just to rejoin the game. Meanwhile it is not attacking anything. See how many escape points a general has.
How to avoid or fix it
Prefer defences that keep the horse outside the palace: block with a soldier or elephant, move the general, or counterattack. If the horse is already there, plan its exit early, usually by moving the advisor or elephant that blocks its leg first. Common mistakes lists similar self-blocking habits.
Related questions
Is an enemy horse on my palace centre dangerous?
Very often, yes. An attacking piece on the palace centre takes points from your general; see the palace heart.
Is a cannon in the palace centre also bad?
It raises similar concerns about blocking the general, but each case depends on the position.
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