What is 反宮馬 (the Reversed Palace Horse)?
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
反宮馬 is a defence to the Central Cannon in which both horses come out and a cannon goes to the advisor's corner, between them, rather than to the centre or a wing. It is a close relative of Screen Horses: the extra defender makes the structure very solid and hard to attack, at the cost of being slower and more cramped.
Why put the cannon between the horses
In Screen Horses the two horses defend each other, so blocking one horse's leg or deflecting the piece behind can break the defence. 反宮馬 adds a defender that is not a horse: the cannon at the advisor's corner covers both horses, so a move that blocks a leg does not also remove the defence. The price is a move of time, and a cannon standing in its own pieces' way.
Who tends to play it
Players who like Screen Horses but keep losing a horse to the same trick often try it next. Red usually tries to attack before the structure is complete; once both horses and the cannon are in place, the position is hard to break down and the game becomes a long manoeuvring fight.
Related questions
Is 反宮馬 only for Black?
It is most common as a defence, but the same idea appears in some Red systems too.
Is it more passive than Screen Horses?
Slower and more cramped early on, not passive overall. Both horses still reach useful squares within a few moves.
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