How do I open a file for my chariot?
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
Move the piece that is standing on it. Usually that is the horse — developing a horse vacates the file behind it — or the cannon, which often swings to the centre and leaves its own file clear. Advancing the soldier on the file works too. The important part is deciding which file before you need the chariot.
The usual sequence
Cannon takes the centre, horse develops and frees a file, chariot slides onto it. Three moves, and by move six the chariot has somewhere useful to be. Systems differ in detail, but almost all of them follow this dependency.
Do not move the chariot before the file exists
A chariot shuffling along the back rank looking for work is a wasted tempo. Open the line first; the chariot takes one move to arrive once there is somewhere to go.
Related questions
Which file is best?
Usually one adjacent to the centre, where it supports an attack on the palace. The outermost files are the least useful.
Should both chariots get files?
Ideally. Doubled chariots on one file are also very strong, which is the basis of 雙車錯.
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