What is a clearance sacrifice 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
Giving up material purely to get a piece out of the way of a square or a line that a different piece needs to use. It is common with a chariot pushing into enemy territory to open its own file for a second chariot, or a horse jumping into a square it will immediately lose, purely so that a cannon behind it gains a clear line.
Recognising the pattern
The giveaway is a piece moving to a square where it can obviously be captured, with no defensive purpose to the move at all. If that square or line becomes valuable to a different piece the moment the sacrificed piece leaves it, that is the whole idea.
It is a two-move tactic, not one
A clearance sacrifice only works if the follow-up move is ready to go immediately. Giving up the piece and then spending a move figuring out what to do next lets the opponent consolidate and simply keeps you a piece down. It shares its logic with any other sound sacrifice: know the follow-up before you give the material.
Related questions
Is this the same as a decoy?
Related but distinct: a decoy lures a piece onto a square, a clearance sacrifice removes a piece from one.
Which pieces use this most?
Chariots and cannons most often, since both need a clear line to work at all.
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