What is each piece's job in the opening?
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
Roughly: cannons claim lines and create the first threat; horses defend the central soldier and vacate files; chariots occupy the files the horses opened; soldiers move once, to free a horse; and advisors and elephants stay where they are unless there is a concrete reason.
Why advisors and elephants should not move
They cannot cross the river, so moving them gains no ground at all. All a quiet advisor or elephant move does is change which palace points are covered — and the point you vacate is very often the one the attacker needs.
The exception is moving one deliberately to remove a screen an enemy cannon is using.
The tempo test
Every move should bring something new into the game. If you have moved a cannon three times and both chariots are still at home, you are behind regardless of what the material count says — and the opponent who developed will show you why around move fifteen.
Related questions
Should I move the central soldier early?
Usually not. It weakens the point in front of your own general. The 3rd and 7th file soldiers are the ones that free horses.
How many opening moves should I know?
Four or five, plus the plan behind them. Beyond that, learn from your own games.
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