Should I develop my horses or my cannons first?
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
Whichever piece creates a threat moves first; the piece answering it follows. In most mainstream openings that means a cannon goes to the centre before the horses develop, because the cannon's move is what forces a reply. Playing a system out of that order usually just loses the tempo the opening was built to gain.
Why the cannon usually leads
A cannon on the central file threatens the opponent's central soldier immediately, which is what makes a reply necessary. A horse developed first threatens nothing comparable, so it invites the opponent to develop freely instead of answering a threat.
Where horses genuinely go first
In quieter systems, such as 飛相局, there is no early threat to create, so there is no strict order to respect. There, develop whichever piece improves your position most and keep both chariots' files in mind.
Related questions
Does the order really matter that much?
Against a strong opponent, yes. A wasted tempo in the opening is often the first domino in a lost game.
What about the cannons not going to the centre?
Those can wait. Only the cannon making the immediate threat needs to move early.
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