How do I play chariot and cannon against a lone chariot?
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
Use the extra piece to create a second problem, rather than trading it away for a simpler position. Chariot and cannon against a lone chariot is a material advantage that should win with care, and the practical method is coordinating the two attackers so the defending chariot cannot cover both threats at once, similar in spirit to how chariot endgames tend to play out.
Do not rush to simplify
Trading chariots leaves your cannon on its own, and a lone cannon cannot force mate even against a bare general. Keep both attackers unless a specific, calculated line justifies the trade.
Coordinate rather than attack separately
A cannon needs a screen, so plan where that screen comes from before committing the attack, and use the chariot to either provide it or to create the second threat the lone defending chariot has to choose between.
Related questions
Is this always winning?
With correct technique it should usually win, though a well-defended lone chariot can make it take real work.
Should the cannon or chariot lead the attack?
Usually the chariot, since it threatens directly; the cannon supports once a screen is available.
.