Do you have to announce check in xiangqi?
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
No. There is no requirement to announce check (將軍), and in tournament play it is not done. The responsibility for noticing sits entirely with the player being checked. Casual park games often announce it loudly, but that is sociability, not rules.
What happens if check is missed
A move that leaves your own general in check is illegal, so it simply cannot stand. In a formal game an arbiter has the move retracted and a legal one played instead, with a penalty possible for repeated illegal moves. Online, the board refuses the move outright.
The check that gets missed most
Discovered check from a cannon, because the line was empty a moment earlier and did not look like an attack. The habit that prevents it: after your opponent moves, check every cannon on a line with your general, and count the pieces in between.
Related questions
Is there a penalty for an illegal move?
In formal play, yes — typically a warning, with repetition leading to loss. Casual play just takes the move back.
Must I announce checkmate?
No. The game simply ends when there is no legal reply.
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