Is chasing a piece always illegal to repeat 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
No. Only a repeated, genuine threat to capture a specific piece counts as perpetual chase under the rules. If the supposed capture would not actually be profitable, or the piece is adequately protected in a way that makes the threat hollow, repeating the position is not automatically ruled against the chasing side.
Why the word 'genuine' does most of the work
The rules are not concerned with the appearance of a threat, only with whether capturing would actually gain something. A repeated approach toward a heavily defended piece, where taking it would simply lose material back, is not the kind of chase the adjudication targets.
Where the hard cases live
Whether chasing a soldier counts, whether a piece that could retreat to safety was really being chased, and how to rule when the chaser's own piece is also under threat are exactly the situations the 110-diagram casebook was built to settle, because no short verbal rule covers them cleanly.
Related questions
Does chasing an undefended piece always count?
Generally yes, if the capture would be a genuine gain and the position truly repeats.
Can a player claim their repeated moves were not really chasing?
Yes, and it is adjudicated on the actual position, not on either player's claimed intention.
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