Can a soldier be the piece doing a perpetual chase 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
In principle, yes, any piece repeatedly threatening the same target can be a chaser. In practice it is rare, because a soldier's threat is usually so small that capturing whatever it is menacing would not be much of a gain, and the adjudication rules only care about genuine, profitable threats. A soldier shuffling near a chariot is unlikely to count as a real chase at all.
Why the soldier's low value works against it here
The whole basis for requiring a chaser to vary is that they are choosing to force a repetition for their own benefit. A soldier threatening a piece it could not actually win anything meaningful from, or that would simply be recaptured, does not create the kind of genuine choice the rule is built to police.
When a soldier chase could still count
If the soldier's threat is against something it genuinely could win, most plausibly another soldier or an undefended minor piece, and the position keeps recurring, the same principle applies as with any other chasing piece. It is the value of the threat that matters, not which piece is making it.
Related questions
Is this the same reasoning as chasing a defended piece not counting?
Yes, the same logic covered in why chasing a protected piece does not count applies here too.
Could a crossed soldier be a more credible chaser than an uncrossed one?
Yes, since a crossed soldier can threaten more directions and more valuable targets, making a genuine chase more plausible.
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