Can a soldier's one-way movement itself be the winning tactic, not just its support?
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
Yes. Because a soldier can never move backwards, forcing or inducing it forward, or sideways once it has crossed the river, can permanently close a line, seal a key square, or remove a defender's option in a way no other piece's move can, since every other piece can simply undo its own move later.
Why irreversibility is the actual weapon here
An ordinary piece that moves to block a line can retreat again next move if the situation changes; a soldier cannot. A tactic that induces an enemy soldier to advance into a square that permanently blocks its own defensive structure exploits exactly that one-way commitment, which is a genuinely different kind of leverage from anything a chariot, horse or cannon offers.
Where this shows up in practice
Offering a small bait that only a soldier can safely capture, knowing the capture permanently vacates a square the soldier was defending, or forcing a soldier sideways so it can never return to block a file again, are both real applications. It is a quieter, slower version of the more familiar idea in how a crossed soldier creates tactics, focused specifically on the permanence rather than the soldier's own attacking power.
Related questions
Does this apply before a soldier crosses the river too?
Yes, the irreversibility exists from the soldier's very first move, though the sideways option that opens up new tactical uses only exists after crossing.
Is this a common tactic or a rare one?
The underlying idea is common in a quiet, structural way; it is rarely the single dramatic move of a combination but often a small, permanent gain worth watching for.
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