Why do red and black use different characters 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
So you can tell the armies apart at a glance. Six of the seven types differ: 帥/將, 仕/士, 相/象, 傌/馬, 俥/車, 兵/卒. They are homophones or near-homophones and the pieces move identically — it is a visual convention, not a rule difference.
The pattern behind the pairs
Red's characters tend to be the more formal or military-flavoured ones: 帥 (marshal) against 將 (general), 仕 (officer) against 士 (scholar), 兵 (soldier) against 卒 (conscript). Several of Red's take the 人 radical — 傌, 俥 — which is a quick way to recognise the side.
The cannon is the inconsistent one
炮 and 砲 are both used, and which side gets which varies between manufacturers and books. 砲 has the stone radical (older siege engines threw rocks); 炮 has the fire radical (gunpowder). Nothing about play changes either way.
Related questions
Do the different characters move differently?
No. The pairs are purely cosmetic.
Which colour is 帥?
Red, conventionally. Black's general is 將.
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