How many pieces do you need to attack 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
At least two, and usually exactly two. One attacker is answered by one defender and nothing happens — you have spent a move and gained nothing. Nearly every named mating pattern in xiangqi uses precisely two attacking pieces, which is both the minimum and, in practice, the requirement.
Why two is enough here
Because the palace is nine points and the defender's own advisors and elephants occupy some of them. One piece checks, the other covers the escapes. In chess you often need three attackers because the king can run; here it cannot.
Counting before you commit
Two numbers: how many pieces you can bring to the palace in three moves, and how many the defender can bring back. If theirs is larger, the attack is not ready and striking now just gives them a free tempo.
Your own general counts as an attacker in simplified positions.
Related questions
Can one piece ever mate?
A chariot can mate a bare general — with your own general's help, which is the second attacker.
Is three attackers better?
Yes, but it usually costs too many moves. Two arriving quickly beats three arriving late.
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