Of all xiangqi rules, the one that feels strangest to newcomers is the flying general rule: the two generals may never stand on the same file with nothing between them. It sounds like a footnote. In practice it shapes every endgame and decides a surprising number of middlegames, because it turns your general — a piece that never leaves its palace — into a long-range attacker.
This article explains the rule precisely, shows which moves it forbids, and then shows how to use it.
The rule in one sentence
A move is illegal if, after it, the two generals stand on the same file with no piece between them.
It does not matter which general "moves into" the line. It does not matter whether the piece that leaves the file is yours or the opponent's. What matters is only the position after the move.
The Vietnamese name is lộ mặt tướng ("the general shows its face"), and the famous mating pattern built on it is called bạch diện tướng — "white-faced general".
Another way to see it: the general "attacks" along the file
The easiest mental model is this: treat each general as if it attacks the whole file in front of it, up to the first piece, like a chariot pointing straight ahead.
With that model, the rule behaves exactly like check:
- The enemy general cannot step onto a point on your general's open file, because it would be "in check" from your general.
- You cannot move the last piece standing between the two generals, because that would expose your own general to "check" from the other one.
Everything below follows from this picture.
Moves the rule forbids
1. Stepping the general onto the open file
If your general stands on the center file and the file is open all the way to the other palace, the enemy general cannot step onto that file. In the endgame this often takes one or two escape points away from the defending general — which is frequently the difference between a draw and a loss.
2. Moving the last blocker
Suppose the two generals are on the same file and a single piece stands between them. That piece is pinned: it may move along the file, but it may not leave it. This is true even if the piece belongs to the side that is not under any threat. Pinned blockers are a common source of beginner surprises: "why can't I move my horse?"
3. Escaping check onto the file
When your general is in check and you consider stepping sideways, look first at the other general. The sideways point may be on the enemy general's open file, which makes it illegal.
The rule as a weapon: white-faced general mates
The most important practical use is in checkmating patterns. Your general controls a file without moving, so a single attacking piece is often enough.
Notice how little material Red needs. In chess, a lone rook plus king needs careful technique to mate. In xiangqi, the general's control of the center file makes many such positions instant.
The same idea works without check. A general with no legal move loses in xiangqi, so squeezing the enemy general can be enough:
Practical habits
Put your general on a useful file in the endgame
In many endgames the winning plan starts with the attacker's general stepping to the side file, for example from the center to one of the side files of the palace. From there it takes away escape points on that file. Strong players move the general early in the endgame for exactly this reason.
Keep a blocker in front of your own general when you defend
When the enemy general stands on your file with only one piece between, that piece is pinned and cannot help elsewhere. If you have a choice, avoid placing your general on the same file as the opponent's general with a single blocker in between.
Watch for discovered "checks" from the general
When a piece moves off the file between the two generals, that is illegal. But when a piece moves off the file between your general and an empty stretch in front of the enemy palace, your general suddenly controls points it did not control before. Use this: moving a horse or chariot off the center file can take escape squares away from the enemy general at the same moment it creates a threat elsewhere.
Common misunderstandings
"The generals can face each other if it is not check." No. Facing is illegal in every case, whether or not anything else is attacking.
"Only the player whose move creates the facing is at fault." The rule is simply about legality: you cannot make any move that leaves the generals facing. If your move would do it, you cannot make that move.
"A general can capture the other general along the file." Casual players sometimes play it this way as a shortcut: if the opponent leaves the generals facing, you "fly" across and capture. In proper play the facing move is simply not allowed. On this site the move is refused.
How it compares to chess
In chess, two kings can never stand on adjacent squares, but they can see each other across the board. In xiangqi, the generals are confined to their palaces and could never come close — so instead the rule works at long range. For chess players this is the single most important "new geometry" to absorb. More differences are collected in the rules overview.
Try it yourself
Set up a simple endgame on the home page and play the computer: try to checkmate with a single chariot while your general holds the center file. After two or three attempts you will start seeing the general as an attacking piece.
Frequently asked questions
Is the flying general rule used in all xiangqi rule sets?
Yes. It is a basic rule of xiangqi everywhere, not a local variation.
Can the generals face each other if a cannon is between them?
A cannon between them is a blocker like any other piece, so the generals are not facing. Be careful though: that cannon cannot leave the file.
Does the rule work in the middle of the board?
The generals never leave their palaces, so the only files where they can face each other are the three palace files. Most of the time it is the center file.
What happens if I try to make an illegal facing move online?
The move is simply not accepted. You will need to choose a different move.
