Illegal Moves in Xiangqi: Every Rule You Must Know

The palace: where the General and Advisors must stay

Each side has a palace (九宫, traditional 九宮, jiǔgōng), a 3x3 block of nine points marked with diagonal lines in the middle of its back edge. The General and both Advisors are confined to it. Any move that would take one of them outside, even by a single point, is illegal.

Inside the palace the two kinds of piece move differently. The General steps one point horizontally or vertically, never diagonally, even though the diagonal lines are drawn right beside it. The Advisor steps one point diagonally along those lines, so it can only ever occupy five points: the four corners and the center. Moving the General diagonally or an Advisor straight is a classic beginner slip.

Facing Generals and moves that expose your own General

The two Generals may never stand on the same file with nothing between them. This is usually called the flying general rule, because it is equivalent to saying that a General could fly straight down an open file and capture its counterpart. Any move that creates that position is illegal, whether you step your General onto the open file or move away the last piece standing between the two.

That makes a lone piece between the Generals effectively pinned. A Chariot, Cannon, or Soldier in that spot may still move along the file as long as it stays between them, but it cannot step off the file, and a Horse, Elephant, or Advisor there cannot move at all without exposing the Generals.

More generally, no move may leave your own General in check. You cannot ignore a check, you cannot move a piece that is shielding your General from an enemy Chariot, and you cannot step your General onto a point an enemy piece attacks. Remember that a Horse only attacks through an open leg. The Cannon adds two twists. Moving one of your pieces onto an empty line between an enemy Cannon and your General creates a screen and hands the Cannon a check, so that move is illegal. And if two pieces stand between the Cannon and your General, moving one of them away leaves exactly one screen, which is also check.

The Elephant: no river crossing, no blocked eye

The Elephant moves exactly two points diagonally, no more and no less. It may never cross the river, so it stays on its own half of the board and can reach only seven points in total. A move that would carry it over the river is illegal, however tempting the target on the other side.

The Elephant is also blocked if the point midway along its diagonal is occupied by any piece, friendly or enemy. Chinese players call this blocking the elephant's eye (塞象眼 sāi xiàng yǎn). With the eye filled, the move is illegal even if the destination point itself is empty. That is why a single well-placed piece can freeze an Elephant in place without ever attacking it.

The Horse: no move over a hobbled leg

The Horse moves one point horizontally or vertically, then one point diagonally away from where it started. If the first point, the one directly beside the Horse in the direction it wants to go, is occupied by any piece, that whole path is blocked. This is called hobbling the horse's leg (蹩马腿, traditional 蹩馬腿, bié mǎ tuǐ).

Only that adjacent point matters, and your own pieces block it just as effectively as the enemy's. Unlike a chess knight, the Horse cannot jump over whatever stands in its way. Because a leg can be blocked in one direction and open in another, Horses do not always attack each other symmetrically: your Horse can attack an enemy Horse that cannot hit back, because its leg in that direction is blocked and yours is not. Check the leg every time, both when you attack and when you think a point is safe.

The Chariot, the Cannon, and the Soldier

The Chariot moves any number of points along a rank or file. It cannot jump, so it may not pass through or over any piece, and it captures the first enemy piece in its path. Beyond that it has no restrictions: it may cross the river and go anywhere on the board.

The Cannon moves exactly like a Chariot when it is not capturing, and a non-capturing Cannon may not jump over anything. To capture, it must jump over exactly one piece of either color, called the screen or cannon mount (炮架 pào jià), and land on the enemy piece beyond it. Any number of empty points may lie before and after the screen. Capturing with no screen is illegal, and so is jumping two pieces. A Cannon lined up on an enemy piece with nothing in between cannot take it.

The Soldier moves one point straight forward until it crosses the river. After crossing it may move one point forward or one point sideways. It may never move backward or diagonally, and it does not promote when it reaches the far edge, where it can only move sideways. A sideways step before the river is an easy illegal move to attempt by accident.

Forbidden repetitions and chess rules that do not exist

Some moves are legal on their own but illegal as a pattern. Perpetual check (长将, traditional 長將, cháng jiāng), giving check on every move of a repeating cycle, is forbidden, and so is perpetual chase (长捉, traditional 長捉, cháng zhuō), threatening the same piece, usually an unprotected one, on every move of a cycle. Under competition rules the side doing it must change its move or lose. The rule books of the Asian Xiangqi Federation and the Chinese Xiangqi Association differ in the fine print, and our guides to perpetual check, perpetual chase, and xiangqi draw rules cover the details.

Several things chess players take for granted simply do not exist. There is no castling, no promotion, no en passant, and no double-step for Soldiers on their first move. You cannot pass either: if it is your turn, you must move. And if you have no legal move at all, you do not escape with a draw. Stalemate in xiangqi is a loss for the player who cannot move.

A quick self-check before every move

Run through four short questions before you commit. First, the zone check: is the piece allowed on its destination? The General and Advisors stay in the palace, the Elephant stays on its own side of the river, and a Soldier that has not crossed the river only moves forward.

Second, the path check: is the way clear? Look at the Horse's leg, the Elephant's eye, and every point along a Chariot's line. For a Cannon capture, count the pieces between it and the target and make sure there is exactly one.

Third, the General check: after this move, is your General safe? Scan the files and ranks for enemy Chariots, count the screens in front of enemy Cannons, look at which enemy Horses have open legs, note any enemy Soldiers beside your palace, and confirm the two Generals are not facing each other on an open file.

Fourth, the repetition check: have you already played this check or this threat in the same position? If so, look for a different plan before the loop hands your opponent the game. After a few dozen games these four questions take a second, and illegal moves disappear from your play.

Practice on XiangqiPlay

The fastest way to absorb these rules is to play. On XiangqiPlay the board only accepts legal moves, and selecting a piece marks every point it can legally reach, so you can see at once what a hobbled Horse, a hemmed-in Elephant, or a screened Cannon really has. Play the computer at beginner, intermediate, or advanced level, or challenge a friend. Playing requires a free account.

Then test your eye in the free puzzle library of 5,000 engine-proven mate puzzles. Mating patterns often turn on exactly these restrictions: a hobbled Horse that cannot defend, an Elephant with a blocked eye, or a General held in place by its counterpart on an open file. Spotting them quickly is what turns knowing the rules into winning games.