How the xiangqi cannon really works: it slides like a rook but leaps one screen to capture, plus the hollow-cannon and horse-and-cannon mates that win games.
The xiangqi cannon is the only piece that moves one way and captures another: it slides in a straight line like a rook when it's just travelling, but to take a piece it has to jump exactly one piece in between and land on the target beyond. That in-between piece is called the screen, and everything tricky about the cannon flows from it.
That split personality is why beginners keep losing pieces to a cannon they'd have sworn wasn't threatening anything — and why strong players seem to conjure attacks out of thin air. A cannon menaces squares it isn't even pointing at, cleanly, until you learn to count screens. Once you do, it becomes the most fun piece on the board. I'll cover how it moves, the famous opening built around it, the mates it delivers, and the one phase of the game where it quietly falls apart.
How the cannon moves and captures
Moving is the easy half. On an open line, the cannon slides any number of empty points along a rank or file, no different from a chariot. If it's not capturing, forget the screen entirely — it just glides.
Capturing is where you have to count. To take an enemy piece, there must be exactly one piece sitting between the cannon and its target. Zero pieces in between: no capture, the cannon can't reach through empty air. Two or more in between: also no capture. Precisely one, and the cannon leaps it and takes the target on the far side. The screen can be anything at all — your own Advisor, an enemy Horse, a stray Soldier, even the enemy General can be the piece you jump.
So a cannon controls a square only when the count between it and that square is exactly one. Pull the screen away and the threat evaporates. Slide a piece into the gap and a threat springs up the same instant. My advice: read every cannon on the board twice — once for where it can move, and a second, separate time, for what it can actually capture through its current screen. Those are two different maps.
The Central Cannon: the classic first move
The most popular opening move in the whole game is the Central Cannon — swinging a cannon onto the central file so it points straight down the board at the enemy General. The General starts on that file, and once a few pieces clear out, your cannon can use the General's own defenders as screens to punch into the palace.
It's direct and aggressive, which is exactly why tournament players have leaned on it for generations. The standard reply is the Screen Horses defense, where the second player brings out both Horses to protect the central Soldier and clog the cannon's firing line. If you learn just one opening clash, make it Central Cannon versus Screen Horses — it teaches the whole rhythm of cannon play: build a screen to attack, deny your opponent a clean line, and never let a central cannon sit there unchallenged.
The nightmare version is the hollow cannon, or empty-head cannon: a cannon on the central file with a totally open path to the enemy General and no screen in the way. It's one of the scariest sights in xiangqi. The General can't sit comfortably on that file anymore, and the attacker usually brings a Chariot along to finish the job.
Cannon tactics that actually win games
Cannons almost never checkmate alone — they do it with a partner. The most loved pattern is the horse-and-cannon mate, so common in Chinese that the phrase became an idiom for reacting a beat too late. You plant a Horse to cover the General's escape squares, then check with the cannon by jumping over that very Horse. The General can't run, because the Horse guards the exits, and it can't survive the check. Mate.
Then there are stacked cannons — two cannons lined up on the same file against the General, one acting as the screen for the other. That lets the pair deliver a check a single cannon never could, and against a General with just one defender they can strip the guards and mate with frightening speed.
And don't forget the flying-general rule, because cannons exploit it constantly. Since the two Generals can't face each other down an open file, a cannon that captures or lures away the one piece blocking that line creates an instant indirect threat — your own General does the 'attacking,' and enemy pieces on that file are frozen, afraid to move and expose their boss. Some of the prettiest cannon wins are really flying-general tricks in disguise.
The cannon's hidden weakness: the endgame
Here's what strong players know and beginners learn the hard way: the cannon is a middlegame monster and an endgame liability. In a bare endgame there's almost nothing left to use as a screen, so a cannon can aim at a target all day and never be able to touch it. A lone cannon often can't force mate against a well-defended General for exactly that reason — no screen when it needs one.
This is why the cannon-versus-chariot comparison matters. The Chariot only gets stronger as the board empties out; the cannon fades. So the practical plan almost writes itself: use your cannons early, in coordination, wring their value out of the crowded middlegame, and be willing to trade a fading cannon for a rising enemy Chariot or a key defender before you reach a thin endgame.
The players who truly master the cannon are the ones who feel its arc — dangerous while the board is full, patient once it thins out, and always thinking one screen ahead of everyone else.
Put the cannon to work
The fastest way to make the cannon click is to play it. Open your next game with a Central Cannon, go hunting for a screen you can build, and watch how just the threat of a hollow cannon shoves your opponent onto the back foot. Then play the other side and defend against one, so you learn to shut those firing lines down.
Start a live game or run a few tactics puzzles on XiangqiPlay and drill the horse-and-cannon and stacked-cannon mates until you spot them without thinking. Get the cannon under your fingers and you'll win games your opponents genuinely never see coming.