The Palace-Corner Cannon

Why take a cannon across the palace?

The move gathers both of Red's cannons on one side of the board. Red plays 炮二平六 (C2=6), or 炮八平四 (C8=4) from the other wing. On this page the cannon goes from h2 across the front of the palace to d2. The board below marks it with a ring, together with the cannon on b2.

The move also helps the horse come up and the chariot come out, so Red's main pieces get into play quickly. The board shows both on the wing that the cannon has left: the horse comes out from h0 to g2, and the chariot steps from i0 to h0.

The palace-corner cannon is one of the more common cannon openings, along with the advisor-corner cannon. In the ECCO, the Chinese system of opening codes drawn up in 2004, it has the codes A60 to A65.

The course line, move by move

The board plays the line that Xiangqi Arena's opening course teaches for the palace-corner cannon. It starts with the opening's standard move, and a computer engine continued it from there. As you step through it, watch the h-file.

From Red's third move on, Red's chariot on that file attacks Black's cannon on h7, and Black's chariot guards the cannon from h9. The line on the board ends on the other wing, where Black's chariot attacks Red's cannon on b2.

How does Black answer?

The board below starts after 炮二平六 (C2=6), a position that 770 archive games reached. It shows the three replies Black chose most often there: 马8进7 (H8+7), 炮8平5 (C8=5) and 卒7进1 (P7+1). The first two are usual replies to the palace-corner cannon, and so is the horizontal chariot (横车, hengju), 车9进1 (R9+1).

Of the archive's three named lines below, two continue after the horse move to g7 and one after the central cannon. Black chooses those two replies most often, so as Red, prepare for them first.

The plan and the principles

The main idea of the palace-corner cannon is to gather force and attack one of the opponent's wings. It works for attack and for defence, and strong players use it well. Against it, a chariot that Black brings out carelessly often comes under attack.

Xiangqi Arena teaches five principles for the opening: bring the chariots out quickly, do not move one piece again and again, do not grab soldiers, keep both wings in balance and do not expose the general. You can see the first three in the course line. Within six moves each side brings out both horses and a chariot, nothing is captured, and the only piece that moves twice is Red's chariot, from i0 to h0 and later to h4.

Common mistakes

Some players follow the first move with more cannon moves, and the horse and chariot on the right stay at home. The first move is there to let those pieces out quickly, and every extra cannon move keeps them waiting while Black develops. In the course line the horse comes to g2 on Red's second move and the chariot to h0 on the third, where it attacks Black's cannon on h7 at once.

Black often answers the first move with a central cannon, 炮8平5 (C8=5), one of the three replies Black chooses most. From e7 that cannon attacks your soldier on e3 over Black's own soldier on e6. If your second move leaves the soldier unguarded, the cannon can take it for free. In the archive's line against the left central cannon, Red's second move is the horse to g2, which guards the soldier and brings out a piece at the same time.

As Black, pay attention to the h-file. Once Red's cannon has left h2 and Red's chariot reaches h0, it attacks your cannon on h7, and in the course line only your chariot on h9 guards it. If that chariot moves away, Red's chariot can take the cannon for free. The archive's lines show two ways to settle the file: the cannon steps aside to i7 to bring out the chariot, or it advances to h3 and blocks Red's chariot.

The palace-corner cannon in the archive

The archive holds 770 games that open with the palace-corner cannon, out of 29,164 games between human players. Red wins 34% of them, 41% end in a draw and Black wins 25%. A game lasts 46 moves on average.

Across the whole archive, Red wins 37% of the games and 36% are drawn, so you can compare the opening's results with the average game. Hong Zhi chose the palace-corner cannon most often as Red, in 31 games, and Lü Qin met it most often as Black, in 20 games. You can look up both players' games in the archive and play through them.

An old opening and a Qing manual

The palace-corner cannon is an old opening. The Qing manual 梅花谱 (Meihuapu), one of the two famous classical manuals of xiangqi, studies it together with the same-direction and opposite-direction cannons and the screen horses against the central cannon. Its author, Wang Zaiyue (王再越), lived in the Kangxi era.

Under the Qing the manual was not printed. It circulated in handwritten copies until a lithographed edition appeared in 1917 and a typeset edition in 1926. One of its chapters, 当头炮破过宫炮 (dangtoupao po guogongpao), gives five games in which the central cannon defeats the palace-corner cannon.

To make the opening your own, step through the course line until the moves come easily. Then practise it in the course's drills: in one you play Red's moves yourself, and in the other you defend against the opening as Black. After that, try it in a few games against the computer. It will not win games by itself, but it brings your pieces out quickly.