Gustavian Cannonrider Chess

invented and implemented July 2006
by Mats Winther

See also my homepage.

In Gustavian Cannonrider Chess "Cannonriders" are initially positioned on the Bishop files. The Cannonrider moves differently depending on the colour of the square. On black squares it moves like a Cannon: it slides like a Rook, but can capture an enemy only if there is another piece (of either side) in between, and any interim squares are empty. Thus to capture it leaps over the intervening piece and lands on the enemy piece, like a cannonball. If positioned on a white square it jumps like a Nightrider, that is, can make continuous knight jumps in the same direction, provided that the interim squares are empty. Otherwise, the rules are the same as in standard chess, except for the possible pawn promotion to Cannonrider. The Cannonrider's value is 5, that is, the same as a Rook. The Cannonrider's image also changes when it moves to a square with a different colour (it rotates). This makes it easier to understand the piece. Note that the Kings are initially positioned on the d-file.

The Cannonrider is a very interesting piece for the tactician. Positionally, too, it could be quite dangerous because one can sometimes sacrifice a Cannonrider for a light piece (Knight or Bishop) to achieve positional ends. In the middlegame the Cannonrider is more valuable than a Rook, due to its dangerous tactical capabilities. But in the endgame it is less valuable than a Rook. An obvious case is the endgame King + Cannonrider vs. King, while it cannot give mate to the enemy King.

The board type was invented by Gustav III of Sweden (1746-92) for his own chess variant "Gustav III's Chess". The Gustavian board makes it possible to place additional pieces on the board without substantially increasing the board size. This often means that a strategical and tactical intensity is maintained. Gustav III's Chess has also been implemented in Zillions.



The Cannonrider, standing on a white
square, can jump like a knight, but
also has the continuous knight jumps.



The Cannonrider, standing on a black
square, can slide like a rook. But it
can only capture by jumping over any
intervening piece and landing on an
enemy piece.

There is also a variant where Scorpions take the place of the pawns. The Scorpion has the additional moves of a Knight, but only in two forward directions: east-north-east, and west-north-west. There are no additional capture moves.The Scorpion's value is half the value of a Knight or Bishop, that is, 1.5. This means that a light piece can be exchanged for two Scorpions, a possibility which often occurs. In the endgame it could become very dangerous, and its value often increases.)



The two oblique moves in the image
are the Scorpions two extra movement
possibilities. It can only capture like
a regular pawn.



Gustavian Cannonrider Chess, and the Cannonrider piece, were invented by undersigned, July 2006. The Cannon movement derives from the Cannon in Chinese Chess (Xiangqi). The Nightrider movement was invented by the British chess problem composer T.R. Dawson. The Scorpion pawn derives from my Scorpion Chess. Try playing Gustavian Cannonrider Chess by e-mail, against a human opponent, at Chessvariants.org.

To play you must have installed "Zillions of Games". Either double-click on GustavianCannonriderChess.zrf or
1. Run "Zillions of Games"
2. Choose "Open Game Rules..." from the File menu
3. Select "GustavianCannonriderChess.zrf" in the Open dialog and click "Open"
GustavianCannonriderChess.zrf is a rules file used by the Windows program "Zillions of Games". Zillions of Games allows you to play any number of games against the computer or over the Internet. Zillions of Games can be purchased online. For more information please visit the Zillions of Games website www.zillions-of-games.com