The Chess Variant Pages

Check out Hectochess, our featured variant for November, 2023.

This page is written by the game's inventor, A. M. DeWitt. This game is a favorite of its inventor.


Hectochess is a game inspired by my earlier game Yangsi. The idea for the game came about when I realized that Yangsi had 4 too many pieces to be played with just a 10x10 chessboard and 2 mismatched chess sets. I decided to make a similar game that could be played using said equipment. The result was Hectochess. The idea was not to make an entirely new game, but rather to make a more accessible version of Yangsi.


An interactive diagram has been provided (The Javascript source code was written by H. G. Muller) to make it easier to understand how each piece moves. The diagram uses pieces from the Musketeer Chess Board Painter.

First rank

Second rank

Third rank


Upside down pieces are pieces from a second Chess set whose pieces are visually distinct from the first Chess set.

The King moves one space in any direction but not into check. It moves the same as it does in Chess but castles differently.
The Queen moves as a Rook or a Bishop, the same as it does in Chess.

The Marshall moves as a Rook or a Knight. It is a popular piece in many Chess variants, dating back centuries, even before Chess as we know it today came into existence.

The Archbishop moves as a Knight or a Bishop. It is a popular piece in many Chess variants, dating back centuries, even before Chess as we know it today came into existence.

The Rook slides across the board in a vertical or horizontal direction, as it does in Chess.
The Bishop slides across the board in any diagonal direction, as it does in Chess.

The Knight leaps to a space one file and two ranks away or two files and one rank away, as it does in Chess.
The Pawn moves one space vertically forward without capturing, and it moves one space diagonally forward to capture, as it does in Chess. It can also move two squares forward on its first move and capture by en passant a Pawn that has just made a double move like it does in Chess. However, it is subject to different rules of promotion.

The Champion leaps two spaces in any orthogonal or diagonal direction, or one space in any orthogonal direction. It is a compound of the Alfil, Dababbah, and Wazir. It was introduced in Omega Chess, and it moves the same as it does in that game.

The Wizard moves one space diagonally or leaps to a space one file and three ranks away or three files and one rank away. It is a compound of the Ferz and the Camel. It was introduced in Omega Chess, and it moves the same as it does in that game.

The Leo moves as a Queen but must hop over an intervening piece to capture.    


Aside from differences in the board, pieces, and setup, Hectochess is played like FIDE Chess with the following differences:

Pawn promotion: When a Pawn reaches the last rank, it must promote to another piece of that player's choice: a Queen, Marshall, Archbishop, Rook, Champion, Leo, Knight, Bishop, or Wizard of the same color. It cannot promote to King or another Pawn.

Castling: When castling, a King may move two or three spaces toward the Rook when it castles, with the Rook leaping over the King to the closest space the King has just passed over, so that King and Rook end up adjacent to each other. The usual castling conditions from Chess apply. A King may not castle from or through check, all spaces between the Rook and King must be empty, and neither piece may have moved before.

64-move rule: The 50-move rule from Chess becomes a 64-move rule in Hectochess. Similarly, the lesser-known 75-move rule from Chess is a 96-move rule in Hectochess.


Other than the difference in the setup and the fact that the Cannons and Vaos have been replaced by Leos, Hectochess uses the same rules as Yangsi. I replaced the hoppers from Yangsi with Leos because I wanted to include their moves but I only had one other piece type available due to my objective of making it playable with two mismatched chess sets.

Game Courier Tournament 2019

Hectochess was selected by Greg Strong as one of the nine games to be played in the Game Courier Tournament 2019. Hectochess was played in Round 3 of the tournament, along with Symmetric Chess and Metamachy.

On a side note, Hectochess is the only third round game in this tournament which already had presets with full rule enforcement and display of legal moves by the time the first round began. At the time Fergus Duniho was working on rule enforcement for the presets, which are now finished. The reason Symmetric Chess and Metamachy were placed in the third round was to give Fergus as much time as possible to complete the presets. As for why Hectochess was placed in the third round, that's just how it played out.

Similar Games

Computer Play

You can Play Hectochess online with Game Courier.

This 'user submitted' page is a collaboration between the posting user and the Chess Variant Pages. Registered contributors to the Chess Variant Pages have the ability to post their own works, subject to review and editing by the Chess Variant Pages Editorial Staff.

By A. M. DeWitt.

Last revised by A. M. DeWitt.

Web page created: 2019-01-02. Web page last updated: 2019-03-08