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# Sudoku Chess

This is a rules file for Zillions of Games, a Windows program that will let you play any puzzle or strategy board game you can feed it the rules to. With Zillions-of-Games installed, this rules file will let you play this game against your computer.

In January 2006 I saw a description of a Sudoku variant with Chess pieces. I decided to create a Chess variant with Sudoku characteristics. This Zillions file plays my attempt at a Sudoku-Chess hybrid.

Sudoku Chess is played on a 9-by-9 Sudoku board, solved or unsolved, agreed to by the players at the beginning. Each player has 9 pawns, 2 rooks, 2 knights, 2 bishops, 2 queens, and a king. Rules are the same as FIDE chess with the following exceptions:

• Pawns promote on the 9th row, not the 8th.
• In the initial setup, each player's first row has a queen on both sides of the king. The pieces on the first row are arranged in this order: RNBQKQBNR, where R = Rook, N = kNight, B = Bishop, Q = Queen, and K = King.
• Kings and rooks have the additional power to leap to any empty square in whichever 3-by-3 box they occupy.
• Knights and bishops have the additional power to leap to any empty square that has the same number as the square they occupy. (If the Sudoku is unsolved, the player needs to prove to the opponent or a referee that the destination square's number is the same as the origin's number.)

There are billions of possible "boards" for Sudoku chess. This Zillions file implements just two, and both of those are solved. Suggestions for improvement of the game or the script are welcome.