Kriegspiel (chess) illegal, the player tries again; if it is legal, that move stands. Each player is given information about checks and captures. They may also ask the referee if there are any legal captures with a pawn. Since the position of the opponent's pieces is unknown, Kriegspiel is not a game with perfect information. As each player cannot see his opponent's pieces, the game is sometimes referred to as "blind chess". There are several different rule sets for Kriegspiel. The most widespread rules are those used on the Internet Chess Club, where Kriegspiel is called "Wild 16". The rules are as
Infinite chess game called Courier chess was played on a slightly larger 12×8 board (96 squares) in the 12th century, and continued to be played for at least six hundred years. Japanese chess (shogi) has been played historically on boards of various sizes; the largest is taikyoku shōgi ("ultimate chess"). This chess-like game, which dates to the mid 16th century, was played on a 36×36 board (1296 squares). Each player starts with 402 pieces of 209 different types, and a well-played game would require several days of play, possibly requiring each player to make over a thousand moves. Chess player Jianying Ji