Chess 960 or Fischer-Chess or Full Chess

With File arrow New - Fischer Chess or with a click on the right mouse button on the chessboard-symbol ( [schachbrettsymbol256.bmp] ) in the tool bar you start a new Chess 960 game. You can also choose a Chess 960 position in the "Set up a position"-dialogue if you would like to play a specific starting position.

This is a chess variant introduced by the former world champion Bobby Fischer. Nowadays its called Full Chess or Chess960 because of the number of different starting positions, which is of course 960.

The starting position of a Fischer game is changed randomly so that the pieces are on a different starting square than usual. The position of the pawns remains unchanged. The two bishops must stand on squares with different colours.

Example of a Chess 960 position:

[schach960.bmp]

Chess 960 has the advantage of making specialised opening knowledge worthless. From the first move on the players have to think on their own now. Tactical problems often occur in the very first moves. So be careful against the chess engines!

In a Chess 960 game the king has to be placed between the two rooks to make the extended castling possible. The two small dots (here in the c and g-file) under and above the chessboard indicate castling availability.

Castling works as follows:

No matter where king and rook stand before castling, their target squares are the same as in normal chess. For king side castling the white rook is on f1 and the white king on g1 after castling. For queen side castling the white rook is on d1 and the white king on c1 after castling. The terms king side and queenside make no sense in Fischer chess, so the terms a-side and h-side castling should be used.

To castle, just move the king or the rook, the move of the other piece will be made automatically. Be careful, especially with the rook: In many cases the rook move could be legal by itself (so might be the king move). To distinguish between a normal move and castling press Ctrl on the keyboard while you make the move with the mouse. You only need to press Ctrl if you must distinguish between castling and normal move.

Sometimes the king remains on the same square in the castling move. In this case you have to move the rook.

Castling seems complicated, but practice shows that it is understood intuitively.

The main difference to Shuffle Chess is that Shuffle Chess doesn't know about castling.

You can also determine in the Board set-up dialog if you want to play Fischer Random Chess from a position you manually set up.

Arena can read Fischer Random Chess Games in PGN format.

Engine support:

Because Chess 960 is played with a different starting position, the engines have to support this. WinBoard engines need to support the edit mode, UCI-engine the "startpos FEN" command.

There are currently not many engines that fully support Chess 960. The problem lies in the correct execution and recognition of the extended castling move. Therefore an appeal to all engine programmers: Support Fischer Random Chess! Arena transmits and receives the castling moves in Fischer chess (and only there!) always in the form "O-O" for h-side castling or "O-O-O" for a-side castling (the letter 'O' is used, not the number '0').This applies both to the WinBoard and UCI communication.