Chess with different armies

Chess with different armies (or Betza's Chess or Equal Armies) is a chess variant invented by Ralph Betza in 1979. Two sides use different sets of fairy pieces. There are several armies of equal strength to choose from, including the standard FIDE army. In all armies kings and pawns are the same as in FIDE chess, but the four other pieces are different.

Before the game players choose their armies in a certain way, predefined by tournament rules. This can be done either randomly or secretly by both players. Each player has a choice of 4 armies: the Fabulous FIDEs, which are the standard chess pieces, the Colorbound Clobberers, the Nutty Knights, and the Remarkable Rookies.

All armies are designed to be equal in strength, but have significantly different properties. Kings and pawns move the same as in chess for all armies. Pawns can only promote to pieces of either army on the board at the start. Castling is done as in standard chess with the exception of the case when the rook replacement is colorbound, like in the Colorbound Clobberers army. In the latter case the king when castling long moves to b1 and the rook replacement to c1. This is so colorbound pieces don't change square color.

Many pieces in the following armies are combination of standard chess pieces and 4 fairy pieces: ferz, alfil, wazir and dabbaba (see their movement diagrams above). The game can be played with standard chess pieces and the following move diagrams use standard pieces as well (except queens).

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