Played on a 6X6 square board BS Chess uses similar pieces and movement patterns to chess. however the identity of a piece is only know to it's controller. This allows players make normally illegal moves. Like a knight's leap with a pawn or a pawn's capture with a knight. After each move the opposing player may or may not call BS (short for bluffing style) in that case the moving piece is revealed, and a penalty is given to moving player if they cheated or to the calling player if the move was legal. One other big change to chess is that the players pieces start in stacks along the back row of the board. This allows for a bit of meta gaming and reduces the number of choices each round even though a standard 16 man chess army is used.