3D Chess is played in a 4x4x4 cube. The rules of regular chess apply, subject to the following:

• Diagonal and knight motion take place in the horizontal plane or the two vertical planes defined by the horizontal plane's rows and columns;
• In addition to regular horizontal motion, pawns move up (down for black), capture up and to the left or right, and promote on the opponent's king row;
• No castling, en passant, or two-square pawn moves;
• Stalemate is a loss.