Breakthrough is a game played on an 8x8 rectangular board.  White pieces on the bottom two rows of the board and and black pieces on the top two rows of the board.  Pieces can move forward one step or diagonally one step.  White pieces move up the board, and black pieces move down the board.  Only one piece permitted on a square at a time.  Opponent's pieces can be captured diagonally only.  The winner is the first player to advance one of its pieces to the opposite end of the board.