One player is red/orange/yellow and the other is green/blue/violet. The winner of the game who places down more of his or her tokens onto the playing board than the opposing player. Each color which is placed on the playing board must always touch an adjoining color in the correct sequence of the spectrum (red may only touch orange, green may only touch yellow and blue, and so on). The game starts with each player playing their six extreme tiles (red and violet) anywhere on the board, not touching each other. It is from this start the remaining tiles are played. There is an alternate set of simpler rules for younger children. - BoardGameGeek