A very difficult positional puzzle, this is an enhanced version based on Paul Bunn's Atari BASIC game from 1983's type-in listing book "Games For Your Atari Computer".

Click tiles to place the computer's selected color in them, beginning with the four corners of the diamond grid. From there, all tiles must be placed horizontally or vertically next to an existing colored tile, but they cannot be placed neighboring the same color horizontally, vertically or diagonally.

When out of moves, click the X to reset the board. The game also supports keyboard input just like the Atari 8-bit original.