Two players (Blue vs Red) face off in a struggle to line up four of their own chips vertically, horizontally or diagonally, before the other beats them to it. Click a grey circle atop a slot to drop a chip. The chip will fall to the bottommost unreserved location in that column. Turns alternate until one player connects four in a row.
- A special thanks goes to Lucifer Jr for supplying the icons used for red and blue chips.