Linkaway

Linkaway is a connection game for two players: Black and White. It is played on the intersections (points) of an initially empty square grid (board). The top and bottom edges of the board are colored black; the left and right edges are colored white.

Black plays first, then turns alternate. On your turn, place a stone of your color on an empty point without forming any of these patterns:

 Empty diagonal: 2×2 area with two diagonally adjacent stones of the same color and two empty points.
 Approach: 2×2, 2×3 or 2×4 area with no stones other than one black stone and one white stone at the two opposite ends of one of the longer sides.

Passing is not allowed, but, if you have no legal moves available, your turn is skipped.

You win if there is a chain of orthogonally interconnected stones of your color touching the two opposite board edges of your color.

To make the game fair, White will have the option, on their first turn only, to swap sides with Black instead of making a regular move.

—description from the designer