Crosswire 2026

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

A crosscut is a 2×2 area with two diagonally adjacent black stones and two diagonally adjacent white stones. You own a crosscut if you occupy the majority of the total number of points on the two diagonals of the board that cross at the center of the crosscut. Two stones of your color are connected if they are orthogonally adjacent or they belong to the same crosscut and you own that crosscut.

Black plays first, then turns alternate. On your turn, place a stone of your color on an empty point. You win if there is a chain of 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.

NotesCrosswire is based on the observation that, on an odd-sized square grid, any two crossing diagonals that do not share an intersection of the grid always cross an odd total number of intersections of the grid. This guarentees that all crosscuts will eventually be owned by one player or the other.

—description from the designer