Crosscut 2023

Crosscut is a two-player game played on a square board, size 10x10 or smaller, initially empty. (Board sizes larger than 10x10 may have deadlock issues.) Double sided discs, red on one side and blue on the other, are used. The two players, Red and Blue, take turns placing their own discs (discs showing their color) on the board, one disc per turn, starting with Red. If you have a placement available, you must make one. If you don’t have a placement available, your turn is skipped.

You win by forming a segment (horizontal or vertical contiguous sequence) of your discs of length two less than the size of the board. For example, on an 8x8 board, form a segment of length 6.

Placement and flippingYou can place a disc on any unoccupied square (subject to “perimeter” restrictions. See Perimeter section below.) “Flanked” will mean an enemy segment flanked between the newly placed friendly disc and another friendly disc. Flanking often results in flipping the flanked segment, but not always.

Consider what would happen if all flanked segments were flipped. If the longest friendly segment created would be longer than the longest enemy segment cut, then all flanked segments must be flipped. Otherwise no segments are flipped.

PerimeterThe perimeter is comprised of the edge and corner squares. You can temporarily place a disc in the perimeter only if it will cause an enemy segment to be flipped. (The perimeter disc is not considered to be part of a newly formed friendly segment in determining whether a placement would cause flipping.) Immediately after flipping, you must remove your perimeter disc. The perimeter is always unoccupied at the conclusion of a turn.