The Black Path Game (also known by various other names, such as Brick) is a two-player board game described and analysed in Winning Ways for your Mathematical Plays. It was invented by Larry Black in 1960.
It has also been reported that a game known as "Black" or "Black's Game" was invented in 1960 by William L. Black. This "William L. Black" (possibly known as "Larry") was at that time an undergraduate at the Massachusetts Institute of Technology, investigating Hex and Bridg-It, two games based on the challenge to create a connected "chain" of counters that link opposite sides of a game board. The creative outcome of Black's research was a new topological game that his friends (perhaps unimaginatively) called Black. The game was introduced to the public by Martin Gardner in his October 1963 "Mathematical Games column" in Scientific American.
Rules
The Black Path Game is played on a board ruled into squares. One edge on the boundary of the board is designated to be the start of the path. After the first move, the players extend the path away from the starting edge by alternately filling the adjacent square at the end of the current path with one of three configurations shown below.
Any square that is not empty is filled with one of the following configurations that contains two paths linking two sides:
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Image:Square (02) 12-34.svg|T1 tile, with paths connecting adjacent sides (top and left, and bottom and right)
Image:Square (02) 14-23.svg|T2 tile, with paths connecting adjacent sides (top and right, and bottom and left)
Image:Square (20) 13-24.svg|T3 tile, with paths connecting opposite sides (top and bottom, and left and right)
</gallery>
These tiles are the three ways to join the sides of the square in pairs. The first two are
the tiles of the Truchet tiling.
The path may return to a previously filled square and follow the yet-unused segment on that square. The player who first causes the path to run back into the edge of the board loses the game.