Onexeno is a game similar to dominoes with a bit of Gipf thrown in.

There are 70 tiles, 1 for each possible combination of dark and light shadings around the periphery of a 3X3 matrix, e.g.

You take turns playing and picking tiles, or just picking if you can’t play. The table space is an artificial 5×5 board, defined as the tiles are placed. You must match tiles when you place. Whenever you form five tiles in a row, you take the tiles.

The game ends when no one can play any more. Your score is the number of tiles you’ve taken minus the number left in your hand.

Only less cool people will realize Onexeno is a palindrome spelled out on the back of the tiles.