Amoeba (1975)

The board consists of a 7x7 array of plastic squares, each of which has an arc cutting two diagonally opposite corners.

The rest of the equipment is a deck of 52 cards showing various closed amoeba-like curves that can be made with the arcs - players get 3 of these to start and are trying to create the curves shown on their cards.

On a turn a player gets to rotate any piece except the one last rotated, and if a needed shape is made, the player gets the points shown on the card, a new card, and another turn. The first player to reach 50 points wins.

Amoeba has been published as 'Tantalus' in the Ravensburger Casino Series.

Another game which uses this very unusual tile to form its board is Truchet