Celtis is basically an othello game with a twist. The shape of the pieces, a 120° angled row of three "stones" with 2 blue stones and 1 green on a face and the reverse on the other, oblige a player to always play the opponent color. The first player to make a 7-row wins.

It's an all plastic game, the depressions on the board match the shape of the stones, and the stones "slip" in the rows neatly. The board is also a box for the stones.

The author of the game is an industrial designer.