Pentominoes is our tribute to Tetris Â®, a famous arcade game created years ago in the Soviet Union by Alexey Pajitnov. Pentominoes began in Roman times, a game with odd shaped pieces that come together to form a square or rectangle. Pentominoes will look familiar to anyone who’s played Tetris Â®. The pieces are all the shapes one can make by combining five squares. Tetris Â® pieces, however, are constructed of four squares instead of five.There are a total of 12 pieces, adding up to a total of 60 squares. You can arrange these pieces in four different rectangles. There are many solutions for most, but only two solutions for a 20 x 3 rectangle. You can flip and rotate the pieces as much as you want.