An I-Tetrimino (also sometimes called a Line Piece) is a tetromino that is four blocks in a straight line. It has the dimensions of one Mino by four Minoes. If rotated either way, the I-Tetrimino will change orientations from vertical (1x4) to horizontal (4x1), and vice versa. The I-Tetrimino is a unique piece as it is the only tetromino that can cause a Tetris.