Tetriz

Tetriz (not to be confused with the other games by the same name) is a Tetris clone running either in a window on the Workbench or on its own screen. It is level-based, so clearing a certain number of lines resets the playfield and raises the difficulty. Higher levels are not only faster, but introduce blocking bricks and super-fast bricks. It is a well-featured implementation, with various bonuses for high drops, multiple lines, completing lines of one single colour or clearing the entire playfield.