Xonix is an old action game. The purpose of the game is to move the player across the empty region (whereby it leaves his way in a brown color to show where it came along), and finally cut off a piece of unfilled region by moving him back to some filled region. If the player itself or the (unfilled yet) way will be hit by a flyer, a life will be lost again. Once the player's way reached another part of filled region, the way and all adjacent unfilled regions where there is no flyer in will be filled in turn. One level has com- pleted as soon as 75 % of the originally unfilled area have been filled this way. Every level, there will be one flyer more. Every second level, an additional player will be granted. Every fifth level, an additional eater will be fired off. The original xonix game has been seen somewhere on an old PC/XT clone. This is a reimplementation from scratch, done by Torsten Schönitz starting the project on a Macin- tosh. The X11 support has been written by Jörg Wunsch with the pleasant help by Alfredo Herrera Hernández.