In the game of Qix, the object is to claim portions of the play field by drawing Stix, or block areas, with the cursor marker. Enemies to avoid include: the Qix, a stick with trails that moves erratically about the unclaimed play field; the Sparx, small moving sparks that travel in opposite directions around the circumference of the unclaimed play field; and the Fuse, a Sparx that comes after the player's marker if it stops while drawing a Stix. There are two speeds with which to draw Stix, fast (green areas) and slow (red areas). Drawing slowly will garner more points, but leaves you vulnerable longer. Claiming 75% of the play field or more will clear the level and earn bonus points.
This Flash version of the classic game is very close to the original design and captures the essence of the game well. Press [space] to begin a game, arrow keys to move the marker, Z to draw fast Stix, and X to draw slow Stix.