oO

oO is an arcade game with minimal graphics. The player controls a small dot, moving along the rims of connected circles. By pressing a button the dot can be moved from the interior to the exterior and vice versa. If this is done at a point of contact between two circles, the dot moves to the other circle. Running into any obstacles destroys the player's dot and forces him to replay the level from the last checkpoint. Later levels add threats in the form of moving obstacles. The game keeps track of the number of deaths, and of runs with a record low death count.

The game also includes an "endless mode" where new circles keep appearing randomly in the player's path, while the player must quickly move from circle to circle before he is overtaken by an approaching wall. The objective in "endless mode" is simply to get as far as possible.