The Ktarian game was a single-player device worn over the ears and using a visual interface. The game displayed a grid pattern on which the player had to direct hovering disks into cone shaped objects over the course of multiple levels.
The first level consisted of only one disk and one cone, the second level had two cones and disks, and the third level had three of each. The game had at least 47 levels.
In 2368, Etana Jol introduced it to William T. Riker for the purpose of gaining control of Starfleet, while Riker was vacationing on Risa. Riker then unwittingly helped spread it aboard the USS Enterprise-D while en route to the Phoenix Cluster.
Wesley Crusher and Robin Lefler analyzed the game using a neurological behavior program in the engineering laboratory aboard the Enterprise and found that it rewarded a player's successful attempt by stimulating the pleasure center of the brain, creating a psychotropic addiction affecting higher reasoning and rendering that player completely submissive. It also activated the reticular formation and increased synaptic activity in the frontal lobe and prefrontal cortex.