Cos

Cos

Cos was an alien who acquired a gambling device that altered the laws of probability, so that those who won would experience good luck, and those who lost would experience bad luck.

Thanks to the good luck provided by the device, he garnered fame and fortune. However, by 2370, his luck had changed due to the device. His trade deals, alliances and every endeavour he made, failed.

In that year, he was being held in Deep Space 9's holding cells, when Odo placed Martus Mazur in the same cell as Cos. Soon after, Cos won the game, and immediately died, a contented man. (DS9: "Rivals")

Cos was played by Albert Henderson. The script refers to him at different times as "Cos" and "the Cos," making it unclear as to whether Cos is his name or his species.