Etana Jol was a Ktarian female who worked for her people as a military operative. She had the reputation for being one of the best card players in the Alpha and Beta Quadrants.
In 2368, she began a relationship with William Riker and introduced him to a game that took over a person's mind. (TNG episode: "The Game")
In 2370, Jol traveled to Deep Space 9 to take part in The First Annual Deep Space Nine Poker Tournament. As no arrest warrant had been issued for her detainment, Odo was unable to remove her from the space station as he initially wanted to. (DS9 novel: The Big Game)