Geeks had already been playing Magic: The Gathering from Wizards of the Coast for a while when, in 1994, Decipher, Inc. launched Star Trek: The Next Generation - Customizable Card Game. The premise of a customizable card game is that you collect these cards (just like baseball cards), but you play a game with them. It's like a board game, where you create the board and supply all the pieces with cards. Because it was initially based upon Star Trek: The Next Generation (Decipher's rights later expanded to include the entire Trek franchise), there was no shortage of secondary and even tertiary material to mine for content.
It was a fun game, though Decipher had at least two things going against them from the outset. Firstly, because the game was designed with only The Next Generation in mind, as they expanded to include other spin-off series and movies, the new elements were either underwhelming and superfluous, or they were introduced in some kind of convoluted manner meant to introduce new gameplay but was rarely attractive to players.
The other problem was that this was in the dawn of the Internet going mainstream. Collectors and fans were still largely reliant upon local specialty shops for their supply. Meeting other players was difficult unless you knew another Trekkie/Trekker. In the Louisville area, we had several retailers--the best, in my opinion, was Book & Music Exchange on Preston Highway. They had a steady supply of single cards for sale and even organized a tournament over the summer of 1996. It came down to a friend and myself, and rather than play one another, we simply flipped a POG slammer of Judge Lance Ito for the win.
Here are some scans of various promotional materials. Feel free to comment below if you've got any memories of this game!