@nprofile1q... why not just have deck.txt be a file containing card references styled almost as filenames, one per line, like:
magic/onecard
uno/anothercard
yugioh/athirdcard
standard/4h
etc.?
rendering the image corresponding to a card is the job of the software, and you could download texture packs for the cards. so one guy might use an ornate standard deck styled in the old italian way, while another guy might use a muted, simple german style. you could even define variants like foil, gold, shiny, etc. for stuff like *mon cards, the only limit being what your texture packs support...
the midi principle, in essence.