I can't say that before Card Fighters I was very knowledgeable about card games (Magic, Pokemon, etc.), but I don't think that this hindered my enjoyment of the game any. It was a little overwhelming at first, but once I got the knack of it, it all started to make sense, and now, after 500 battles, I can say that I am the king of card fighter!!
SNK VS. CAPCOM presents you with 300 cards from all sorts of different games. And there is a laundry list of games they come from, too: Rival Schools United by Fate, Ghosts and Goblins, Strider, Street Fighter, Fatal Fury, World Heroes, Mega Man, Dark Stalkers, Samurai Shodown, Art of Fighting, Metal Slug, and many many many more. I don't think I even touched the tip of the iceberg. Each of the cards have different health, and some even have special abilities (some even KO other characters for you). Like I said earlier, it takes a couple of games to really get the feel for it (unless you are already a Pokemon fan), but once you get the hang of it, beating up your friends is extremely rewarding.
The graphics are simple, appropriate, while the music, as to be expected from the kind of game, is less that tolerable. It's a whole lot of fun, and a game I have spent more time playing that any other I can think of. I have logged in more than 100 hours, and I suspect I can do another 100. You will, mark my words, get addicted to getting all 300 cards (which seems easy at first, but really isn't). This is something of a novelty game, it really isn't anything serious, but where it fails to interest me in Pokemon, the characters in Card Clash make me want to keep playing it. And that's good clean fun!