You want a card based RPG with a narrativist creative agenda and a horror theme. I would check out the free
Predator Echos. It's a Dogs in the Vineyard hack by Levi Kornelsen that is a monster hunter hurror game using cards instead of dice. Dogs is potentially my favorite narrativist game, and while I haven't played Predator Echos, it seems pretty fun. It has a few tweaks to the original Dogs that seem like they would run well. It also uses cards in a creative way, without a lot of complications to make it unwieldy. It would be a simple matter to add a little bit to the game and use a Tarot deck instead of the standard playing card deck. The game is not completely finished, and it requires at least familiarity with the original Dogs, but to me that sounds like an excuse to buy Dogs anyway if you don't have it. Oh, and it is FREE.
Another one that would be fun would be
Geiger Counter. Geiger Counter is a slick free game that is a hack of a hack of Dogs in the Vineyard that turns out to be nothing like Dogs. It is designed to be a no-prep, rules-light, one-shot GM-less narrativist game. You could add a GM and a little prep if you wanted, but it is unnecessary. The simple mechanic would easily allow the use of cards (flip cards, choose top 2, compare to the top 2 of the opposition) and the GM-less nature would allow the use of the major arcana in interesting foreshadowing/prescription ways with very little modification from the original. Did I mention it was FREE?
Another favorite of mine is
InSpectres. This is pretty much Ghost Busters the RPG, done in a rules light, very low prep, narrativist game. The mechanic is simple enough that cards could be used with minimal easy hacking, and like previous examples, the rules are light enough that you can add a lot using the major arcana. InSpectres is one of the most fun games around, and having an excuse to buy it ($!0 pdf) might be good. There are also some free supplements to make it darker (a la Cthulhu mythos). InSpectres is not free, but it is relatively CHEAP, and well worth it.
I could easily come up with more, but those would probably be my top choices, and if you want more, I'll brainstorm with you. Check those out first though.