So you’re going to need a deck of cards to play. (Well, really, two: one for the referee, and another for the players.) While the rules do provide a translation from Tarot to standard playing cards for the Minors in order to conduct task resolution, the most immersive experience obviously comes from using a full-sized actual Tarot deck to play. From character creation forward, players are asked to interact with the symbols present on the face of various cards; that’s complicated enough, but it bears mentioning that not all decks are the same.
There will necessarily be differing opinions on the importance of various visual cues in any given illustration on the face of a Tarot card: symbols are at once a code for shorthand communication and intensely personal. (Show two people a rose, and one may think of romance while the other recalls a funeral.) Thus, because House of Cards leaves players the actual task of assigning meaning to drawn cards, it’s quite possible to have a wide array of possible correspondences listed on a Bearer’s character sheet. As long as a player can make a reasonable case to the referee or other players to justify that correspondence, no other requirements need be met. One should, however, think on correspondences with an eye toward utility, as a too-narrow list hobbles your character’s magic, even as the referee should consider whether any of the noted correspondences are too broad and subject to abuse.
It also bears mentioning that, given the proliferation of Tarot decks on the market, it’s possible that one or more players may have their own set, and that the illustrations might deviate significantly from what might be considered the “baseline” sets, either the Rider-Waite deck or the Tarot de Marseille. While House of Cards is written with the assumption that these widely-available and familiar decks are the one most likely to appear at your table, they are not necessarily the only ones useful for or even endorsed by the game. During the writing process, I’ve drawn inspiration from the Paulina Tarot by Paulina Cassidy or Stephanie Pui-Mun Law’s Shadowscapes Tarot. Both incorporate novel twists on existing symbology from the Rider-Waite and other familiar decks, but with more evocative and detailed artwork that adds in cues of personal significance to the artists.
Be aware, also, that some decks alter their Major Arcana or their suits for different purposes. This may even mean that non-standard Archetypes appear in your Regalia. As the sage said, “Don’t panic.” As long as your group has a consensus of what to expect from these rogue cosmic forces, their appropriate correspondences, and their Greater Powers, feel free to explore the possibilities.