While this originally started as a list of alternative Trading Card Game deck builders, it quickly spun out into a list of games that use unique decks of cards. Some of these are deck builders, where you create a custom deck of cards from a pre-made selection to play against other people (Magic: The Gathering, for example, is a deck builder game), but most of these games simply ask that you draw from a deck of cards to play.
I just got carried away! Besides, this list also includes some of my favorite games that use unique decks to help graft a narrative, putting them solidly on the fence between a board game and a tabletop roleplaying game. Essentially, this is a list of kind of niche/under-the-radar games that use cards that I have enjoyed.