Although TaRocca employs hexagonal cards that look like cubes both to extend the traditional French card game, Tarot, and to enhance the layout and experience of using the deck for divination, most importantly, the game comes with instructions to play TaRocca Castle (タロッカ・キャッスル). As with a number of games from Rocca Spiele, the goal of the game is to empty your hand of cards. In this game, however, the minor and major arcana cards have distinct rules dictating how they must be played to build the titular castle. For a minor arcana example, cards of the same suit must be laid out to form a path, but cards of the same number must be laid out as if you were stacking the depicted cubes atop one another. Major arcana cards are placed as rooms at the ends of such paths. Additionally, each minor arcana suit has cards that provide special effects, such as forcing the next player to draw, or allowing you to forcibly give cards to another player.
As is traditional with Rocca Spiele games, the rules are fairly simple, with the focus being on producing an artistic 3D layout on the table.