In Citadels, players take on new roles each round to represent characters they hire in order to help them acquire gold and erect buildings. The game ends at the close of a round in which a player erects their eighth building. Players then tally their points, and the player with the highest score wins.

The 2016 edition of Citadels includes twenty-seven characters eight from the original Citadels, ten from the Dark City expansion, and nine new ones along with thirty unique building districts, and the rulebook includes six preset lists of characters and districts beyond the starter list, each crafted to encourage a different style and intensity of gameplay.